The purpose of this blog is the creation of an open, international, independent and free forum, where every UFO-researcher can publish the results of his/her research. The languagues, used for this blog, are Dutch, English and French.You can find the articles of a collegue by selecting his category. Each author stays resposable for the continue of his articles. As blogmaster I have the right to refuse an addition or an article, when it attacks other collegues or UFO-groupes.
Druk op onderstaande knop om te reageren in mijn forum
Zoeken in blog
Deze blog is opgedragen aan mijn overleden echtgenote Lucienne.
In 2012 verloor ze haar moedige strijd tegen kanker!
In 2011 startte ik deze blog, omdat ik niet mocht stoppen met mijn UFO-onderzoek.
BEDANKT!!!
Een interessant adres?
UFO'S of UAP'S, ASTRONOMIE, RUIMTEVAART, ARCHEOLOGIE, OUDHEIDKUNDE, SF-SNUFJES EN ANDERE ESOTERISCHE WETENSCHAPPEN - DE ALLERLAATSTE NIEUWTJES
UFO's of UAP'S in België en de rest van de wereld Ontdek de Fascinerende Wereld van UFO's en UAP's: Jouw Bron voor Onthullende Informatie!
Ben jij ook gefascineerd door het onbekende? Wil je meer weten over UFO's en UAP's, niet alleen in België, maar over de hele wereld? Dan ben je op de juiste plek!
België: Het Kloppend Hart van UFO-onderzoek
In België is BUFON (Belgisch UFO-Netwerk) dé autoriteit op het gebied van UFO-onderzoek. Voor betrouwbare en objectieve informatie over deze intrigerende fenomenen, bezoek je zeker onze Facebook-pagina en deze blog. Maar dat is nog niet alles! Ontdek ook het Belgisch UFO-meldpunt en Caelestia, twee organisaties die diepgaand onderzoek verrichten, al zijn ze soms kritisch of sceptisch.
Nederland: Een Schat aan Informatie
Voor onze Nederlandse buren is er de schitterende website www.ufowijzer.nl, beheerd door Paul Harmans. Deze site biedt een schat aan informatie en artikelen die je niet wilt missen!
Internationaal: MUFON - De Wereldwijde Autoriteit
Neem ook een kijkje bij MUFON (Mutual UFO Network Inc.), een gerenommeerde Amerikaanse UFO-vereniging met afdelingen in de VS en wereldwijd. MUFON is toegewijd aan de wetenschappelijke en analytische studie van het UFO-fenomeen, en hun maandelijkse tijdschrift, The MUFON UFO-Journal, is een must-read voor elke UFO-enthousiasteling. Bezoek hun website op www.mufon.com voor meer informatie.
Samenwerking en Toekomstvisie
Sinds 1 februari 2020 is Pieter niet alleen ex-president van BUFON, maar ook de voormalige nationale directeur van MUFON in Vlaanderen en Nederland. Dit creëert een sterke samenwerking met de Franse MUFON Reseau MUFON/EUROP, wat ons in staat stelt om nog meer waardevolle inzichten te delen.
Let op: Nepprofielen en Nieuwe Groeperingen
Pas op voor een nieuwe groepering die zich ook BUFON noemt, maar geen enkele connectie heeft met onze gevestigde organisatie. Hoewel zij de naam geregistreerd hebben, kunnen ze het rijke verleden en de expertise van onze groep niet evenaren. We wensen hen veel succes, maar we blijven de autoriteit in UFO-onderzoek!
Blijf Op De Hoogte!
Wil jij de laatste nieuwtjes over UFO's, ruimtevaart, archeologie, en meer? Volg ons dan en duik samen met ons in de fascinerende wereld van het onbekende! Sluit je aan bij de gemeenschap van nieuwsgierige geesten die net als jij verlangen naar antwoorden en avonturen in de sterren!
Heb je vragen of wil je meer weten? Aarzel dan niet om contact met ons op te nemen! Samen ontrafelen we het mysterie van de lucht en daarbuiten.
19-06-2022
President Eisenhower’s Extraterrestrial Legacy: Interview with Laura Eisenhower
President Eisenhower’s Extraterrestrial Legacy: Interview with Laura Eisenhower
In this Exopolitics Today interview, Laura Eisenhower, the great granddaughter of President ‘Ike’ Eisenhower, discusses how she got involved in UFO and esoteric related topics. She discusses her family background and the meetings Ike had with different extraterrestrial groups, especially with Valiant Thor.
Laura explains how Ike was betrayed by the MJ-12 Group which made agreements with a negative extraterrestrial group without his approval that led to him being on the verge of authorizing the US Army to invade Area 51 to take control of classified extraterrestrial projects. She also explains an attempt by the Deep State/Cabal to recruit her to go to Mars 2006, where she would have been prevented from taking part in the great awakening happening right now on Earth. Laura shares her many insights into metaphysics, astrology, key figures in her spiritual work, and humanity’s great awakening.
A Rare Repeating Fast Radio Burst Gives Astronomers a Chance to Study These Mysterious Objects
A Rare Repeating Fast Radio Burst Gives Astronomers a Chance to Study These Mysterious Objects
Fast Radio Bursts (FRBs) are among the most mysterious astronomical phenomena facing astronomers today. While hundreds of bursts have been detected since the first-ever recorded detection of an FRB in 2007 – the Lorimer Burst – astronomers are still unsure what causes them. Even more mysterious, some have occasionally been found to be repeating in nature, which has fueled speculation that they may not be natural in origin (i.e., possible alien transmissions?). Astronomers are naturally very excited whenever a repeating FRB is found, as it gives them the chance to examine them closer.
In a recent survey, an international team of scientists used three major telescopes worldwide to study a repeating FRB (known as FRB 190520) that was first observed in 2019. According to their observations, this particular FRB is not just a repeating source from a compact object but a persistent one that emits low-level bursts of radio waves between larger ones. These findings raise new questions about the nature of these mysterious objects and how they can be used as tools to probe the space between stars and galaxies.
FRBs are short-lived, intense blasts of radio energy that typically last for a few milliseconds and are never heard from again. The first FRB was detected in 2007 by Duncan Lorimer, an astronomer at West Virginia University (hence the name “Lorimer Burst “) and several hundred have been detected ever since. Whereas most FRBs detected have been one-off events, a few have been repeating in nature and have even been traced back to their sources.
Because of these efforts, astronomers have found a strong link between repeating FRBs and magnetars, a highly-magnetized type of neutron star. Combined with global coordination efforts, astronomers have gathered a huge amount of data on these transient objects to the point that their transient nature is no longer impeding research into them.
Two of a Kind
FRB 190520 was first noticed by scientists at China’s FAST array on May 20th, 2019, after sifting through data obtained in November of that year. Follow-up observations conducted with FAST immediately afterward showed that this source was repeating in nature. In 2020, observations with the Karl G. Jansky Very Large Array (VLA) pinpoint the object’s location, while visible-light observations with the Subaru Telescope in Hawaii showed that this placed it in the outskirts of a dwarf galaxy nearly 3 billion light-years from Earth.
The data obtained with the VLA also determined that the object constantly emits weaker radio waves between bursts. These observations provided the first information about the environment and distance of an FRB, which constituted a major breakthrough in the study of these objects. However, the combination of repeating bursts and persistent radio emissions from a compact region meant that this discovery was only the second of its kind. As Caltech astronomer (and study co-author) Casey Law explained, the only other object of this kind was FRB 121102, which was spotted in 2016.
“These characteristics make this one look a lot like the very first FRB whose position was determined — also by the VLA — back in 2016,” she said. “Now we have two like this, and that brings up some important questions.” The differences between these two sources and all others detected to date strengthen the possibility that there may be two distinct types of FRBs, something astronomers have long suspected.
Possible Explanations
The team proposed that these results could indicate one of two things. First, there’s the possibility that there may be different mechanisms producing the two types of FRBs observed (single events and repeating) or that the objects producing them may be at different stages in their evolution. As noted, the leading candidates for FRBs are thought to be neutron stars with ultra-strong magnetic fields – called magnetars. But after examining FRB 190520, they came to the tentative conclusion that it may be a “newborn” neutron star.
Essentially, this means that the neutron star is still surrounded by dense clouds of dust and gas, which are the remains of the star’s outer layers that were ejected when it went supernova. The presence of this material, they claim, would explain the effect the source’s radio waves had on the surrounding environment. Like pulsars, FRBs affect the dust and gas that lies between star systems and galaxies, which astronomers can study to learn more about the material. For instance, when radio waves pass through space containing free electrons, higher-frequency waves travel faster than low-frequency waves.
The region of FRB 190520 with the VLA image of the Fast Radio Burst alternating between the object bursting and not bursting. Credit: Niu, et al.; Bill Saxton, NRAO/AUI/NSF; CFHT
This effect is known as “dispersion” and can be measured to determine the density of electrons in interstellar or intergalactic space. In instances where the density of electrons in the intervening space is known, FRBs can also be used to determine the distance between a source and Earth. When the team attempted to make distance measurements based on the dispersion effect FRB 190520 had on the surrounding gas and dust, the results indicated a distance of roughly 8 to 9.5 billion light-years. However, independent measurements based on the source’s Doppler shift produced an estimate of almost 3 billion light-years.
This explanation has multiple implications for the study of FRBs. For one, it demonstrates that repeating bursts could be characteristic of younger neutron stars and that these FRBs dwindle with age as the gas and dust clouds surrounding them dissipate. Second, it raises questions about how useful FRBs could be in determining the distances between celestial objects and the density of the space between them. Said Aggarwal:
“This means that there is a lot of material near the FRB that would confuse any attempt to use it to measure the gas between galaxies. If that’s the case with others, then we can’t count on using FRBs as cosmic yardsticks.”
While it is clear that many questions remain about the sources and mechanisms of Fast Radio Bursts, the progress being made in this field is astounding. Only fifteen years ago, astronomers had observed one for the first time and didn’t realize they came in two distinct forms. Today, FRBs are being detected and tracked by the hundreds, and astronomers are getting closer to determining the key characteristics of both types. In this sense, the field of FRB research is right up there with research into Gravitational Waves (GW), infrared astronomy, exoplanet studies, astrobiology, and others that are progressing by leaps and bounds!
Crashed Extraterrestrial Vehicle Retrieval Manual in Governmental The Majestic Documents: Origins and Impact Today
Crashed Extraterrestrial Vehicle Retrieval Manual in Governmental The Majestic Documents: Origins and Impact Today
Dr. Robert Wood and Ryan Wood have been investigating leaked Majestic Documents since 1994 when the former was given a leaked copy of an apparent official document used by military personnel for retrieval operations of crashed extraterrestrial spacecraft. Dr. Wood had only a year earlier retired from a 43 year career with McDonnell Douglas/Douglas Aircraft company as an aerospace scientist on projects such as the Project Nike anti-missile defense system. He was helped in his document investigation by his son Ryan – who currently runs an alternative energy company. After a rigorous forensic investigation they concluded the SOM document was authentic. Over the subsequent years the Woods team have investigated many official documents that have security classifications such as MAJIC, MJ-12, MAJESTIC, JEHOVAH, and UMBRA.
Dr. Robert Wood and Ryan Wood have been investigating leaked Majestic Documents since 1994 when the former was given a leaked copy of an apparent official document used by military personnel for retrieval operations of crashed extraterrestrial spacecraft. Dr. Wood had only a year earlier retired from a 43 year career with McDonnell Douglas/Douglas Aircraft company as an aerospace scientist on projects such as the Project Nike anti-missile defense system. He was helped in his document investigation by his son Ryan – who currently runs an alternative energy company. After a rigorous forensic investigation they concluded the SOM document was authentic.
Over the subsequent years the Woods team have investigated many official documents that have security classifications such as MAJIC, MJ-12, MAJESTIC, JEHOVAH, and UMBRA. These have been compiled on a website created by Ryan called MajesticDocuments.com. He cited many Majestic Documents in his groundbreaking 2005 book, Majic Eyes Only, where he examined 74 crash retrieval cases.
In their first joint interview with Dr. Michael Salla, the Woods discuss how they got involved in researching the Majestic Documents, the contents of key documents for understanding UFO history. Especially significant was their research into the Burned Memo document which they concluded is linked to the assassination of President John F. Kennedy for his efforts to declassify the UFO topic.
These have been compiled on a website created by Ryan called MajesticDocuments.com. He cited many Majestic Documents in his groundbreaking 2005 book, Majic Eyes Only, where he examined 74 crash retrieval cases. In their first joint interview with Dr. Michael Salla, the Woods discuss how they got involved in researching the Majestic Documents, the contents of key documents for understanding UFO history. Especially significant was their research into the Burned Memo document which they concluded is linked to the assassination of President John F. Kennedy for his efforts to declassify the UFO topic. More information about Dr. Robert Wood and Ryan Wood is available at MajesticDocuments.com
Strange Disney Movie Proves In 1959 They Were Able To Move a Hurricane!
Strange Disney Movie Proves In 1959 They Were Able To Move a Hurricane!
In 1959 They Were Able To Move a Hurricane! A Walt Disney Presentation? BEOFRE we look to ‘Space Force’ lets analyze our past. Can you handle the truth? Examine the Past, Before we move Forward. #SpaceForce #Nasa #Dorian2019
The Banned Disney UFO Documentary: Alien Encounters From New Tomorrowland
The Banned Disney UFO Documentary: Alien Encounters From New Tomorrowland
“Alien Encounters From New Tomorrowland” BANNED DISNEY UFO DOCUMENTARY In March of 1995, without warning, Disney aired a family special. the documentary was so controversial that it was pulled from the airwaves and banned from ever being shown again. Robert Urich, the legendary Jim Street in S.W.A.T. (1975), is the host of this voyage around the UFO’s and its mystery.
From New Tomorrowland, in Disneyland, Urich talks about UFO, contacts, evidence of it arrives, abductions, military documents, and other things that surround this controversial thematic. From the 30′s years ahead, the UFOs always have been there very close to us, every day, every time. Exist the aliens?,in truth, they come to planet Earth? Could it be a fiction created by the military?
And the last and most important question: if they exist, would they will be our friends…or our enemies? Written by Chockys
NASA Lies Again Announcing Formation of Committee To Investigate UFOs! UFO Sighting News.
NASA Lies Again Announcing Formation of Committee To Investigate UFOs! UFO Sighting News.
NASA was created on July 29, 1958 in order to hide the existence of aliens from the public. Yeah its different than you thought, but its 100% true.
This week NASA announced that its assembling a team to research the possibility of UFOs existing. Thats like asking a lion to kindly watch over and protect your baby lamb for a few days while you are away. The truth is NASA will create the UFO committee the same way and purpose that NASA itself was created for...to hide the truth about the existence of aliens from the public, but all the while drop feeding worthless scientific facts to the public which is meant to appease the curiosity of the public.
I can give you a list of ten astronauts who each say they saw a UFO and give you word for word what they say about it. So if you want to go and believe a fake committee that is being created to discredit and disinform the public about the truth, go right ahead. However for over 64 years NASA has lived up to its public nickname, Never A Straight Answer.
There is one and only one way for the truth to come out. For the public to hunt it down, grab it, and drag it out into the public square for all to see (Social Media). Only the public can reveal the truth, only the public has the trust of other people. The other countries around the world lost trust in America after the fake moon landings to make the USA appear as a world power...which by the way, are listed as fakes in lots of student history books worldwide.
Hey, I found this huge wall that crosses the right side of the south pole on Mars. The wall measures 250km long and about 45km tall. The ruler to get those measurements are on the bottom of the photo, placed there by NASA so you know its accurate. There are also a lot of other structures, a city, some 30km alien ships in craters, some square bases in craters and more. So many things in this photo, but understand, it was colorful, but I changed the photo into black and white so that I could see the structures better. Otherwise, it would be impossible to see.
In a ten minute video, I revealed more than NASA did in the last 50 years! Do you still believe NASA offering to help research UFOs is a true offer of help from them? Because if you do, then I got a 30km aliens ship on Mars I want to sell you.
0
1
2
3
4
5
- Gemiddelde waardering: 0/5 - (0 Stemmen) Categorie:Ruins, strange artifacts on other planets, moons, ed ( Fr, EN, NL )
Space Relic Uncovered at UFO Crash Site
Space Relic Uncovered at UFO Crash Site
Ancient Astronaut Theorists travel to central New Mexico to examine a UFO crash site related to Roswell, in this clip from Season 15, “The Relics of Roswell.”
Civilizations Don’t Even Need Space Ships to Migrate From Star System to Star System
Civilizations Don’t Even Need Space Ships to Migrate From Star System to Star System
In about 5 billion years, the Sun will leave themain sequence and become a red giant. It’ll expand and transform into a glowering, malevolent ball and consume and destroy Mercury, Venus, Earth, and probably Mars. Can humanity survive the Sun’s red giant phase? Extraterrestrial Civilizations (ETCs) may have already faced this existential threat.
Could they have survived it by migrating to another star system without the use of spaceships?
Universe Today readers are well-versed in the difficulties of interstellar travel. Our nearest neighbouring solar system is the Alpha Centauri system. If humanity had to flee an existential threat in our Solar System, and if we could identify a planetary home in Alpha Centauri, it would still take us over four years to get there—if we could travel at the speed of light!
It still takes us five years to get an orbiter to Jupiter at our technological stage. There’s lots of talk about generation starships, where humans could live for generations while en route to a distant habitable planet. Those ships don’t need to reach anywhere near the speed of light; instead, entire generations of humans would live and die on a journey to another star that takes hundreds or thousands of years. It’s fun to think about but pure fantasy at this point.
This is an image of the Nauvoo generation ship from “The Expanse.” Generation ships are the stuff of science fiction, for now. Image Credit: Legendary Television Distribution.
Is there another way we, or other civilizations, could escape our doomed homes?
The author of a new research article in the International Journal of Astrobiology says that ETCs may not need starships to escape existential threats and travel to another star system. They could instead use free-floating planets, also known as rogue planets. The article is “Migrating extraterrestrial civilizations and interstellar colonization: implications for SETI and SETA.” The author is Irina Romanovskaya. Romanovskaya is a Professor of Physics and Astronomy at Houston Community College.
“I propose that extraterrestrial civilizations may use free-floating planets as interstellar transportation to reach, explore and colonize planetary systems,” Romanovskaya writes. And when it comes to the search for other civilizations, these efforts could leave technosignatures and artifacts. “I propose possible technosignatures and artifacts that may be produced by extraterrestrial civilizations using free-floating planets for interstellar migration and interstellar colonization, as well as strategies for the search for their technosignatures and artifacts,” she said.
It’s possible that rogue planets, either in the Milky Way or some of the other hundreds of billions of galaxies, carry their own life with them in subsurface oceans kept warm by radiogenic decay. Then if they meet a star and become gravitationally bound, that life has effectively used a rogue planet to transport itself, hopefully, to somewhere more hospitable. So why couldn’t a civilization mimic that?
We think of free-floating planets as dark, cold, and inhospitable. And they are unless they have warm subsurface oceans. But they also offer some advantages. “Free-floating planets can provide constant surface gravity, large amounts of space and resources,” Romanovskaya writes. “Free-floating planets with surface and subsurface oceans can provide water as a consumable resource and for protection from space radiation.”
An advanced civilization could also engineer the planet for an even greater advantage by steering it and developing energy sources. Romanovskaya suggests that if we’re on the verge of using controlled fusion, then advanced civilizations might already be using it, which could change a frigid rogue planet into something that could support life.
The author outlines four scenarios where ETCs could take advantage of rogue planets.
The first scenario involves a rogue planet that happens to pass by the homeworld of an ETC. How often that might occur is tied to the number of rogue planets in general. So far, we don’t know how many there are, but there are certainly some. In 2021, a team of researchers announced the discovery of between 70 and 170 rogue planets, each the size of Jupiter, in one region of the Milky Way. And in 2020, one study suggested there could be as many as 50 billion of them in our galaxy.
Where do they all come from? Most are likely ejected from their solar systems due to gravitational events, but some may form via accretion as stars do.
Another source of rogue planets is our Solar System’s Oort Cloud. If other systems also have a cloud of objects like this, they can be an abundant source of rogue planets ejected by stellar activity. Romanovskaya writes: “Stars with 1–7 times solar mass undergoing the post-main-sequence evolution, as well as a supernova from a 7–20 times solar mass progenitor, can eject Oort-cloud objects from their systems so that such objects become unbound from their host stars.”
But how often can an ETC, or our civilization, expect a rogue planet to come close enough to hitchhike on? A 2015 study showed that the binary star W0720 (Scholz’s star) passed through our Solar System’s Oort Cloud about 70,000 years ago. While that was a star and not a planet, it shows that objects pass relatively close by. If the studies that predict billions of free-floating planets are correct, then some of them likely passed close by, or right through, the Oort Cloud long before we had the means to detect them.
The Oort Cloud is a long way away, but a sufficiently advanced civilization could have the capability to see a rogue planet approaching and go out and meet it.µ
Zooming out; the inner solar system (upper left), the outer solar system (upper right), the orbit of Sedna (lower right) and the inner edge of the Oort cloud (lower left). Image credit: NASA
The second scenario involves using technology to steer a rogue planet closer to a civilization’s home. With sufficient technology, they could choose an object from their own Oort Cloud—assuming they have one—and use a propulsion system to direct it towards a safe orbit near their planet. With sufficient lead time, they could adapt the object to their needs, for example, by building underground shelters and other infrastructure. Maybe, with adequate technology, they could alter or create an atmosphere.
The third scenario is similar to the second one. It also involves an object from the civilization’s outer Solar System. Romanovskaya uses the dwarf planet Sedna in our Solar System as an example. Sedna has a highly eccentric orbit that takes it from 76 AUs from the Sun to 937 AU in about 11,000 years. With sufficient technology and lead time, an object like Sedna could be turned into an escape ship. The author notes that “Civilizations capable of doing so would be advanced civilizations that already have their planetary systems explored to the distances of at least 60 AU from their host stars.”
Artist’s conception of Sedna, a dwarf planet in the solar system that only gets within 76 astronomical units (Earth-sun distances) of our Sun. Credit: NASA/JPL-Caltech
There are lots of potential problems. Bringing a dwarf planet from the distant reaches of the Solar System into the inner Solar System could disrupt the orbits of other planets, leading to all sorts of hazards. But the dangers are mitigated if a civilization around a post-main sequence star has already migrated outward with the changing habitable zone. Romanovskaya discusses the energy needed and the timing required in more detail in her article.
The fourth scenario also involves objects like Sedna. When a star leaves the main sequence and expands, there’s a critical distance where objects will be ejected from the system rather than remain gravitationally bound to the dying star. If an ETC could accurately determine when these objects would be ejected as rogue planets, they could prepare it beforehand and ride it out of the dying solar system. That could be extraordinarily perilous, as periods of violent mass loss from the star creates an enormous hazard.
Three rings of ejected gas sail away from an aging star named V Hydrae, seen in this false-colour radio image from the Atacama Large Millimeter/submillimeter Array in Chile. Image Credit: ALMA
In all of these scenarios, the rogue planet or other body isn’t a permanent home; it’s a lifeboat. “For all the above scenarios, free-floating planets may not serve as a permanent means of escape from existential threats,” the author explains. “Because of the waning heat production in their interior, such planets eventually fail to sustain oceans of liquid water (if such oceans exist).”
Free-floating planets are also isolated and have fewer resources than planets in a solar system. There are no asteroids to mine, for example, and no free solar energy. There are no seasons and no night and day. There are no plants, animals, or even bacteria. They’re simply a means to an end. “Therefore, instead of making free-floating planets their permanent homes, extraterrestrial civilizations would use the free-floating planets as interstellar transportation to reach and colonize other planetary systems,” writes Romanovskaya.
In her article, Professor Romanovskaya speculates where this could lead. She envisions a civilization that does this more than once, not to escape a dying star but to spread throughout a galaxy and colonize it. “In this way, the parent-civilization may create unique and autonomous daughter-civilizations inhabiting different planets, moons or regions of space.”
“A civilization of Cosmic Hitchhikers would act as a ‘parent-civilization’ spreading the seeds of ‘daughter-civilizations’ in the form of its colonies in planetary systems,” she writes. “This applies to both biological and post-biological species.”
Artist’s rendering of an Earth-sized rogue planet approaching a star. Credit: Christine Pulliam (CfA)
Humanity is only in the early stages of protecting ourselves from catastrophic asteroid impacts, and we can’t yet manage our planet’s climate with any degree of stability. So thinking about using rogue planets to keep humanity alive seems pretty far-fetched. But Romanovskaya’s research isn’t about us; it’s about detecting other civilizations.
All of this activity could create technosignatures and artifacts that signified the presence of an ETC. The research article outlines what they might be and how we could detect them. Rogue planets used as lifeboats could create technosignatures like electromagnetic emissions or other phenomena.
An ETC could use solar sails to control a rogue planet or use them on a spaceship launched from a rogue planet once they have reached their destination. In either case, solar sails produce a technosignature: cyclotron radiation. Maneuvering either a spacecraft or a rogue planet with solar sails would produce “… cyclotron radiation caused by the interaction of the interstellar medium with the magnetic sail.”
Infrared emissions could be another technosignature emitted as waste heat by an ETC on a rogue planet. An excessive amount of infrared or unnatural changes in the amount of infrared could be detected as a technosignature. Infrared could be emitted unevenly across the planet’s surface, indicating underlying engineering or technology. An unusual mix of different wavelengths of electromagnetic energy could also be a technosignature.
The atmosphere itself, if one existed, could also hold technosignatures. Depending on what was observed, it could contain evidence of terraforming.
For now, astronomers don’t know how many rogue planets there are or if they’re concentrated in some areas of the galaxy. We’re at the starting line when it comes to figuring these things out. But soon, we may get a better idea.
The Vera Rubin Observatory should see first light by 2023. This powerful observatory will image the entire available sky every few nights, and it’ll do it in fine detail. It houses the largest digital camera ever made: a 3.2 gigabyte CCD.
In Chile, the Vera C. Rubin Observatory is under construction at Cerro Pachon. This image shows construction progress in late 2019. The VCO should be able to spot rogue planets that approach our Solar System. Image Credit: Wil O’Mullaine/LSST CC BY-SA 4.0, https://en.wikipedia.org/w/index.php?curid=62504391
The Vera Rubin will be especially good at detecting transients, that is, anything that changes position or brightness in a couple of days. It’ll have a good chance of spotting any interlopers like rogue planets that might approach our Solar System.
There’s a strong possibility that some of those rogue planets will exhibit unusual emissions or puzzling phenomena. Scientists will probably puzzle over them as they did over Oumuamua.
Maybe another civilization more advanced than us has already faced an existential threat from their dying star. Maybe they made a Herculean effort to capture a rogue planet and engineer it to suit their needs. Maybe they’ve already boarded it and launched it towards a distant, stable, long-lived yellow star, with rocky planets in its habitable zone. Maybe they’re wondering if there’s any life at their destination and how they might be received after their long journey.
0
1
2
3
4
5
- Gemiddelde waardering: 0/5 - (0 Stemmen) Categorie:ALIEN LIFE, UFO- CRASHES, ABDUCTIONS, MEN IN BLACK, ed ( FR. , NL; E )
INTERSTELLAIR REIZEN ZONDER STERRENSCHIP: ALIENS DOEN HET MISSCHIEN!
INTERSTELLAIR REIZEN ZONDER STERRENSCHIP: ALIENS DOEN HET MISSCHIEN!
Caroline Kraaijvanger
Mogelijk reizen aliens niet met sterrenschepen, maar op complete, maar eenzame planeten door de interstellaire ruimte.
Met dat idee komt professor Irina Mullins in het International Journal of Astrobiology op de proppen. “Ik stel voor dat buitenaardse beschavingen ook gebruik kunnen maken van weesplaneten (planeten die niet gebonden zijn aan een ster, maar eenzaam door de ruimte dwalen, red.) als interstellaire transportmiddelen om andere planetaire systemen te bereiken, verkennen en koloniseren.” Dat lijkt misschien een beetje vergezocht, maar er zit een fascinerende gedachtengang achter die ook weer heel interessante implicaties kent. Bijvoorbeeld voor onze zoektocht naar buitenaards leven.
Op reis Aliens kunnen verschillende redenen hebben om hun thuisplaneten te verlaten. Uit nieuwsgierigheid bijvoorbeeld: omdat ze benieuwd zijn naar wat er buiten hun eigen stelsel te vinden is. Of uit noodzaak: omdat een existentiële dreiging – ziekte, klimaatverandering, oorlog, een stervende moederster, etc. – hen dwingt om uit hun vertrouwde omgeving weg te vluchten. Met name in het laatste scenario lopen (ook geavanceerde) aliens echter waarschijnlijk al snel tegen problemen aan, zo schrijft Mullins. “Ze zouden waarschijnlijk op serieuze of onoverkoombare problemen stuiten wanneer ze een ruimtevaartuig willen gebruiken om grote populaties over interstellaire afstanden te transporteren.”
Weesplaneet Het zette Mullins aan het denken. Want hoe zouden geavanceerde beschavingen zich anders kunnen verplaatsen? “En toen bedacht ik dat buitenaardse beschavingen een lift konden krijgen van weesplaneten die door hun planetaire systeem trekken,” zo vertelt ze aan Scientias.nl.
Meeliften op zo’n weesplaneet heeft verschillende voordelen ten opzichte van een sterrenschip. “Weesplaneten kunnen constant zwaartekracht, maar ook veel ruimte en grondstoffen bieden,” zo schrijft Mullins. Denk onder meer aan water aan of net onder het oppervlak van weesplaneten: aliens kunnen het consumeren of gebruiken – bijvoorbeeld door een onderzees habitat te creëren – om zich te beschermen tegen eventuele gevaarlijke straling afkomstig uit de ruimte.
Een lift vinden Maar om mee te kunnen liften op zo’n weesplaneet – en gebruik te kunnen maken van alles wat zo’n planeet te bieden heeft – moet je er natuurlijk eerst wel op zien te komen. Dat kan op verschillende manieren, zo schrijft Mullins. Zo kunnen aliens simpelweg wachten tot zo’n weesplaneet door hun planetaire systeem reist. “Wetenschappelijke studies suggereren dat het aantal weesplaneten weleens groter kan zijn dan het aantal sterren in de Melkweg. Dat vergroot de kans dat weesplaneten door de buitenste regionen van planetaire systemen reizen.” Wanneer aliens die buitenste regionen van hun stelsel gekoloniseerd hebben, hoeven ze met hun ruimtevaartuigen maar een kleine afstand te overbruggen om zo’n passerende weesplaneet te koloniseren.
Heft in eigen hand Het nadeel van die aanpak is natuurlijk wel dat je maar af moet wachten wanneer zo’n weesplaneet op komt dagen. En dat is zeker in het geval van een existentiële dreiging niet ideaal, zo erkent Mullins. Geavanceerde beschavingen kunnen het heft dan ook in eigen hand nemen en op zoek gaan naar een nabije weesplaneet en de koers daarvan aanpassen. “Geavanceerde buitenaardse beschavingen kunnen ook technologieën gebruiken om passerende weesplaneten richting hun planetaire systeem te sturen, zodat hun soort naar de passerende weesplaneet kan reizen.”
Een weesplaneet maken Een andere mogelijkheid is dat aliens naar een (dwerg)planeet in hun eigen planetaire stelsel reizen en deze vervolgens losmaken van de invloed van de moederster, zodat de planeet transformeert tot weesplaneet. “Ze (de aliens, red.) kunnen dan geavanceerde aandrijfsystemen en zwaartekrachtsslingers gebruiken om Sedna-achtige objecten (Sedna is een dwergplaneet aan de rand van ons zonnestelsel, red.) uit hun eigen planetaire systemen te slingeren.” Het is een aanpak die echter alleen voor de geavanceerdere buitenaardse beschavingen is weggelegd. “Met de aandrijfsystemen die daarvoor nodig zijn, zouden de aliens eeuwen voorlopen op onze ruimtetechnologie.”
Een duwtje van de moederster Dwergplaneten kunnen overigens ook door de moederster zelf uit hun planetaire systemen worden gegooid. En wel wanneer zo’n moederster stervende is en transformeert tot een rode reus of supernova. In dat geval is er voor eventuele aliens in het hart van het planetaire stelsel overigens genoeg reden om zich uit de voeten te maken. In theorie zouden ze daarbij relatief dicht bij huis over kunnen stappen op een object met een zeer excentrische (ovaalvormige) baan. Dat object voert ze dan naar de buitenste regionen van hun planetaire stelsel waar ze over kunnen stappen op een dwergplaneet die dan in een later stadium door de stervende moederster uit het planetaire systeem wordt geslingerd en zo een weesplaneet wordt.
Transportmiddel, geen thuis In sommige van de hierboven beschreven scenario’s zijn geavanceerde aandrijfsystemen nodig, in andere niet. Maar in alle scenario’s is het resultaat hetzelfde: de buitenaardse beschavingen eindigen op een planeet die eenzaam door de ruimte dwaalt. Zo’n planeet moeten we echt zien als een alternatief voor het interstellaire sterrenschip en niet als een nieuw thuis, zo benadrukt Miller. Want weesplaneten zijn op lange termijn weinig gastvrij. “Door de afnemende hitteproductie in hun binnenste zullen zulke planeten er niet in slagen om hun met vloeibaar water gevulde oceanen (als die er zijn) te handhaven. Daarnaast hebben weesplaneten minder grondstoffen te bieden dan planetaire systemen. Daarom zouden buitenaardse beschavingen ze ook niet tot hun permanente thuis maken, maar enkel gebruiken als een interstellair transportmiddel waarmee andere planetaire systemen bereikt en gekoloniseerd kunnen worden.”
Sturen Eenmaal op zo’n weesplaneet is het natuurlijk wel zaak dat de aliens uiteindelijk bij een nieuw thuis aanmeren. “Aliens kunnen hun weesplaneet in de interstellaire ruimte sturen door gebruik te maken van aandrijftechnologieën, wellicht aangevuld met zwaartekrachtsslingers,” vertelt Mullins aan Scientias.nl. “Of ze moeten gewoon wachten tot hun weesplaneet een ander planetair systeem op eigen houtje weet te bereiken.”
Aanneembaar scenario? Of aliens zich werkelijk – hun weesplaneet al dan niet bijsturend waar nodig – door het universum verplaatsen, blijft natuurlijk gissen. Maar voor Mullins is het zeker geen ondenkbaar scenario. “Wetenschappelijke studies vertellen ons dat het onmogelijk is om schepen te bouwen waarmee complete beschavingen tussen de sterren kunnen reizen,” zo vertelt ze aan Scientias.nl. “We weten dat sterren sterven als ze ouder worden. We weten dat mensen instinctief hun hachje willen redden en andere beschavingen zouden er ook zo in kunnen staan. Dus wanneer hun moedersterren stervende zijn, zullen geavanceerde intelligente soorten zoeken naar ontsnappingsmogelijkheden. Omdat grote sterrenschepen geen optie zijn, zullen ze naar andere methoden zoeken.” En weesplaneten – of door de aliens tot weesplaneet gemaakte dwergplaneten – zijn dan een logische optie. “Weesplaneten met al hun grondstoffen en oceanen gevuld met water, bieden alles wat buitenaardse wezens tijdens hun interstellaire reizen nodig hebben.”
Op zoek Voor Mullins zijn aliens die meeliften op een weesplaneet dus een reële mogelijkheid. En wat haar betreft, vullen we onze zoektocht naar intelligent buitenaards leven (ook wel aangeduid als SETI) spoedig aan met een zoektocht naar migrerend intelligent leven (Mullins noemt dat: SMETI). “Wetenschappers zoeken traditioneel naar technosignaturen (sporen van buitenaardse technologieën die hinten op de aanwezigheid van intelligent leven, red.) in de leefbare zone van planetaire systemen met daarin een ster die vergelijkbaar of kleiner is dan onze zon. Dat zijn aantrekkelijke plaatsen voor leven. Maar na zestig jaar zoeken hebben we nog steeds niets gevonden. Sommige wetenschappers denken dan ook dat naarmate buitenaardse beschavingen geavanceerder worden, deze hun technologieën zo gebruiken dat ze meer opgaan in hun omgeving en op interstellaire afstanden lastiger detecteerbaar worden.” Maar wanneer zo’n beschaving (noodgedwongen) koers zet naar andere planetaire systemen, moeten er technologieën gebruikt worden die een stuk opvallender zijn en daarmee zou het ook iets gemakkelijker moeten zijn om die aliens op te zoeken.
Alleen moeten we dan wel op een andere plek gaan zoeken; niet nabij zonachtige sterren, maar bijvoorbeeld juist aan de rand van planetaire systemen, alwaar aliens wellicht bezig zijn om een dwergplaneet los te maken van de moederster of juist wachten op een langs scherende weesplaneet. Daarnaast zouden ook door sterren ingevangen weesplaneten goede plaatsen kunnen zijn om op zoek te gaan naar sporen van leven. Net als de omgeving van stervende sterren; daar kunnen zomaar op een dwerg- of weesplaneet gevluchte aliens worden aangetroffen, zo is de gedachte. Het maakt de traditionele zoektocht naar buitenaards leven niet overbodig, zo benadrukt Mullins, maar kan gezien worden als een aanvulling daarop. “Ik zou willen zeggen dat mijn onderzoeksartikel een oproep is om het SETI-programma uit te breiden.”
Ten slotte kan het onderzoek ook implicaties hebben voor ons mensen, want Mullins presenteert een vorm van transport die niet alleen interessant kan zijn voor eventuele aliens, maar waar ook wij (of beter gezegd: ons nageslacht) bij gebaat zou kunnen zijn. “Net als buitenaardse wezens kan de mensheid weesplaneten gebruiken om andere planetaire systemen te bereiken,” stelt Mullins. “Dat zou dan wel iets voor de verre toekomst zijn; wanneer onze ruimtevaarttechnologie veel verder ontwikkeld is.”
Hubble-telescoop ontdekt geïsoleerd en op drift geslagen zwart gat in ons Melkwegstelsel
Naar schatting ‘dwalen’ er zo’n 100 miljoen zwarte gaten rond in ons Melkwegstelsel, maar gezien zwarte gaten geen licht uitzenden, is het extreem moeilijk om ze op te sporen. Dat er nu eentje gevonden werd dat zich met een snelheid van 150.000 kilometer per uur - volledig geïsoleerd - voortbeweegt doorheen ons sterrenstelsel, is vrij uniek.
Het was de Hubble-telescoop van het Amerikaanse en Europese ruimtevaartagentschap NASA en ESA, die het zwarte gat kon detecteren. Deze telescoop heeft al wat prestaties op zijn naam staan, maar slaagt er nu ook voor het eerst in om een (geïsoleerd) zwart gat te vinden dat niet vergezeld wordt door een ster die er rond cirkelt.
Hoe het zwarte gat gevonden werd? Twee onafhankelijke Amerikaanse onderzoeksteams ontdekten dat de ruimte rond het zwarte gat enigszins vervormd was - opnieuw een onzichtbaar verschijnsel. Het licht van een verre ster werd door deze vervormde ruimte echter ook lichtjes afgebogen, en dat is wél waarneembaar. Door de afwijkingen in het licht van deze ster te meten, konden de astronomen enkele eigenschappen van het zwarte gat achterhalen.
Het zwarte gat in kwestie bevindt zich op zo’n 5.000 lichtjaren - de afstand die licht in een periode van één jaar aflegt in een vacuüm - van de aarde. Dat is wel een eindje. Op basis van hun bevindingen schatten astronomen dat het dichtstbijzijnde zwarte gat zo’n 80 jaar van onze aardbol verwijderd is. De dichtstbijzijnde ster is dan weer vier jaar van ons verwijderd. Het licht dat deze ster ‘s nachts geeft, brandde eigenlijk vier jaar geleden al.
Sterrenverslinders
Een zwart gat is wat overblijft na de explosie van een ster, een ster die zwaarder is dan de zon. Tijdens zo’n explosie produceert de ster eventjes zoveel licht als het hele sterrenstelsel waartoe het behoort. Om daarna voor eeuwig zwart te worden. Daarom werden zwarte gaten voor 1964 ‘bevroren sterren’ genoemd. Verder nog wordt de kern van de explosie zo compact dat een zwart gat ontstaat. Omdat er niets aan de zwarte gaten kan ontsnappen - er kan alleen maar wat invallen – groeien ze doorheen de tijd in massa. Zo werd er in september 2019 nog een ster geregistreerd die door zo’n superzwaar zwart gat aan flarden werd gescheurd.
Ook licht ontsnapt niet aan zwarte gaten, in welke golflengte dan ook. Vandaar de naam “zwart gat”. Het object zelf is niet te zien, alleen de straling eromheen.
Astronomen ontdekken snelgroeiend zwart gat dat elke seconde het equivalent van onze aarde opslokt
Astronomen hebben het snelst groeiende zwart gat van de laatste negen miljard jaar ontdekt, zo heeft de Australian National University (ANU) bekendgemaakt. Geen wonder dat het zo snel groeit, het zou elke seconde het equivalent van maar liefst een hele aardbol opslokken.
Het zwarte gat is immens groot, heeft de massa van drie miljard zonnen en het slokt nog elke seconde andere hemellichamen op, aldus het door astronomen van de ANU geleid internationaal team dat het object vond. Volgens hoofdonderzoeker Christopher Onken (ANU) gaat het om een “zeer langverwachte, alsook onverwachte speld in de hooiberg”.
Het zwart gat heeft een visuele magnitude van 14,5. Het is volgens het onderzoeksteam 500 keer groter dan het zwarte gat in ons sterrenstelsel. Iemand met een degelijke telescoop op een donkere plaats moet het gemakkelijk kunnen zien.
Co-auteur Christian Wolf noemde het recordbrekende object een "buitenbeentje. Wij hebben er vrij veel vertrouwen in dat dit record niet zal worden gebroken. Er is eigenlijk geen ruimte meer over voor zulke immense objecten om zich te verschuilen."
“Nu willen we weten waarom dit zwarte gat zo anders is - is er iets catastrofaal gebeurd? Misschien zijn twee grote sterrenstelsels met elkaar in botsing gekomen en is daarbij een heleboel materiaal naar het zwarte gat geleid om het te voeden”, besluit Onken.
Sterrenverslinders
Een zwart gat is wat overblijft na de explosie van een ster, een ster die zwaarder is dan de zon. Tijdens zo’n explosie produceert de ster eventjes zoveel licht als het hele sterrenstelsel waartoe het behoort. Om daarna voor eeuwig zwart te worden. Daarom werden zwarte gaten voor 1964 ‘bevroren sterren’ genoemd. Verder nog wordt de kern van de explosie zo compact dat een zwart gat ontstaat. Omdat er niets aan de zwarte gaten kan ontsnappen - er kan alleen maar wat invallen – groeien ze doorheen de tijd in massa.
Ook licht ontsnapt niet aan zwarte gaten, in welke golflengte dan ook. Vandaar de naam “zwart gat”. Het object zelf is niet te zien, alleen de straling eromheen.
HERBEKIJK
Astronomers capture 1st image of Milky Way's black hole | World Latest News | WION
HERBELUISTER OOK:
What do black holes sound like? NASA releases recording of black hole in distant galaxy
0
1
2
3
4
5
- Gemiddelde waardering: 0/5 - (0 Stemmen) Categorie:HLN.be - Het Laatste Nieuws ( NL)
This is What the Metal Asteroid Psyche Might Look Like
This is What the Metal Asteroid Psyche Might Look Like
If you wanted to do a forensic study of the Solar System, you might head for the main asteroid belt between Mars and Jupiter. That’s where you can find ancient rocks from the Solar System’s early days. Out there in the cold vacuum of space, far from the Sun, asteroids are largely untouched by space weathering. Space scientists sometimes refer to asteroids—and their meteorite fragments that fall to Earth—as time capsules because of the evidence they hold.
The asteroid Psyche is especially interesting, and NASA is sending a mission to investigate the unusual chunk of rock. In advance of that mission, a team of researchers combined observations of Psyche from an array of telescopes and constructed a map of the asteroid’s surface.
Astronomers divide asteroids into three categories. Carbonaceous or C-type asteroids are the most common type. They make up about 75% of known asteroids and contain large amounts of carbon. The carbon makes them dark, and they have low albedoes. Silicaceous or S-type asteroids are the second most common type. They make up about 17% of known asteroids and are mostly made of iron and magnesium silicates.
Metal or M-type asteroids are the rarest types of asteroids and make up about 8% of known asteroids. They appear to contain more metal than the other asteroid types, and scientists think they’re the source of iron meteorites that fall to Earth. M-type meteorites were one of the earliest sources of iron in human history.
King Tut was buried with an iron dagger made from an M-type meteorite. Image: Daniela Comelli/Polytechnic University of Milan
Psyche (16 Psyche) is an M-type asteroid. It’s also called a dwarf planet because it’s about 220 kilometres (140 mi) in diameter. It’s referred to as 16 Psyche because it was the 16th minor planet discovered. (Larger asteroids like Psyche are also known as minor planets.) Psyche is sometimes called the ‘Gold-mine asteroid’ because of the wealth of iron and nickel it contains. Though to be clear, nobody thinks it’s rich in gold.
Visible light images of Psyche don’t tell us much. The European Southern Observatory’s VLT captured some pictures of the asteroid, but they didn’t reveal any detail.
The Very Large Telescope captured this image of 16 Psyche in August 2019. Image Credit: By ESO/Vernazza et al./MISTRAL algorithm (ONERA/CNRS) – Cropped from Kalliope and Psyche, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=111158926
Psyche’s history is a history of uncertainty. For a long time, astronomers thought it was the exposed iron core of a much larger body. In this hypothesis, a powerful collision or series of collisions stripped away the body’s crust and mantle. The larger body would’ve been fully differentiated and measured something like 500 km (310 miles) in diameter. With the crust and mantle gone, only the iron-rich core remained.
That idea fell out of favour as time passed and astronomers continued observing it. Evidence showed that it wasn’t dense enough to be solid iron and is likely porous.
Other researchers suggested that Psyche was disrupted somehow and then re-accreted as a mix of metals and silicates. One study indicated that Psyche isn’t as metal-rich as thought and is more of a rubble pile. In that scenario, collisions with more common C-type asteroids deposited a layer of carbon and other materials onto Psyche’s surface.
The most exotic idea behind Psyche’s origins is the Ferro-volcanic idea. A 2019 study presented evidence that Psyche was once a molten blob. In that scenario, the outer layers cooled and formed stress cracks, and the buoyant molten core erupted as iron volcanoes.
This graphic of 16 Psyche is from a 2021 study. It’s a smoothed, contour-filled optical albedo map with labelled topographical and albedo features. It shows some of the asteroid’s surface features like the depressions Eros, Foxtrot, and Panthia. Names with question marks are indeterminate features. The three blurred white spots are optical bright spots, and the white circles are radar echo centers. Image Credit: Michael K. Shepard et al., Asteroid 16 Psyche: Shape, Features, and Global Map (2021), figure 10. https://iopscience.iop.org/article/10.3847/PSJ/abfdba#psjabfdbaf9, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=113172869
The only way to find out for sure what Psyche is is to go and look at it. So that’s what NASA is doing.
The mission is called Psyche and is scheduled for launch sometime in Fall 2022. The spacecraft will rely on solar-electric propulsion and a gravity-assist maneuver with Mars to arrive at Psyche in 2026. It’ll spend 21 months studying the asteroid and will follow four separate orbital paths, each successive one closer than the previous. As it moves closer to the asteroid, it’ll focus on different scientific objectives.
A team of researchers constructed a new map of Psyche’s surface to help prepare for the mission. The map is in a paper published in the Journal of Geophysical Research: Planets. The title is “The Heterogeneous Surface of Asteroid (16) Psyche,” and the lead author is Saverio Cambioni from MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS).
“Psyche’s surface is very heterogeneous,” Cambioni said in a press release. “It’s an evolved surface, and these maps confirm that metal-rich asteroids are interesting enigmatic worlds. It’s another reason to look forward to the Psyche mission going to the asteroid.”
In this study, the authors used the Atacama Large Millimeter/submillimeter Array (ALMA) to better look at 16 Psyche. ALMA is a radio telescope composed of 66 high-precision antennae. The separate antennae operate together as an interferometer with a high resolution. ALMA operates at wavelengths sensitive to the temperature and some electric properties of materials on Psyche’s surface.
“The signals of the ALMA antennas can be combined into a synthetic signal that’s equivalent to a telescope with a diameter of 16 kilometres (10 miles),” said co-author Katherine de Kleer, an assistant professor of planetary science and astronomy at Caltech. “The larger the telescope, the higher the resolution.”
The new map is based on two types of measurements. One is thermal inertia, which is how long a material takes to reach the temperature of its environment. Higher thermal inertia means it takes longer.
The second is the dielectric constant. The dielectric constant describes how well a material conducts heat, electricity, or sound. A material with a low dielectric constant conducts poorly and is a good insulator and vice versa.
The researchers took the ALMA observations of thermal inertia and dielectric constant and ran hundreds of simulations to see which combinations of materials could explain them. “We ran these simulations area by area so we could catch differences in surface properties,” Cambioni says.
Pure iron has an infinite dielectric constant. By measuring the dielectric constant on Psyche, the researchers could map the surface and locate regions richer in iron. Iron also has high thermal inertia because it’s so dense. So combining thermal inertia and dielectric constant measurements gives a good idea of which surface regions on Psyche are rich in iron and other metals.
This figure from the study shows the thermal inertia (L) and dielectric constant (R) of 16 Psyche’s surface as measured by ALMA. Image Credit: Cambioni et al. 2022.
The researchers call a curious feature on Psyche the Bravo-Golf region. That region has a systematically lower thermal inertia than the highland regions. The Bravo-Golf region is the depression just to the right of the asteroid’s prime meridian in the image below.
This figure from the paper combines thermal inertia with elevation. The low-elevation Bravo-Golf region is visible. Image Credit: Cambioni et al. 2022.
Why does a low-elevation area have lower thermal inertia? Other studies show that the region is also radar-bright. Why is that? The researchers came up with three possibilities.
The lowlands could be metal-rich but covered with fine, porous regolith that lowers their thermal inertia compared to the highlands covered in coarser regolith. Thermal inertial increases with particle size. In this scenario, finer-grained regolith would’ve pooled in the lowlands.
“Ponds of fine-grained materials have been seen on small asteroids, whose gravity is low enough for impacts to shake the surface and cause finer materials to pool,” Cambioni said. “But Psyche is a large body, so if fine-grained materials accumulated on the bottom of the depression, this is interesting and somewhat mysterious.”
The second hypothesis is that the surface material covering the lowlands is more porous than the highlands. Thermal inertia decreases as rock porosity increases. Impact fractures could make the lowlands more porous too.
The third hypothesis is that the lowlands have more silicate-rich materials than the highlands, giving them a lower dielectric constant than some areas of the highlands. The idea is that the Bravo-Golf depression could’ve been formed by an impact with a silicate-rich impactor and left silicate-rich residue behind.
This figure from the study illustrates the three scenarios that might explain the low-thermal-inertia detected in the Bravo-Golf region. Image Credit: Cambioni et al. 2022.
Overall, the study shows that 16 Psyche’s surface is covered in a large variety of materials. It also adds to other evidence showing that the asteroid is metal-rich, though the abundance of metals and silicates varies significantly in different regions. It also suggests that the asteroid might be a remnant core of a differentiated body that lost its mantle and crust long ago. “In conclusion, we provide evidence that Psyche is a metal-rich asteroid whose surface is heterogeneous, shows both metal and silicate materials, and appears evolved by impacts,” the authors conclude.
Simone Marchi is a staff scientist at the Southwest Research Institute and a co-investigator on NASA’s Psyche mission. Marchi wasn’t involved in this study but commented on its significance in a press release. “These data show that Psyche’s surface is heterogeneous, with possible remarkable variations in composition. One of the primary goals of the Psyche mission is to study the composition of the asteroid surface using its gamma rays and neutron spectrometer, and a colour imager. So, the possible presence of compositional heterogeneities is something that the Psyche Science Team is eager to study more.”
This animation from the paper shows thermal inertia on 16 Psyche’s surface. The low-elevation Bravo-Golf region is of particular interest. Credit: Cambioni et al. 2022.
It’ll be up to NASA’s Psyche mission to confirm these findings more rigorously.
But sending a spacecraft all the way to Psyche to understand it in more detail is about more than just Psyche itself.
If Psyche is the remnant core of a rocky, differentiated planetesimal, it’ll reveal something about our planet and how differentiated bodies form. Will it contain some of the same light elements that we expect are in Earth’s core? Earth’s core isn’t dense enough to be pure iron and nickel. Scientists think it contains lighter elements like sulphur, silicon, oxygen, carbon and hydrogen.
The Psyche mission will also determine whether the asteroid formed under conditions more oxidizing or more reducing than Earth’s core. That will tell us more about the solar nebula and the protoplanetary disk.
People sometimes refer to Psyche as the Gold Mine Asteroid because it’s so metal-rich. An object its size would contain an enormous amount of iron, though that value is unlikely to be realized or accessible any time soon.
But if knowledge is as valuable as iron, then 16 Psyche might still be a gold mine.
Andromeda Tore Apart and Consumed a Neighbor Galaxy
Andromeda Tore Apart and Consumed a Neighbor Galaxy
Things may seem quiet and peaceful in the Andromeda Galaxy when you gaze at it in the sky. However, if you know what to look for, there’s evidence of a violent rumble in this galaxy’s past. That’s the takeaway from research by Ivanna Escala, an astronomer at Carnegie Institution for Science in Pasadena. She found telltale clues for a merger a few billion years ago. That’s when Andromeda actively cannibalized another galaxy.
Collisions between galaxies create tidal artifacts with all sorts of shapes. This new work from Ivanna Escala found conclusive evidence that Andromeda’s Northeast, West, and Southeast shelfs and Giant Stellar Stream are the result of a collision with another galaxy. Studying these tidal features can teach us about how galaxies grow and evolve over time as they accrete new material. This composite image of 12 galaxy mergers is courtesy of NASA, ESA, the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University), K. Noll (STScI), and J. Westphal (Caltech).
Mergers Make Galaxies
When galaxies collide (and wouldn’t that be a great movie title?), they basically gobble up material from whatever is around—the galaxies themselves, globular clusters, nebulae, whatever’s in the way. They also shove material around rather violently at times. That produces profound disturbances in the wake of the collision. If you look at the sites of galaxy clashes, you can find knots of star birth, for example. They boil up as material is compressed and shocked by the forces of the collision into active star formation regions.
Collisional Pileups
It also creates stellar associations called tidal features. They can look like streams or arcing shells of stars moving along in the wake of the collision. Sometimes they create “pileups” that look like ripples (or arcs of ripples) similar to when you toss a rock into a pond. If you know how to interpret those clues, you can figure out something about the collisions that caused them.
That’s what Escala and her team did. “The remnants of each crash can be identified by studying the movement of the stars and their chemical compositions,” she explained. “Together this information serves as a kind of fingerprint that identifies stars that joined a galaxy in a collision.”
Diving into Andromeda’s Past
The Andromeda Galaxy is about 10 billion years old. By comparison, the Milky Way Galaxy is about 13.6 billion years old. Like most other galaxies, Andromeda grew by multiple collisions with smaller protogalaxies and subsequent mergers with larger ones. The Milky Way is currently gobbling up at least one dwarf galaxy and also formed by mergers.
The trick to figuring out the merger history is, as any crime scene detective knows, buried in the details. Astronomers look at the chemical components of stars and figure out which are native to the galaxy and which are not. Stellar motions can reveal intruders. If the merger is particularly violent, streams of stars and gas and dust will form observable features.
Digging Into Andromeda’s Stars
Escala and her collaborators looked deep into Andromeda at a feature called the Northeast Shelf. They analyzed 556 red giant branch stars within it. “We performed the first detailed characterization of the chemical composition and geometric motion of the stars in this region of our neighboring galaxy, demonstrating conclusively that the NE shelf is a tidal shell predominately composed of debris from the aftermath of a collision,” Escala explained during a press conference at the American Astronomical Society Meeting in Pasadena, CA.
This image shows NASA/ESA Hubble Space Telescope images of a small part of the giant stellar stream of the Andromeda Galaxy. The stream is a long structure thought to be the remains of a companion galaxy torn apart by the Andromeda Galaxy’s gravity and engulfed in it. By studying details of the stars in the stream, astronomers can determine the chemistry and ages of the stars in each part of the Andromeda Galaxy.
They also showed that this ledge is part of a multi-shell system, along with the galaxy’s west and southeast shelves. The material in these regions is consistent with that of Andromeda’s Giant Stellar Stream, created during the recent large collisions. It’s likely that all those tidal features could have come from the same source. “Our results are in line with modeling that predicted the Giant Stellar Stream is the first loop of material from a collision and the NE shelf is the second layer wrap-around,” Escala concluded. The wrap-around she mentions points toward multiple encounters during the collision/cannibalization event.
Gravitational interactions at the time shaped the streams. The analysis done by Escala and her team is an important step toward confirming predictions about this galaxy’s violent past. Collisions are an important part of that history. More evidence about these actions gives a deeper understanding of the many features left behind long after the merger ends.
The discovery of at least two rocky 'super-Earths' orbiting a nearby dwarf star could provide vital clues in the search for extra-terrestrials, astronomers say.
While the worlds are unlikely to be habitable for life as we know it, the star and its exoplanets are among the closest multi-world systems to Earth, at just 33 light-years away.
This makes the system an excellent target for further investigation, in part because it could contain more planets, including the potential for one in the habitable zone.
'There are many multi-planet systems hosting five or six planets, especially around small stars like this one,' said astrophysicist Avi Shporer, of MIT's Kavli Institute for Astrophysics and Space Research.
'Hopefully we will find more, and one might be in the habitable zone. That's optimistic thinking.'
The discovery of at least two rocky 'super-Earths' (pictured in an artist's impression) orbiting a nearby dwarf star could provide vital clues in the search for extra-terrestrials, astronomers say
KEY FACTS ABOUT THE NEWLY-DISCOVERED 'SUPER-EARTHS'
HD 260655b
Average temperature: 816° Fahrenheit
Orbit time: Circles star every 2.8 days
Size: About 1.2 times as big as Earth
Mass: Twice as massive and slightly denser than Earth
Composition: Terrestrial/rocky
HD 260655c
Average temperature: 543° Fahrenheit
Orbit time: Circles star every 5.7 days
Size:About 1.5 times as big as Earth
Mass:About three Earth masses but a bit less dense
Composition:Terrestrial/rocky
Even though the star HD 260655 is cooler and dimmer than our sun, the proximity of the planets to the red dwarf means the worlds would be way too hot for life.
HD 260655b has an average temperature of 816 degrees Fahrenheit (435 degrees Celsius), while HD 260655c is milder but still a fiery 543 degrees Fahrenheit (284 degrees Celsius).
'We consider that range outside the habitable zone, too hot for liquid water to exist on the surface,' said astronomer Michelle Kunimoto, of MIT's Kavli Institute for Astrophysics and Space Research.
Nevertheless, scientists are excited about this system because the proximity and brightness of its star will give them a closer look at the properties of the planets and signs of any atmosphere they might hold.
'Both planets in this system are each considered among the best targets for atmospheric study because of the brightness of their star,' said Kunimoto.
'Is there a volatile-rich atmosphere around these planets? And are there signs of water or carbon-based species? These planets are fantastic test beds for those explorations.'
The new planetary system was initially identified by NASA's Transiting Exoplanet Survey Satellite (TESS), an MIT-led mission that is designed to observe the nearest and brightest stars, and detect periodic dips in light that could signal a passing planet.
In October 2021, Kunimoto, a member of MIT's TESS science team, was monitoring the satellite's incoming data when she noticed a pair of periodic dips in starlight, or transits, from the star HD 260655.
She ran the detections through the mission's science inspection pipeline, and the signals were soon classified as two TESS Objects of Interest, or TOIs — objects that are flagged as potential planets.
The process of classifying and subsequently confirming new planets can often take several years, but for HD 260655 that process was shortened significantly with the help of archival data.
The fully integrated Transiting Exoplanet Survey Satellite (TESS), which launched in 2018 to find thousands of new planets orbiting other stars
Soon after Kunimoto identified the two potential planets around HD 260655, Shporer looked to see whether the star was observed previously by other telescopes.
As luck would have it, HD 260655 was listed in a survey of stars taken by the High Resolution Echelle Spectrometer (HIRES), an instrument that operates as part of the Keck Observatory in Hawaii.
HIRES had been monitoring the star, along with a host of other stars, since 1998, and the researchers were able to access the survey's publicly available data.
In the end, this collaborative effort quickly confirmed the presence of two planets around HD 260655 in about six months.
The team then looked more closely at TESS data to pin down properties of both planets, including their orbital period and size.
They determined that the inner planet, dubbed HD 260655b, orbits the star every 2.8 days and is about 1.2 times as big as the Earth.
The second outer planet, HD 260655c, orbits every 5.7 days and is 1.5 times as big as the Earth.
From the archival data, researchers were then able to calculate the planets' mass and density.
They found the inner planet is about twice as massive and slightly denser than Earth, while the outer planet is about three Earth masses but a bit less dense. Both planets, based on their density, are likely terrestrial, or rocky in composition, the astronomers said.
So far, more than 5,000 exoplanets have been confirmed in our Milky Way galaxy, with experts especially interested in finding terrestrial, or rocky, worlds like Earth, Venus, and Mars.
NASA's 'planet hunter,' spacecraft, is equipped with four cameras that will allow it to view 85 per cent of the entire sky, as it searches exoplanets orbiting stars less than 300 light-years away.
By studying objects much brighter than the Kepler targets, it's hoped TESS could uncover new clues on the possibility of life elsewhere in the universe.
Its four wide-field cameras will view the sky in 26 segments, each of which it will observe one by one.
In its first year of operation, it mapped the 13 sectors that make up the southern sky, and scoured the northern sectors the following year.
Since it was launched in 2018, TESS has found over 170 confirmed exoplanets, and has a catalogue of over 4,700 yet to be verified.
It has also discovered other strange phenomena including supernova and triple star systems since it was launched.
Tess is 5 feet (1.5 meters) wide and is shorter than most adults.
The observatory is 4 feet across (1.2 meters), not counting the solar wings, which are folded for launch, and weighs just 800 pounds (362 kilograms).
NASA says it's somewhere between the size of a refrigerator and a stacked washer and dryer.
NASA has confirmed that there are more than 5,000 known planets outside our solar system, known as exoplanets.
The US space agency has added another 65 exoplanets to the online NASAExoplanet Archive, bringing the grand total to 5,005.
Exoplanets found so far include small, rocky worlds like Earth, gas giants many times larger than Jupiter, and 'hot Jupiters' in scorchingly close orbits around their stars.
However, NASA stresses that 5,005 is only 'a tiny fraction' of all the planets in the Milky Way galaxy alone, which could number hundreds of billions.
NASA confirms there are more than 5,000 planets beyond our solar system including several 'hot Jupiters', 'super-Earths' and 'mini-Neptunes'. An artist's impression of the variety of different exoplanets are depicted here
HOW MANY EXOPLANETS ARE THERE?
An exoplanet is any planet beyond our solar system. Most orbit other stars, but free-floating exoplanets, called rogue planets, orbit the galactic center and are untethered to any star.
5,005 exoplanets have been confirmed since the first exoplanet discoveries in the early 1990s, as of March 22, 2022.
The majority of these exoplanets are gaseous, like Jupiter or Neptune, rather than terrestrial, according toNASA's online database.
The closest exoplanet is called Proxima Centauri b, around 4.2 light years away from our Sun.
'It's not just a number,' said Jessie Christiansen, research scientist with the NASA Exoplanet Science Institute at Caltech in Pasadena, California.
'Each one of them is a new world, a brand-new planet. I get excited about every one because we don't know anything about them.'
The majority of exoplanets are gaseous, like Jupiter or Neptune, rather than terrestrial, according to NASA's online database.
The archive records exoplanet discoveries that appear in peer-reviewed, scientific papers that have been confirmed using multiple detection methods or by analytical techniques.
Among the most recently confirmed exoplanets are K2-377 b, a 'super Earth' with a mass of 3.51 Earths that takes 12.8 days to complete one orbit of its star.
Another, called TOI-1064 b, is a 'potentially rocky world larger than Earth, according to NASA.
Most exoplanets are found by measuring the dimming of a star that happens to have a planet pass in front of it, called the transit method.
Another way to detect exoplanets, called the Doppler method, measures the 'wobbling' of stars due to the gravitational pull of orbiting planets.
The more than 5,000 exoplanets confirmed in our galaxy so far include a variety of types - among them a mysterious variety known as 'super-Earths' because they are larger than our world and possibly rocky
NASA's milestone comes 30 years after the first exoplanets were discovered, back in 1992.
THREE 'EXOPLANETS' ARE ACTUALLY STARS
Scientists have been examining the thousands of exoplanet discoveries confirmed within the Milky Way Galaxy, and three of them have turned out to be stars.
A team from MIT in Cambridge looked through planets discovered using the NASA Kepler Space Telescope, double checking the measurements to see which match known planet sizes.
They identified three objects that are simply too big to be planets, based on new, more accurate measurements taken by the European Space Agency Gaia telescope.
In January that year, Aleksander Wolszczan and Dale Frail announced the discovery of two rocky planets orbiting PSR B1 257+12, a pulsar in the constellation Virgo. A further planet was discovered in the system in 1994.
Finding just three planets around this spinning star essentially opened the floodgates for exoplanets, said Wolszczan, who still searches for exoplanets as a professor at Penn State.
'If you can find planets around a neutron star, planets have to be basically everywhere,' he told NASA. 'The planet production process has to be very robust.'
Some of the exoplanets that have been discovered since, such as Kepler 16-b, orbit two stars at once, like the planet of Tatooine in 'Star Wars'.
Around 200 light years away, Kepler-16b weighs about a third as much as Jupiter and has a radius three-fourths that of Jupiter, making it similar to Saturn in both size and mass.
Another exoplanet called WASP-121b, around 850 light years from Earth, is an example of a 'hot Jupiter' – a Jupiter-like giant gas planet on a close orbit around its parent star.
WASP-121b has one of the shortest orbits detected to date, circling its star in just 30 hours.
It is tidally locked, meaning the same side always faces its star, while its colder 'night' side is turned forever toward space.
Gliese 486b, meanwhile, is an example of a 'super Earth' – a planet larger than Earth but smaller than the four gas giants Jupiter, Saturn, Neptune and Uranus.
Some exoplanets orbit two stars at once, like the planet of Tatooine in the 1977 film 'Star Wars' (pictured)
Artist's impression of exoplanet Kepler-16b, the most 'Tatooine-like' planet yet found in our galaxy. Kepler-16b is depicted as a small black circle circling two stars. The largest of the two stars, a K dwarf, is about 69 per cent the mass of our sun, and the smallest, a red dwarf, is about 20 per cent the sun's mass
Gliese 486b is the only planet so far detected orbiting the small star and has a radius 1.3 times larger than the Earth but is 2.8 times more massive.
The planet has an iron-silicate composition similar to the makeup of Earth but is much hotter, with a surface temperature of 802°F (428°C), according to a 2021 study.
GJ 367 b, meanwhile, is exposed to a huge amount of radiation, due to its small distance to its star – about 620,000 miles – which it orbits in just eight hours.
With a diameter of 5,560 miles, GJ 367 b is slightly bigger than Mars (4,200 miles) but has the makeup of Mercury.
NASA said its James Webb Space Telescope (depicted here in space) will capture light from atmospheres of exoplanets to read which gases are present to potentially identify tell-tale signs of habitable conditions
Scientists are still trying to learn more about what exactly exoplanets and their atmospheres are made up of.
NASA said its James Webb Space Telescope will capture light from the atmospheres of exoplanets to read which gases are present to potentially identify tell-tale signs of habitable conditions.
The $10 billion (£7.4 billion) observatory, which launched on Christmas Day, will explore the universe in the infrared spectrum, allowing it to gaze through clouds of gas and dust where stars are being born.
EXOPLANETS HAVE 'EXOTIC' ROCKS THAT CAN'T BE FOUND IN OUR SOLAR SYSTEM
Rocky planets outside our solar system, known as exoplanets, are composed of 'exotic' rock types that don't even exist in our planetary system, a 2021 study shows.
Researchers have used telescope data to analyse white dwarfs – former stars that were once gave life just like our Sun – in an attempt to discover secrets of their former surrounding planets.
Roughly 98 per cent of all the stars in the universe will ultimately end up as white dwarfs, including our own Sun.
The experts found that some exoplanets have rock types that don't exist, or just can't be found, on planets in our solar system.
These rock types are so 'strange' that the authors have had to create new names for them – including 'quartz pyroxenites' and 'periclase dunites'.
Some 4,374 exoplanets have been confirmed in 3,234 systems since the first exoplanet discoveries in the early 1990s.
The majority of these exoplanets are gaseous, like Jupiter or Neptune, rather than terrestrial, according to NASA's online database.
Two New Rocky Planets Discovered Close to the Solar System
Two New Rocky Planets Discovered Close to the Solar System
TESS has struck paydirt again. NASA’s planet-hunting spacecraft has found two new super-Earths orbiting a star only 33 light-years away. These are two of the closest rocky planets ever found.
The star’s name is HD 260655. It’s a bright M dwarf star, sometimes called a red dwarf. Both planets are rocky super-Earths, and though the word “Earth” is suggestive, neither world is likely to support life due to their extremely high temperatures. But scientists still think they’re worthy of further observations.
A new paper titled “The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 PC” announced the discovery. The lead author is Rafael Luque of the Institute of Astrophysics of Andalusia, Spain, and the University of Chicago. The journal Astronomy and Astrophysics will publish the paper, but it’s currently available online at the pre-press site arxiv.org.
HD 260655b is closest to the star with an orbital period of 2.7 days. Its radius is 1.2 Earth radii, and its mass is 2.14 Earth masses.
HD 260655c has an orbital period of 5.7 days. Its radius is 1.5 Earth radii, and its mass is 3.09 Earth masses.
Their temperatures are almost certainly too high to support any life. Planet b’s temperature is approximately 435 Celsius (816 Fahrenheit), and planet c’s temperature is about 284 Celsius (543 Fahrenheit.) Those temperature estimates are dependent on any atmospheres the planets may have.
Their potential atmospheres are part of what makes these planets interesting.
“The HD 260655 system presents a unique opportunity for comparative planetology studies of rocky worlds.”
From “The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 PC.”
When the James Webb Space Telescope begins science operations (soon, people, soon), it’ll have the capability to examine the atmospheres of exoplanets like these. The results will show us how different rocky planets can be from each other and will provide clues to how rocky planets form.
The opportunity to study two rocky planets in the same system is too good to pass up.
“Multiplanetary systems offer a unique opportunity for characterization via comparative planetology, as they have formed within the same protoplanetary disk,” the authors write. And since the host star is so small, only about 0.4 solar masses, the super-Earths exhibit more influence on it. This makes measuring the planets’ masses and densities easier.
The star is a red dwarf, and it’s much dimmer than a star like our Sun. But for its type, HD 260655 is pretty bright. “It is among the brightest early-type M dwarfs in the sky, with an apparent magnitude in the J band of 6.7 mag.,” the authors write. The J-band is in the near-infrared, part of the electromagnetic spectrum that James Webb is designed to observe.
And at only 33 light-years away, the JWST easily has the power to examine the planets’ atmospheres spectroscopically. The telescope’s Near-Infrared spectrograph (NIRSpec) can perform three types of spectroscopic observations in the NIR. It can obtain the spectra of over 100 targets simultaneously in one of its modes. Combined with its other instruments and modes, no exoplanet atmosphere will be safe. Certainly none at this distance anyway.
But decisions on which planets are suitable for atmospheric characterization by the JWST come down to specific metrics. The authors computed two values for these rocky exoplanets and compared them to their peers in NASA’s Exoplanet Archive. The values are the Transmission Spectroscopy Metric (TSM) and Emission Spectroscopy Metric (ESM.) Both planets are in the top quartile of desirable targets for JWST spectroscopy. HD 260655 b is among the top 10 terrestrial planets for atmospheric characterization. (Note that in this metric, the inner planet (HD 260655 b) is considered a terrestrial planet and the outer planet (HD 260655 c) is regarded as a super-Earth/sub-Neptune.)
This figure from the study shows the Transmission Spectroscopy Metric (TSM) for both rocky super-Earths compared to their peers in NASA’s Exoplanet Archive. These numbers place both targets in the top quartile in their respective categories, making them excellent candidates for follow-up spectroscopy with the JWST. Image Credit: Luque et al. 2022.
For these reasons, the team behind this discovery says that the pair of super-Earths are among the top 10 terrestrial exoplanet candidates for atmospheric characterization. There’s no certainty that the planets have atmospheres, but there’s some reason to believe they do. Because even though they were discovered with TESS, which detects exoplanet transits, the team used data from other ground-based facilities to learn as much as possible.
The team measured the wobble exhibited by the star as the orbiting planets tugged on it. Those measurements reveal the planets’ masses. By combining their masses with their sizes, the researchers found their densities. That led to the conclusion that they’re rocky planets. It also means that if the planets do have atmospheres, they’re likely not extended hydrogen atmospheres.
This figure from the study shows HD 260655 b and c in the context of other transiting exoplanets with well-known masses. Planets orbiting red dwarfs are shown in orange, while others are in grey. It also shows theoretical models for their internal compositions. Image Credit: Luque et al. 2022.
The team surmised that the inner planet, HD 260655 b, has a bulk density composition in perfect agreement with Earth’s. But planet c is different. “HD 260655 c is more consistent with an internal composition void of iron and fully made of silicates if it is assumed to be free of volatiles,” the paper states. The team says that the density difference between the planets is either due to different concentrations of volatiles or to observational uncertainties.
Another interesting fact about these planets concerns what exoplanet scientists call the small planet radius gap. It’s an “… observed scarcity of planets with radii between 1.5 and 2 times Earth’s radius,” as Wikipedia defines it. Scientists think that the gap could be due to photoevaporation. Different researchers have defined the gap differently in terms of planet radii, but both planets in the system are less than 1.5 Earth radii. This suggests that both worlds have lost their atmospheres, which is expected for planets this close to their stars.
The two grey lines represent the small planet radius gap as defined by different researchers. Both HD 260655 b and c are in the gap, meaning they’ve likely had their atmospheres stripped away by the star. Image Credit: Luque et al. 2022.
This paper shows that planet c’s atmosphere, if it had one, was likely a Hydrogen/Helium atmosphere that was stripped away. But if they’re wrong about the composition, and it’s more like Earth’s, then it may have held on to a water-dominated atmosphere.
Planet b is different. Since it’s so much closer to its star, it’s unlikely to have much of an atmosphere. In both cases, if the planets have atmospheres, they’re highly unlikely to have extended hydrogen atmospheres.
These planets are not targets in the search for life. They’re too hot. But they’re scientifically desirable targets in other ways. “The HD 260655 system presents a unique opportunity for comparative planetology studies of rocky worlds,” the authors write. As pointed out earlier, they’re both prime targets for follow-up spectroscopy with the JWST. “These follow-up observations will improve our knowledge about the formation and evolution history of the system,” the authors write. Those observations could “… open a new observational avenue to study the magnetic fields of low-mass stars and their imprint in planetary systems.”
An artist’s conception of a superflare event on a dwarf star. Image credit: Mark Garlick/University of Warwick
Evidence from HARPS (High Accuracy Radial Velocity Planet Searcher) shows that 40% of red dwarfs host Earth-like planets in their habitable zones. The problem is that red dwarfs can flare violently, rendering their habitable zone uninhabitable, or so we think. But we just don’t have a complete picture.
So while these two planets are far too hot for surface water and life, astronomers can use them to learn more about all those other planets orbiting all those other red dwarfs.
Richard Dolan on USOs consistently seen in Earth's bodies of water
Richard Dolan on USOs consistently seen in Earth's bodies of water
We live in a world of deceptive narratives coming from the very sources we were once taught to trust. One of those narratives deals with UFOs.
Something completely left out of our public discussion of the UFO phenomenon are those objects consistently seen in Earth's bodies of water.
These UFOs/USOs flying into and out of the oceans, unknown craft that are able to travel underwater, so it’s quite possible that there are some UFO/USO (whether of extraterrestrial origin or military) bases hidden deep within the oceans.
Another remarkable detail, most of these underwater bases are located off coast and connected via tunnels with a base on land which indicates that such secret underwater bases are built by governments or certain organizations who are working together with extraterrestrials.
Unidentified Submersible Objects (USOs) have been with us for as long as airborne UFOs have. We need to recognize and understand this.
What better place to have an impenetrable base than deep within the oceans of the planet.
Ancient Astronaut Theorists believe aliens might’ve crashed landed in Russia based on mind boggling evidence, in this clip from Season 15, “The Relics of Roswell.”
Astronomers Caught Betelgeuse Just Before it Started Dimming and Might Have Seen a Pressure Wave Rippling Through its Atmosphere
Astronomers Caught Betelgeuse Just Before it Started Dimming and Might Have Seen a Pressure Wave Rippling Through its Atmosphere
A couple of years ago, Betelgeuse generated much interest when it started dimming. That caught the attention of astronomers worldwide, who tried to understand what was happening. Was it about to go supernova?
Evidence showed that dust was the most likely culprit for the red supergiant’s dimming, though there are still questions. A new study shows that the star was behaving strangely just before the dimming.
The optical dimming that Betelgeuse—or Alpha Orionis—exhibited in late 2019 and early 2020 was unprecedented. Betelgeuse often undergoes periodic optical dimming, which happens in timescales of ~300-500 days and ~2000 days. But the Great Dimming, as it came to be known—when the star dimmed to about two-thirds of its normal brightness— was the faintest that the star had become in almost 200 years of observations.
Researchers got to work generating possible explanations for the dimming. Some hypothesized that dust caused the dimming, others hypothesized that a reduction in photosphere temperature caused it, and some thought both played a role.
Astronomers continued studying it, and evidence showed that temperature decrease alone couldn’t be the culprit. Episodic mass loss was proposed as the cause, paired with a rise in large grain dust in the line of sight. Others argued that large inhomogeneities in the photosphere caused the dimming. Another suggested a critical shift in Betelgeuse’s pulsation dynamics caused the Great Dimming. If feedback from UT readers is any indication, there’s still confusion around the cause of the dimming event.
Betelgeuse, as seen by the Hubble Space Telescope. Credit: NASA
But there were really two dimming events, and that’s helped create some of the confusion. The scientific community has settled on dust as the cause of the first dimming. “We know the first dimming event involved a dust cloud,” said Dr. Meridith Joyce from The Australian National University in 2020.
According to Dr. Joyce, the second dimming event had a different cause: “We found the second smaller event was likely due to the pulsations of the star.”
Now a new paper presents observations of Betelgeuse just before the Great Dimming. Its title is “SPATIALLY RESOLVED OBSERVATIONS OF BETELGEUSE AT ?7 MM AND ?1.3 CM JUST PRIOR TO THE GREAT DIMMING.” The Astrophysical Journal will publish it, but for now, it’s available on the pre-press site arxiv.org. The authors are Dr. Lynn D. Matthews of MIT’s Haystack Observatory and Andrea Dupree from the Harvard and Smithsonian Center for Astrophysics. The paper is based on observations of Betelgeuse with the Karl G. Jansky Very Large Array.
“Our measurements suggest recent changes in the temperature and density structure of the atmosphere,” the authors write. The star’s photosphere “… is ~20% dimmer than in previously published observing epochs between 1996–2004.” This is … lower than previously reported temperatures at comparable radii and >1200 K lower than predicted by previous semi-empirical models of the atmosphere.”
Betelgeuse is known for pulsating, as it swells and shrinks symmetrically. These are Hubble images of the star from 1998 and 1999. Image Credit: NASA/ESA/Hubble
The researchers also found that the measured brightness temperature was cooler than expected and that there were “… no obvious signatures of giant convective cells or other surface features.” The star’s brightness profile was also more complex than a uniform elliptical disk (A uniform elliptical disk is a tool astrophysicists use to characterize the mean properties of a star.) Their observations were from about six weeks before ultraviolet measurements found increases in electron density in Betelgeuse’s southern hemisphere, coupled with a large-scale outflow.
So what does all that mean?
“We discuss possible scenarios linking these events with the observed radio properties of the star, including the passage of a strong shock wave.”
Researchers in the astrophysical community have postulated that a shock wave could’ve caused the Great Dimming. A 2021 paper found that Betelgeuse’s photosphere experienced successive shock waves in February 2018 and January 2019, with the initial shock amplifying the second one. Other research showed that a shock wave passed through the southwestern portion of Betelgeuse’s chromosphere between 2019 September and November. Since the photosphere is under the chromosphere, it’s reasonable to think that the two shock waves are related.
This diagram of a star’s layers shows how the photosphere is below the chromosphere. The photosphere is the lowest layer of a star’s atmosphere and the lowest observable layer. Image Credit: ESA
The researchers say they can’t conclude that their observations are directly responsible for the Great Dimming, even though their data suggests “… recent changes in the density and/or temperature structure of the atmosphere…” But a large-amplitude shock or pressure wave passing through Betelgeuse’s atmosphere could cause changes in density and temperature.
The authors are cautious and inconclusive, but they do point out that the pressure wave they observed could’ve caused Betelgeuse’s Great Dimming. “Such an event may be linked to a largescale mass ejection from the star that has been postulated as an explanation for the steep decline in optical magnitude associated with the Great Dimming.”
There’s no question that Betelgeuse will explode as a Type IIP supernova, likely in the next 100,000 years or so. It’s the 10th brightest star in the night sky and is giving astronomers an opportunity to study intensely the behaviour of a star as it approaches its cataclysmic end.
The familiar constellation of Orion. Orion’s Belt can be clearly seen, as well as Betelgeuse (red star in the upper left corner) and Rigel (bright blue star in the lower right corner). Credit: NASA Astronomy Picture of the Day Collection NASA
This study won’t be the final word on Betelgeuse and its dynamic behaviour. The star is still up there, anchoring the Orion the Hunter’s right shoulder. Generations and generations of astronomers are bound to keep watching it.
If humanity lasts long enough, our distant descendants will get to watch it explode.
Beste bezoeker, Heb je zelf al ooit een vreemde waarneming gedaan, laat dit dan even weten via email aan Frederick Delaere opwww.ufomeldpunt.be. Deze onderzoekers behandelen jouw melding in volledige anonimiteit en met alle respect voor jouw privacy. Ze zijn kritisch, objectief maar open minded aangelegd en zullen jou steeds een verklaring geven voor jouw waarneming! DUS AARZEL NIET, ALS JE EEN ANTWOORD OP JOUW VRAGEN WENST, CONTACTEER FREDERICK. BIJ VOORBAAT DANK...
Druk op onderstaande knop om je bestand , jouw artikel naar mij te verzenden. INDIEN HET DE MOEITE WAARD IS, PLAATS IK HET OP DE BLOG ONDER DIVERSEN MET JOUW NAAM...
Druk op onderstaande knop om een berichtje achter te laten in mijn gastenboek
Alvast bedankt voor al jouw bezoekjes en jouw reacties. Nog een prettige dag verder!!!
Over mijzelf
Ik ben Pieter, en gebruik soms ook wel de schuilnaam Peter2011.
Ik ben een man en woon in Linter (België) en mijn beroep is Ik ben op rust..
Ik ben geboren op 18/10/1950 en ben nu dus 74 jaar jong.
Mijn hobby's zijn: Ufologie en andere esoterische onderwerpen.
Op deze blog vind je onder artikels, werk van mezelf. Mijn dank gaat ook naar André, Ingrid, Oliver, Paul, Vincent, Georges Filer en MUFON voor de bijdragen voor de verschillende categorieën...
Veel leesplezier en geef je mening over deze blog.
(193).jpg)
.jpg)
(21).jpg)
Meet Ross 508b: Scientists discover a 'SUPER EARTH'...
'Super-Earth' covered in oceans of LAVA and another...
Could life on Earth have arrived on an asteroid 3.8 billion...
Deep freeze: New form of ICE discovered that may be common...
That's no planet! Astronomers re-examine thousands of alien...
NASA's James Webb Space Telescope is photographed 620,000...
Photobombing a star! Thousands of distant and ancient...
