Dit is ons nieuw hondje Kira, een kruising van een waterhond en een Podenko. Ze is sinds 7 februari 2024 bij ons en druk bezig ons hart te veroveren. Het is een lief, aanhankelijk hondje, dat zich op een week snel aan ons heeft aangepast. Ze is heel vinnig en nieuwsgierig, een heel ander hondje dan Noleke.
This is our new dog Kira, a cross between a water dog and a Podenko. She has been with us since February 7, 2024 and is busy winning our hearts. She is a sweet, affectionate dog who quickly adapted to us within a week. She is very quick and curious, a very different dog than Noleke.
DEAR VISITOR,
MY BLOG EXISTS NEARLY 13 YEARS AND 4 MONTH.
ON /30/09/2024 MORE THAN 2.230.520
VISITORS FROM 135 DIFFERENT NATIONS ALREADY FOUND THEIR WAY TO MY BLOG.
THAT IS AN AVERAGE OF 400GUESTS PER DAY.
THANK YOU FOR VISITING MY BLOG AND HOPE YOU ENJOY EACH TIME.
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 In België had je vooral BUFON of het Belgisch UFO-Netwerk, dat zich met UFO's bezighoudt. BEZOEK DUS ZEKER VOOR ALLE OBJECTIEVE INFORMATIE , enkel nog beschikbaar via Facebook en deze blog.
Verder heb je ook het Belgisch-Ufo-meldpunt en Caelestia, die prachtig, doch ZEER kritisch werk leveren, ja soms zelfs héél sceptisch...
Voor Nederland kan je de mooie site www.ufowijzer.nl bezoeken van Paul Harmans. Een mooie site met veel informatie en artikels.
MUFON of het Mutual UFO Network Inc is een Amerikaanse UFO-vereniging met afdelingen in alle USA-staten en diverse landen.
MUFON's mission is the analytical and scientific investigation of the UFO- Phenomenon for the benefit of humanity...
Je kan ook hun site bekijken onder www.mufon.com.
Ze geven een maandelijks tijdschrift uit, namelijk The MUFON UFO-Journal.
Since 02/01/2020 is Pieter ex-president (=voorzitter) of BUFON, but also ex-National Director MUFON / Flanders and the Netherlands. We work together with the French MUFON Reseau MUFON/EUROP.
ER IS EEN NIEUWE GROEPERING DIE ZICH BUFON NOEMT, MAAR DIE HEBBEN NIETS MET ONZE GROEP TE MAKEN. DEZE COLLEGA'S GEBRUIKEN DE NAAM BUFON VOOR HUN SITE... Ik wens hen veel succes met de verdere uitbouw van hun groep. Zij kunnen de naam BUFON wel geregistreerd hebben, maar het rijke verleden van BUFON kunnen ze niet wegnemen...
21-01-2021
CIA Drops ‘Black Vault’ Trove Containing ‘All’ Government Documents On UFOs
CIA Drops ‘Black Vault’ Trove Containing ‘All’ Government Documents On UFOs
The CIA has released all publicly available U.S. government documents collected on unidentified flying objects (UFO) over the course of three decades that can now be downloaded by any curious users.
According to reports, the massive trove of data on UFOs includes over 2,700 pages of information collected and recorded by government agencies over the course of decades, with some declassified documents dating back as far as the 1980s.
The information was released thanks to numerous requests filed under the Freedom of Information Act (FOIA) over the past 25 years.
The downloadable archives are available on the website The Black Vault, which has collected every piece of data recording sightings of UFOs. The site’s founder, John Greenewald Jr., purchased a disc which the CIA claims contains the entirety of its archives, but Greenewald notes that “there may be no way to entirely verify that.”
“Research by The Black Vault will continue to see if there are additional documents still uncovered within the CIA’s holdings,” Greenewald added.
The U.S. government has been increasingly open in its discussions of UFOs since September 2019, when the U.S. Navy admitted that widely-circulated video footage captured by Navy pilots purportedly showing UFOs flying through the skies did depict actual “unknown” objects that flew into U.S. airspace.
While officials admitted that they have been baffled by the unknown flying objects, they also admit that past encounters with them have been frequent. They also said that rather than calling them “UFOs,” they prefer the term unidentified aerial phenomena or UAPs.
The Guardian reports that a range of bizarre incidents are recorded in the documents, some of which are hard to decipher and are extremely disorganized.
One document reports a series of inexplicable explosions in a Russian town, while another reports a first-hand account of a sighting of an unidentified aerial phenomenon near Baku, the capital of Azerbaijan.
LiveScience has also reviewed the files, and reports that the documents cover a range of other incidents such as a “1976 account of the government’s then-Assistant Deputy Director for Science and Technology being hand-delivered a mysterious piece of intelligence on a UFO.”
However, Greenewald has expressed annoyance over the manner in which the agency packaged the documents, including the fact that they were burned onto CD-ROM, a medium that he called “outdated.”
“The CIA has made it INCREDIBLY difficult to use their records in a reasonable manner,” he wrote to Vice’s Motherboard. “This outdated format makes it very difficult for people to see the documents, and use them, for any research purpose.”
The arrival of the dump comes as UFOlogists and alien aficionados eagerly anticipate hearings before Congress where Pentagon and intelligence agency officials will report all of their findings on UAPs, according to the New York Post.
A provision tucked into the roughly 5,600-page coronavirus relief bill passed in December requires that government agencies “submit a report within 180 days … to the congressional intelligence and armed services committees on unidentified aerial phenomena.”
Also last June, outgoing President Trump told his son Don Trump Jr. that he had heard some “interesting” things about supposed UFOs and the secretive Area 51 base near Roswell, New Mexico, that some theorists claim was a crash site for a UFO.
Nikola Tesla Secrets You Had No Idea About, Death Ray, Particle Weapon, Plasma Lasers, Marc Seifer
Nikola Tesla Secrets You Had No Idea About, Death Ray, Particle Weapon, Plasma Lasers, Marc Seifer
Nikola Tesla Secrets You Had No Idea About, Death Ray, Particle Weapon, Plasma Lasers, Marc Seifer
Dr. Marc Seifer is the preeminent authority on the life and times of Nikola Tesla as evidenced through his exhaustively researched best seller: Wizard. Dr. Seifer ’s wide ranging and meticulously researched published articles, novels and books span subjects ranging from metaphysics, behavior analysis to science fiction.
Besides his authoring, he is a forensic expert and published master of handwriting analysis.
Nikola Tesla, Ether, Gravity & Dark Matter Explained, Marc Seifer
Nikola Tesla, Ether, Gravity & Dark Matter Explained, Marc Seifer
Nikola Tesla, Ether, Gravity & Dark Matter Explained, Marc Seifer
Dr. Marc Seifer is the preeminent authority on the life and times of Nikola Tesla as evidenced through his exhaustively researched best seller: Wizard. Dr. Seifer ’s wide ranging and meticulously researched published articles, novels and books span subjects ranging from metaphysics, behavior analysis to science fiction. Besides his authoring, he is a forensic expert and published master of handwriting analysis.
Near collision with UFO captured on camera by airline passenger
Near collision with UFO captured on camera by airline passenger
Passenger captured a UFO on video while on board the Singapore Airlines plane heading to Zurich Airport. The passenger was about to record the landing but after minutes he witnessed a near collision with a UFO.
This video proves that the pilot is aware and prepared to dodge the UFO. The pilot followed safety protocol, the engines roared, and passengers panicked.
The pilot managed to avoid the unidentified flying object and made a safe landing at Zurich Airport later on. Date and time of the event: January 17th, 2021 between 7:30 and 7:50 am.
RELATED INFORMATION, selected and posted by peter2011
Here's what discovered about that alleged "Near collision with UFO captured on camera by Singapore Airlines passenger". Details in comments
Three lights appeared over South Carolina 20-Jan-2021
Three lights appeared over South Carolina 20-Jan-2021
This was filmed over Myrtle Beach in South Carolina on 20th January 2021 at 7:30pm.
Witness report:
After seeing all of the replies of flairs I should probably add this happened multiple times, around the exact same place. I had already seen these lights twice by the time I took this video.
Bright UFO making maneuvers over Colton, CA 19-Jan-2021
Bright UFO making maneuvers over Colton, CA 19-Jan-2021
This bright unidentified flying object was flying over Colton, California on 19th January 2021.
Witness report:
Witnessed a bright light moving at variable speeds, direction, heights and brightness for a few minutes. Remembered to record a video using my phone after viewing for awhile and took a 1minute, 28 second video. The light was flying around the flight path for Ontario Airport arriving and departing aircraft although non were witnessed during this event.
Virgin Orbit's LauncherOne rocket blasts its way toward space after separating from its carrier plane during the successful Launch Demo 2 mission on Jan. 17, 2021.
"Payloads successfully deployed into our target orbit! We are so, so proud to say that LauncherOne has now completed its first mission to space, carrying 9 cubesat missions into low Earth orbit for our friends @NASA. #LaunchDemo2," Virgin Orbit announced via Twitter today. (One of the nine missions featured two cubesats, so the total number of spacecraft lofted was 10.)
The 70-foot-long (21 meters), two-stage LauncherOne, which is capable of delivering up to 1,100 lbs. (500 kilograms) to orbit, took off from California's Mojave Air and Space Port today at about 1:50 p.m. EST (1850 GMT; 10:50 a.m. local California time). The rocket left the ground beneath the wing of its Boeing 747 carrier plane, known as Cosmic Girl.
This air-launch strategy — which Virgin Orbit's sister company Virgin Galactic also employs with its suborbital space plane, SpaceShipTwo — increases flexibility and responsiveness compared to traditional vertically launched rockets, Virgin Orbit representatives have said.
Pilots Kelly Latimer and Todd Ericson took Cosmic Girl southwest, cruising out over the Pacific Ocean toward a drop point about 50 miles (80 kilometers) south of the Channel Island. About an hour after liftoff, at an altitude of roughly 35,000 feet (10,700 m), LauncherOne separated from the plane, then lit up its first-stage NewtonThree engine to make its own way to space.
But today, LauncherOne just kept on checking boxes. The rocket's upper stage separated successfully and fired its NewtonFour engine as planned, and LauncherOne slipped into orbit around our planet.
Virgin Orbit's LauncherOne rocket lifts off beneath the wing of the Cosmic Girl carrier plane from California's Mojave Air and Space Port on Jan. 17, 2021. (Image credit: Virgin Orbit via Twitter)
About 45 minutes after its first burn, the NewtonFour blazed up again, circularizing the upper stage's orbit. Shortly thereafter, the upper stage deployed the 10 tiny satellites, which were provided by eight different university groups and NASA's Ames Research Center in Silicon Valley.
This was a huge accomplishment for Virgin Orbit, which is now fully up and running.
"With this successful demonstration in the books, Virgin Orbit will officially transition into commercial service for its next mission. Virgin Orbit has subsequent launches booked by customers ranging from the U.S. Space Force and the U.K.'s Royal Air Force to commercial customers like Swarm Technologies, Italy’s SITAEL and Denmark’s GomSpace," Virgin Orbit representatives wrote in an emailed update after today's flight.
"The company's next few rockets are already well into integration at its Long Beach manufacturing facility," they added.
Virgin Orbit also commemorated the life of Eve Branson, the mother of the company's founder Sir Richard Branson, by flying her name to orbit on the rocket. Eve Branson died this month at age 96 from COVID-19.
Virgin Orbit aims to claim a sizable portion of the growing small-satellite launch market. That market is currently dominated by Rocket Lab, whose Electron booster has been operational since 2018.
But the competition seems poised to start heating up considerably, and not just from Virgin Orbit. For example, California startup Astra's 38-foot-tall (12 meters) Rocket 3.2 reached space for the first time last month, on the company's second orbital test flight. And several other companies, such as Firefly Aerospace and Relativity Space, will start flying their own small-satellite launchers in the near future, if all goes according to plan.
The above vehicles are all designed to give dedicated rides to relatively small spacecraft. That's not the only way for such satellites to fly; they can also hitchhike as secondary payloads on big rockets like SpaceX's workhorse Falcon 9. But such missions are tailored to the big primary payloads, so they generally don't provide as precise a delivery for the small satellites riding piggyback.
Editor's note: This story was updated at 8:30 p.m. EST with more details about the flight from Virgin Orbit.
Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.
The experimental engine is Chinese, but based on American ideas dating back 40 years or more.
Turning sonic booms into combustion addresses a key, "fatal" flaw in scramjet designs.
A Chinese-made "sodramjet" engine has reached nine times the speed of sound in a wind tunnel test. The engine could power an aircraft to reach anywhere in the world within two hours, the makers say.
Scientists say the sodramjet (short for “standing oblique detonation ramjet engine”) could be the first real hope for hypersonic flight—many times the speed of sound, and something that would bring both global travel and space travel much closer to home.
"With reusable trans-atmospheric planes, we can take off horizontally from an airport runway, accelerate into orbit around the Earth, then reenter into the atmosphere, and finally land at an airport," the scientists, from the Chinese Academy of Sciences’ Institute of Mechanics, write in a new study published in the Chinese Journal of Aeronautics. "In this way, space access will become reliable, routine and affordable."
The idea is a decades-old theoretical variation on a scramjet, itself a variation on the ramjet, building on generations of work on high-speed flight.
Many commercial aircraft today have turbofans or, for smaller jets, turboprops. These have descended from the idea of the turbojet, and on the family tree of jet propulsion, the turbojet and ramjet are something like cousins.
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The same way that, say, researchers continue to work on stellarators along with tokamaks and salt-cooled along with lightwater reactors, research on the lower profile idea of the ramjet has continued since the interwar period. Because of their design, turbojets, turbofans, and turboprops work better in the zone we’ve decided is right for passenger flight. For the most part, that’s subsonic flight within Earth’s atmosphere.
The sodramjet is the latest bleeding edge of a completely different use case. The ramjet led to the scramjet, which was designed to go as much as 15 times the speed of sound. Like the fastest combustion and even rocket cars, the secret is in dropping a great deal of weight from the craft—the scramjet scoops up oxygen from the air instead of in condensed form from a tank.
But that means a more fragile cycle of combustion that, it turns out, can be woofed out by the very sonic boom the engine creates. The scramjet just never reached its full potential.
South China Morning Post (SCMP) reports that the sodramjet follows decades of work on scramjets that began in the United States. But in China, development of scramjet concepts has continued, too. Even so, lead researcher Jiang Zonglin grew frustrated with scramjets and decided to go his own way, based on a theory published by NASA in 1980:
“Jiang and colleagues said they were fed up with scramjets’ fatal design weakness. The scramjet could barely generate any thrust at the speed of Mach 7 or beyond. The fuel consumption was so high that no commercial aviation company could possibly foot the bill. And the pilots—not to mention passengers—could suffer heart attacks if they were required to restart the engine from time to time during a flight.”
Concept demonstration model of the sodramjet engine and its installation in a wind tunnel.
ZONGLIN JIANG, ET. AL./CHINESE JOURNAL OF AERONAUTICS
The key difference in the sodramjet is that the new design uses the sonic boom to add combustion, not blow it out.
“Turning the shock wave from their enemy to their friend helped them sustain and stabilise combustion at hypersonic speed,” SCMPreports. “The faster the engine flew, the more efficiently the hydrogen fuel burned. The new engine was also much smaller and lighter than previous models.”
Nothing is certain about this design, which can’t even be tested in a full-speed wind tunnel yet—one simply doesn’t exist. A lot remains to be seen, studied, and proven.
The sodramjet, however, seems to be a hypersonic contender at the beginning of an era where this technology will be critical to travel and exploration.
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L'Égypte dévoile des «trésors» trois fois millénaires
L'Égypte dévoile des «trésors» trois fois millénaires
Les autorités égyptiennes ont dévoilé dimanche au public de nouveaux «trésors» archéologiques découverts dans la nécropole de Saqqarah dont une cinquantaine de sarcophages du Nouvel Empire vieux de plus de 3000 ans.
Ces nouvelles mises au jour ont été effectuées près de la pyramide du roi Téti, premier pharaon de la VIe dynastie de l'Ancien Empire, par une équipe menée par le célèbre égyptologue Zahi Hawass.
«Cette découverte réécrit l'Histoire de Saqqarah et plus particulièrement l'Histoire du Nouvel empire, né il y a 3000 ans», a assuré dimanche à l'AFP M. Hawass, avant d'ajouter que «70% (de cette nouvelle découverte) restent à explorer».
Les sarcophages en bois, datant du Nouvel Empire (XVIe-XIe siècle av. J.-C), ont été retrouvés dans un puits funéraire, selon M. Hawass, qui précise qu'un sarcophage en pierre a également été retrouvé dans un autre puits.
«Nous avons découvert un total de 22 puits funéraires», a-t-il dit à l'AFP. Parmi les découvertes dans ces puits figure celle d'un «soldat à côté duquel reposait sa hache de guerre», a précisé M. Hawass.
En outre, M. Hawass a ajouté que son équipe avait retrouvé «un papyrus d'environ 5m de long contenant le chapitre 17 du livre des morts (...) des masques, des embarcations en bois, des jeux auxquels jouaient les anciens Égyptiens».
L'archéologue estime qu'il s'agit d'une «découverte rare, car la plupart des pièces retrouvées datent du Nouvel Empire. À Saqqarah, c'est plutôt 500 avant J.-C. habituellement».
Plusieurs de ces objets ont été présentés dimanche à la presse, alors que les fouilles se poursuivaient sur le site.
Le ministère des Antiquités et du Tourisme avait révélé dès samedi soir dans un communiqué la teneur de ces découvertes, qu'il avait qualifiées de «majeures».
Le site de Saqqarah, qui se trouve à un peu plus de quinze kilomètres au sud des pyramides du plateau de Gizeh, abrite la nécropole de Memphis, la capitale de l'Égypte ancienne.
Il est classé au patrimoine mondial de l'UNESCO et est connu pour la célèbre pyramide à degrés du pharaon Djéser, la première de l'ère pharaonique.
Ce monument, construit vers 2700 avant J.-C par l'architecte Imhotep, est considéré comme l'un des plus anciens à la surface du globe.
Les autorités espèrent inaugurer en 2021 le «Grand musée égyptien» près du plateau de Gizeh, où se trouvent les célèbres grandes pyramides et le Sphinx.
L'Égypte espère que toutes ces découvertes et son nouveau musée vont redynamiser le tourisme mis à mal par l'instabilité politique et les attentats après la révolution de 2011 qui a chassé Hosni Moubarak du pouvoir, et par la pandémie de COVID-19.
VIDÉOS LIÉES, sélectionnées et publiées par peter2011
The McCallister Case: Alien Close Encounter and a Stolen Artifact
The McCallister Case: Alien Close Encounter and a Stolen Artifact
The Robert McCallister Case has everything, a UFO, a close encounter with the occupant, an alien artifact and a visit from someone who steals the artifact. The case was discovered from Gray Barker a UFO investigator, writer and president of Saucerian Publications a publishing company dedicated to books related to the UFO phenomena.
The incident most probably happened some time in the 60s. Robert McCallister was a boy at the time and on that day during the Christmas holiday season he was in a forest near Salt Lake City (USA) setting up traps to catch coyotes. As he was walking around to check if he had caught something he suddenly confronted a disc-shaped craft hovering about 2 meters above the ground. His first thought was that the object was a hovercraft something he had read about recently in a magazine and therefore was not afraid. The object hovered silently, it had a diameter of about 4.5 meters and featured triangular ports about a meter apart. From behind some rocks a group of strange looking individuals emerged. They were tall and wore helmets similar to those worn by old-time divers. The helmets were attached to a cable.
The same cable was also attached to a type of chair (no details exist of how this chair looked) that was floating in the air at a height of about 3 meters. On the chair sat an old man with white hair and a broad smile. This man did not have a helmet nor wore a uniform similar to the other individuals. Instead he wore a blue tunic and sandals. After a few moments both the old man on the chair and the three individuals floated towards the disc. One of the ports opened and they all entered inside, including the chair. After the port had closed something unexpected happened. The port opened again and the old man appeared; he looked at Robert for a few moments and then approached him. The man took Robert by the hand and started showing him around the discs exterior. Although the man spoke an unknown language, gestures indicated that he was explaining a few things regarding the craft. The man noted the ball-point pen in Robert’s pocket. Robert gave it to him and the man took a piece of paper from his pocket and scribbled on it. When the man handed back the pen Robert insisted that he should keep it as a present. The man accepted the gift with a smile and offered him one of their own pens, he reached out to his pocket and gave it to Robert.
After this exchange of pens the man floated back to the craft´s interior. From the craft’s port the man waved to Robert to move away from the craft most probably to ensure that he maintains a safety distance during take-off. But after a few moments the port opened again and the same man waved at him to move even further away. When he was about 100 meters away Robert turned to look at the craft as it was rising slowly and without any sound. Suddenly, it shot upwards at an incredible speed and disappeared. Once back home he shared his story with his parents and older brother. They laughed at him and did not believe him despite him showing them the pen. The pen was made by a black plastic tube with a glass or plastic point from which ink flowed onto the paper.
Upon his return to school after the Christmas and new-year holidays, Robert shared his story and the “alien artifact” with his teacher and classmates. Although they did not take him seriously he was allowed to pass the pen around for observation by his classmates. A few days later Robert was home alone doing his homework; parents and younger siblings had gone shopping and his older brother was at basketball practice. He heard a knock on the door. There stood a short smiling man trying to communicate through gestures. The man presented a deaf/mute card (item sold outlining the sign-language alphabet). Thinking that the man seeking a contribution Robert offered some coins. The man refused and continued to make gestures; he pointed at the card and then at the “alien-pen” placed on the boy’s shirt pocket as if requesting it to note something down on the card. Robert did not hesitate and gave the pen thinking that the man will write something down that will help their communication. The moment he got hold of the “alien-pen” the short man ran towards the back of the house . Robert heard a car rev-up and then the screech of tires as the car left the scene.
Was this short man part of a government agency dedicated to retrieving alien artifacts and silencing witnesses?
L’affaire Robert McCallister a tout, un OVNI, une rencontre rapprochée avec son occupant, un artefact extraterrestre et une visite de quelqu’un qui vole l’artefact.
Le cas a été découvert par Gray Barker, un enquêteur sur les ovnis, écrivain et président de Saucerian Publications, une société d’édition dédiée aux livres liés aux phénomènes OVNIS. L’incident s’est probablement produit dans les années 60. Robert McCallister était enfant à l’époque et ce jour-là, pendant les vacances de Noël, il se trouvait dans une forêt près de Salt Lake City (USA) en train d’installer des pièges pour attraper les coyotes. Alors qu’il se promenait pour vérifier s’il avait attrapé quelque chose, il a soudainement rencontré un engin en forme de disque, planant à environ 2 mètres au-dessus du sol. Sa première pensée fut que l’objet était un aéroglisseur, quelque chose qu’il avait lu récemment dans un magazine et n’avait donc pas peur. L’objet a plané silencieusement, il avait un diamètre d’environ 4,5 mètres et des orifices triangulaires distants d’environ un mètre. Derrière des rochers, un groupe d’individus étranges émergea. Ils étaient grands et portaient des casques similaires à ceux portés par les plongeurs à l’ancienne. Les casques étaient attachés à un câble.
Le même câble était également attaché à un type de chaise (aucun détail n’existe sur l’apparence de cette chaise) qui flottait dans les airs à une hauteur d’environ 3 mètres. Sur la chaise était assis un vieil homme aux cheveux blancs et au large sourire. Cet homme n’avait pas de casque et ne portait pas d’uniforme semblable aux autres individus. Au lieu de cela, il portait une tunique bleue et des sandales. Après quelques instants, le vieil homme sur la chaise et les trois individus flottèrent vers le disque. L’une des portes s’est ouverte et ils sont tous entrés à l’intérieur, y compris la chaise. Après la fermeture de la porte, quelque chose d’inattendu s’est produit. La porte s’ouvrit de nouveau et le vieil homme apparut; il regarda Robert pendant quelques instants puis s’approcha de lui. L’homme a pris Robert par la main et a commencé à lui montrer l’extérieur des disques. Bien que l’homme parlait une langue inconnue, des gestes indiquaient qu’il expliquait certaines choses concernant l’engin. L’homme a remarqué le stylo à bille dans la poche de Robert. Robert le lui a donné et l’homme a pris un morceau de papier de sa poche et griffonné dessus. Quand l’homme a rendu le stylo, Robert a insisté pour qu’il le garde en cadeau. L’homme a accepté le cadeau avec un sourire et lui a offert un de leurs propres stylos, il a tendu la main à sa poche et l’a donné à Robert. Après cet échange de stylos, l’homme est retourné à l’intérieur de l’engin. Depuis la porte de l’engin, l’homme a fait signe à Robert de s’éloigner de l’engin, probablement pour s’assurer de maintenir une distance de sécurité pendant le décollage. Mais au bout de quelques instants, la porte rouvrit et le même homme lui fit signe de s’éloigner encore plus. Lorsqu’il fut à environ 100 mètres, Robert se tourna pour regarder l’engin qui montait lentement et sans aucun son. Soudainement, il a bondi à une vitesse incroyable et a disparu. De retour à la maison, il a partagé son histoire avec ses parents et son frère aîné. Ils se moquaient de lui et ne le croyaient pas malgré qu’il leur ait montré le stylo. Le stylo était constitué d’un tube en plastique noir avec une pointe en verre ou en plastique à partir de laquelle l’encre coulait sur le papier. À son retour à l’école après les vacances de Noël et du nouvel an, Robert a partagé son histoire et «l’artefact extraterrestre» avec son professeur et ses camarades de classe. Bien qu’ils ne le prennent pas au sérieux, il a été autorisé à faire circuler le stylo pour l’observation de ses camarades de classe. Quelques jours plus tard, Robert était seul à la maison pour faire ses devoirs; les parents et les frères et sœurs plus jeunes étaient allés faire du shopping et son frère aîné était à l’entraînement de basket-ball. Il entendit un coup à la porte. Il y avait un petit homme souriant essayant de communiquer par des gestes. L’homme a présenté une carte sourd / muet (article vendu décrivant l’alphabet en langue des signes). Pensant que l’homme cherchait une contribution, Robert a offert des pièces de monnaie. L’homme a refusé et a continué à faire des gestes; il montra la carte puis le «stylo extraterrestre» placé sur la poche de la chemise du garçon comme s’il lui demandait de noter quelque chose sur la carte. Robert n’a pas hésité et a donné le stylo en pensant que l’homme écrirait quelque chose qui faciliterait leur communication. Au moment où il attrapa le «stylo extraterrestre», le petit homme courut vers l’arrière de la maison. Robert a entendu une voiture accélérer puis le crissement des pneus alors que la voiture quittait les lieux.
Ce petit homme faisait-il partie d’une agence gouvernementale dédiée à la récupération d’artefacts extraterrestres et à la réduction au silence des témoins ?
La sonde New Horizons continue son exploration de la ceinture de Kuiper.
Le 19 janvier 2006, une fusée Atlas-V propulsait la sonde New Horizons dans l'espace en direction de Pluton et de la ceinture de Kuiper. Elle vogua d'abord vers la planète Jupiter qu'elle a survolée le 28 février 2007 à une distance de 23 millions de kilomètres. La manœuvre lui a permis de bénéficier de l'assistance gravitationnelle de la géante gazeuse et de prendre la route de Pluton.
A la découverte de la Ceinture de Kuiper
La ceinture de Kuiper est une vaste zone en forme d'anneau composée d'une myriade de petits corps et de plusieurs planètes naines dont Pluton. Elle est située au-delà de l'orbite de Neptune entre 30 et 55 unités astronomiques. Gigantesque et quasi inexplorée, cette partie du Système solaire recèle pourtant bien des secrets : c'est un réservoir de comètes périodiques qui abrite des astres probablement contemporains des débuts du Système solaire, tandis que d'autres ont pu s'y former puis migrer secondairement et se rapprocher du Soleil. C'est sans doute le cas de Cérès et de Triton (une lune de Neptune). Avec 2.372 km de diamètre, Pluton est le plus gros membre de cette ceinture de Kuiper mais pas le plus massif puisque Eris, découverte en 2005, la dépasse. C'est notamment à cause de cette dernière que Pluton a été déchue de son statut de planète pour devenir une planète naine selon la définition adoptée par l'Union astronomique internationale le 24 août 2006, soit à peine 8 mois après le lancement de New Horizons.
Des milliers d'images et de mesure de Pluton
Si cette nouvelle définition n'a pas fait que des heureux (surtout de l'autre côté de l'Atlantique), elle n'altère en rien l'intérêt et les résultats qu'obtiendra la sonde. Après des années d'hibernation, elle sera réveillée quelques mois avant d'atteindre son premier but. Et le 14 juillet, après un voyage de près de 6,5 milliards de kilomètres, l'engin survolera la planète désormais naine à seulement 11.000 km de sa surface. De ce passage historique, il restera des milliers d'images et de mesure qui révèlent la complexité de ce monde recouvert de glace sous laquelle réside peut-être un océan liquide comme sur son satellite Charon.
New Horizons
La sonde New Horizons est dans l'espace depuis 15 ans.
Jupiter
Première planète photographiée par la sonde New Horizons.
Io
La surface de Io, survolée ici le 28 juin 2007 par la sonde New Horizons. On y aperçoit une éruption volcanique au sommet.
Europe
Europe est l'un des quatre plus gros satellites de la planète Jupiter. Cette vue est celle d'un lever d'Europe au-dessus de Jupiter.
Etoiles
Une des photos de l'espace lointain prise par la sonde New Horizons.
Pluton
New Horizons a réalisé un survol historique de la planète naine Pluton le 14 juillet 2015.
Surface de Pluton
De nombreuses images de la surface de Pluton continuent d'être analysées par les scientifiques.
Le cœur de Pluton
Le cœur de Pluton ou la région Tombaugh est une vaste plaine glacée de 2000 km de large.
Montagnes dans le cœur de Pluton
Rangée de montagnes dans le "coeur" de Pluton : une image de l'instrument Lorri de New Horizons.
"Dark side" de Pluton
Quelques minutes après son survol, New Horizons a photographié la face cachée de Pluton.
Macule Cthulhu
La région de Cthulhu sur Pluton héberge de hautes montagnes dont le sommet est couvert de glace de méthane.
Charon
Cette image de Charon a été prise le 13 juillet 2015, c'est-à-dire 24 heures avant le survol au-dessus de Pluton.
Nyx et Hydra
Nyx et Hydra sont deux petites lunes qui orbitent autour de Pluton.
Arrokoth
L'astéroïde Arrokoth a été visité par la sonde le 1er janvier 2019.
Disque de poussière du système solaire
L'instrument Student Dust Counter (SDC) mesure la taille et la distribution des particules de poussières se trouvant sur la trajectoire de New Horizons et dont la masse est comprise entre 10−12 et 10−9 g.
VIDÉOS LIÉES, sélectionnées et publiées par peter2011
Hot on the heels of successfully snagging hunks of space rock in October, the scientists behind NASA's OSIRIS-REx asteroid sample-return mission are contemplating sending the spacecraft to study a second asteroid in 2029, this time the infamous Apophis.
If that appointment comes to be, the spacecraft will arrive at Apophis in April 2029, just over a week after the asteroid makes a hair-raisingly close approach to Earth, within about 19,800 miles (31,900 kilometers) of our planet's surface. Scientists are confident that the asteroid won't impact Earth, but Apophis still has quite a reputation for a space rock, and discovering OSIRIS-REx could visit it provided an unexpected opportunity for the mission.
"Definitely it was a surprise, a very good surprise," Dante Lauretta, a planetary scientist at the University of Arizona and the principal investigator for OSIRIS-REx, told Space.com of the moment in October 2019, when a team member reported that the spacecraft could make a long stay at Apophis.
"I thought for sure extended-mission targets were going to be flyby kind of opportunities, more traditional," Lauretta said. "Those are pretty easy to design in the inner solar system. But when [the OSIRIS-REx mission designer] came back and said we could put the spacecraft into orbit around a second large near-Earth asteroid, I was really excited."
But of course, the priority for the OSIRIS-REx team has been the primary mission of the spacecraft (formally dubbed the Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer): collect and deliver a sample from the asteroid Bennu for scientists to analyze in their laboratories on Earth.
That task is going smoothly: OSIRIS-REx collected its space rock on Oct. 20 and will leave Bennu for the long journey home sometime this spring, arriving in September 2023. And just like the Japanese Hayabusa2 asteroid-sampling mission, which returned its samples from an asteroid called Ryugu in December, only a small capsule will actually return to Earth, jettisoned by the main spacecraft, which will then be free to explore other destinations — assuming, of course, the paperwork comes through.
The OSIRIS-REx team plans to propose an extended mission to NASA in the summer of 2022, Lauretta said. Visiting Apophis is one option for what that extended mission could look like, but so far, it's the only target that engineers have found the spacecraft could visit long-term. And a flyby might not do the spacecraft justice in terms of its capabilities and current condition, which Lauretta said is "excellent."
"We don't have a solution that gets us to rendezvous with another asteroid at all right now," Lauretta said. "It really is the unique nature of the Apophis close approach to the Earth in 2029 that even enables us to do this."
A depiction of Apophis flying past the ring of satellites surrounding Earth in April 2029. (Image credit: Marina Brozović/JPL)
Same spacecraft, new asteroid, new science
OSIRIS-REx has lost only one mode of one instrument; otherwise, everything is in working order, Lauretta said.
In fact, a second asteroid visit would give scientists the opportunity to use an instrument that never actually studied Bennu: OSIRIS-REx was equipped with two lasers for the spacecraft to shoot off the rock and study the echo to facilitate its landing and sampling maneuver. But when the spacecraft arrived, mission personnel learned the asteroid was far too rocky for the system to work and devised an alternative navigation system.
Most lasers don't last long in space, so having two working lasers on a spacecraft older than a decade is rare, Lauretta said. "Having two fresh lasers that we've never used, I'm actually kind of excited about that," he said. "Especially because we built the hardware and we never got to use it. I just feel bad for the instrument. Like, aww, you got all the way to Bennu and all you got to do is get checked out and then we turned you off and you never got to see any action."
In general, an observation campaign at Apophis would likely look quite similar to what the spacecraft did at Bennu.
First, there's a long chain of approach observations, starting with the asteroid seen as just a speck of light, slowly growing into a whole new world. That sequence would begin perhaps around April 8, 2029. OSIRIS-REx won't have a front-row seat to Apophis' close approach, which will occur on April 13.
But seeing the aftermath of the encounter could more than make up for the late arrival, Lauretta said. Scientists expect the brush with Earth's gravity to affect Apophis itself — its precise location, spin and even the space rock's surface and interior structure. The spacecraft would be able to look for signs of what took place during the close approach. "We're really interested in the effect that passing deep into theEarth's gravity fieldhas on the asteroid properties," Lauretta said.
Particularly prominent might be a change in how the asteroid spins. A second possibility the spacecraft could explore is that the close approach would sculpt the space rock's surface as Earth's gravity tugs at Apophis
"It could trigger mass movement on the surface, and we would definitely be looking for that," Lauretta said. "Even though we might not see the motion due to the gravitational interaction with the Earth, we could see evidence that things had moved recently: freshly exposed surfaces, maybe even a population of particles that were kicked up, that are in orbit around Apophis."
But Lauretta isn't convinced that the drama of the asteroid's flyby is necessary to justify sending OSIRIS-REx on to Apophis once its precious cargo is delivered. Bennu and Apophis belong to different asteroid families with similar structures, and OSIRIS-REx was designed to create incredibly detailed portraits of large space rocks.
"In order to get as much science out of this vehicle as possible, it would be great to go to a different asteroid with a different composition, and collect the same kind of high-fidelity data that we had to generalize our understanding of the physical environment of asteroid surfaces as we've learned from the OSIRIS-REx mission," Lauretta said.
Sending OSIRIS-REx to visit a second asteroid could also help solve perhaps the biggest mystery the spacecraft discovered at Bennu: streams of particles shooting off the rock into space. "Those surprised us so much at Bennu," Lauretta said. "That's a day that I'll never forget, when I saw that first image of what looked like an eruption from the asteroid. And we don't know what's causing those."
The ejections could depend on Bennu's water-rich composition, or they might be a more common trait. As an asteroid of similar size and structure but very different stony material, Apophis could settle that question. "One of the hypotheses is that this is due to micrometeoroids impacting the asteroid," Lauretta said. "If that's the case, Apophis should have just as many particles as Bennu."
And then there's that ineffable quality that Apophis carries with it, from its discovery in 2004, when scientists' measurement of its orbit was uncertain enough that in some scenarios, its 2029 flyby went very, very badly indeed, with the asteroid slamming into Earth. Additional observations cleared up the concern, but it's a difficult reputation to shake for an asteroid named after a mythological Egyptian serpent of chaos.
"It really does enable some unique science," Lauretta said. "Quite honestly, any large asteroid that popped up as a rendezvous target would be super exciting for us. The fact that it was Apophis! Apophis is just famous, so everybody knows exactly what I'm saying when I tell them the asteroid that we want to target."
Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow uson Twitter @Spacedotcom and on Facebook.
Astronomers have discovered black widows and redbacks in space. While these cosmic objects don't kill and eat their mates, the stars share their eight-legged counterparts' violent behavior toward companions.
In addition to the run-of-the-mill spider stars, the researchers also discovered a bizarre black widow-redback crossbreed. The scientists used the now-destroyed Arecibo telescope in Puerto Rico to discover the weirdo stars.
Spider stars are types of millisecond pulsars, or neutron stars that act like precise clocks in the sky, whirling around at least once every 30 milliseconds and flashing like a lighthouse with each rotation. Neutron stars, the tiny, compressed cores of old, exploded stars, often rip material from other stars locked in binary orbits with them and use the push of that infalling material to get up to pulsar speed. Spider stars are rare and special versions of these stars though: They orbit so close to their binary companions that they blast away their surfaces, inhaling vast amounts of material like a spider tearing its partner limb from limb.
In a new paper, researchers identify three new black widows and a redback in the Milky Way. They also found a spider star that defies categorization, almost like a crossbreed of the two species.
When a spider star has reduced its companion to significantly less than a tenth the mass of the sun (usually 0.02 to 0.03 times the sun's mass), that star is called a black widow. Redbacks have heftier companions that boast more than a tenth of the sun's mass. These binary companions of redbacks pass between the spider star and Earth periodically, creating temporary eclipses. The shriveled companions of black widows don't typically pull off that trick.
The seeming crossbreed star is difficult to categorize. For now, researchers have labeled it a redback because its companion sometimes eclipses its ticking light. And that companion has a mass at least 0.055 times the mass of the sun (possibly larger), which would be quite heavy for a black widow, though quite light for a redback. For now, the exact mechanisms of that system are still a mystery.
Studies like this might get harder in the future. The paper, published Jan. 1 to the arXiv database, relied on data collected between 2013 and 2018 using the Arecibo 305-m radio telescope which has since collapsed, as Live Science reported.
The haze shrouding Plutomight be made up of ice crystals possessing cyanide hearts, a new study finds.
Hazes, which are made of tiny motes of dust, smoke, ice and other substances, are not unique to Earth — scientists have detected hazes enveloping Mars, Venus, Saturn and Jupiter.
Nor are hazes limited to planets. Saturn's largest moon Titan, the only moon known to have clouds, is cloaked in a thick orange haze similar in makeup to smog on Earth. NASA's Voyager 2 spacecraft also detected haze in the atmosphere of Neptune's largest moon Triton.
NASA's New Horizons mission, which flew by Pluto in 2015, unexpectedly revealed Pluto also possesses haze hugging the dwarf planet's frozen surface. Since Pluto, Titan and Triton are all icy worlds with atmospheres rich in nitrogen, methane and carbon monoxide, researchers had thought they might all possess similar kinds of hazes.
Previous research found Titan's haze was the result of solar ultraviolet rays triggering chemical reactions in the icy moon's upper atmosphere. These created simple organic compounds that went on to help form ever larger and more complex organic molecules.
However, scientists now find the hazes on Pluto and Triton might have significantly different origins than Titan's.
NASA's Voyager 2 spacecraft captured dark streaks produced by geysers visible on the icy surface of Triton's south polar region. (Image credit: NASA/JPL)
"Although Titan and Pluto seem very similar, their haze properties can be drastically different," study lead author, Panayotis Lavvas, a planetary scientist at the University of Reims Champagne-Ardenne in Reims, France, told Space.com.
When the researchers analyzed computer models of haze formation, they discovered that if the same chemical reactions at work on Titan happened on Pluto, they could only create about half the haze particles that prior work detected on the dwarf planet. (Since Pluto's atmosphere is roughly 175 degrees Fahrenheit, or 80 degrees Celsius, colder than Titan's, its atmospheric chemistry runs slower.)
In the new study, Lavvas and his colleagues suggest that as on Titan, sunlight triggers chemical reactions in Pluto's upper atmosphere, forming simple compounds such as hydrogen cyanide, a molecule made up of one hydrogen, one carbon and one nitrogen atom. Their models suggested hydrogen cyanide might freeze to produce tiny ice particles.
NASA's Cassini spacecraft looks toward the night side of Saturn's largest moon and sees sunlight scattering through the periphery of Titan's atmosphere and forming a ring of color. (Image credit: NASA/JPL-Caltech/Space Science Institute)
As these microscopic ice particles settle downward due to gravity, other gases condense around these seeds to coat them. As such, haze particles on Pluto may be largely made of a variety of ices, instead of more complex organic compounds as on Titan. The sizes, amounts and atmospheric distributions of these ice grains in the computer models closely match those of the haze particles detected on Pluto, the scientists noted.
In addition, these ice particles on Pluto should interact less with incoming solar energy than haze particles on Titan, the researchers said. As such, they should play a smaller role in controlling heat in Pluto's atmosphere than previously thought, Lavvas said.
When it comes to Triton, since it possesses an even colder atmosphere than Pluto's, the scientists noted its hazes should prove even icier.
"This comparison of Titan, Pluto and Triton illuminates the important differences in the mechanisms of haze formation in planetary atmospheres," Lavvas said.
The scientists detailed their findings online Dec. 21 in the journal Nature Astronomy.
Follow Charles Q. Choi on Twitter @cqchoi. Follow us on Twitter @Spacedotcom and on Facebook.
The surface features of brown dwarfs – objects midway in mass between planets and stars – can’t be seen. But researchers have found a way to reveal Jupiter-like stripes and bands in the atmosphere of the closest brown dwarf, Luhman 16B.
Recently, we showed you a cool new direct image taken of a brown dwarf, an object midway in mass between a planet and a star. But that image doesn’t show the brown dwarf’s surface features. No existing image does. These objects are too far away – and too dim – to reveal themselves in that way. Now, though, a brown dwarf’s surface appearance has been revealed by researchers. The new study indicates bands and stripes in the atmosphere of Luhman 16B – one of two objects in the Luhman 16 binary brown dwarf system – the closest known brown dwarfs to Earth at only 6.5 light-years. Scientists said their new technique for revealing the stripes and bands on Luhman 16B will also be useful someday in mapping surface features on Earth-like planets in distant solar systems. Now that would be something to see!
In our solar system, the gas giant planets Jupiter and Saturn both sport stripes and bands. Scientists had wondered if brown dwarfs had any such stripes. Or would their atmospheres appear more chaotic? Based on the study of Luhman 16B, they believe that at least some brown dwarfs do have banded atmospheres.
We wondered, do brown dwarfs look like Jupiter, with its regular belts and bands shaped by large, parallel, longitudinal jets? Or will they be dominated by an ever-changing pattern of gigantic storms known as vortices like those found on Jupiter’s poles?
The researchers published the peer-reviewed study in The Astrophysical Journal on January 7, 2021.
The results provide a new glimpse of these mysterious worlds that are too massive to be considered planets, but not massive enough to ignite their nuclear fuel to become stars. And while it seems that brown dwarfs might look a lot like gas giant planets, at least in some cases, they’re still not planets. They are their own unique cosmic objects.
View larger. | WISE image of the brown dwarf binary system Luhman 16, closest known brown dwarfs to Earth at just over 6 light-years. This is the 3rd-closest-known system to our sun (after the Alpha Centauri system and Barnard’s Star). In the inset, the system is resolved into a pair. But no surface features are revealed for this brown dwarf system, or any other.
Image via NASA Wide-field Infrared Survey Explorer (WISE).
Apai and his colleagues determined that Luhman 16B looks a lot like Jupiter. High-speed winds flow parallel to its equator, just like wind patterns on the gas giant. These winds help mix the atmosphere and redistribute heat that originates from deeper down. The researchers also found that there are vortex-type storms at the brown dwarf’s poles, also similar to what we see on Jupiter. While scientists didn’t know exactly what the atmospheres of brown dwarfs would look like, for the most part, some computer models had predicted an appearance quite similar to what was seen on Luhman 16B. Apai said:
Wind patterns and large-scale atmospheric circulation often have profound effects on planetary atmospheres, from Earth’s climate to Jupiter’s appearance, and now we know that such large-scale atmospheric jets also shape brown dwarf atmospheres.
Knowing how the winds blow and redistribute heat in one of the best-studied and closest brown dwarfs helps us to understand the climates, temperature extremes and evolution of brown dwarfs in general.
This is a section of Jupiter’s atmosphere. Jupiter – the biggest planet in our solar system – is dominated by global winds, giving it a banded appearance. But Jupiter also has localized vortices, vast storms, at its poles. Researchers have long wanted to know if brown dwarfs – objects midway in mass between Jupiter and a star – looked like Jupiter, with a striped or banded atmosphere. Or would brown dwarfs look more like our sun, with a chaotic atmosphere? See the image below.
Like Jupiter, the atmosphere of Luhman 16B appears to be dominated by global winds. In other words, this brown dwarf has stripes and bands in its atmosphere, like Jupiter. This image is a video still from the video at top. Watch that video to see all the amazing details in the atmosphere of Luhman 16B, derived via data analysis by the University of Arizona scientists.
Brown dwarf surfaces can’t be seen directly. They’re too dim, and too far away, to reveal themselves in that way. So how did Apai and his team figure out what Luhman 16B looks like?
They used newly-developed algorithms designed for NASA’s Transiting Exoplanet Survey Satellite (TESS) to measure the brightness patterns of the two closest known brown dwarfs, Luhman 16A and Luhman 16B, only 6.5 light-years from Earth, and both about the size of Jupiter (but much more massive than Jupiter). Luhman 16A is approximately 34 times Jupiter’s mass, and Luhman 16B is about 28 times Jupiter’s mass. Luhman 16B is also about 1,500 degrees Fahrenheit (830 degrees Celsius) hotter than our sun (but still not hot enough to be a star). As Apai explained:
The TESS space telescope, although designed to hunt for extrasolar planets, also provided this incredibly rich and exciting dataset on the closest brown dwarf to us. With advanced algorithms developed by members of our team, we were able to obtain very precise measurements of the brightness changes as the two brown dwarfs rotated. The brown dwarfs get brighter whenever brighter atmospheric regions turn into the visible hemisphere and darker when these rotate out of view.
Daniel Apai, Associate Professor of Astronomy and Planetary Sciences at the University of Arizona, who led the new study.
Even though TESS, or any other existing telescope, can’t see brown dwarfs in detail, the brightness of the brown dwarfs can be measured, which provides clues as to their appearance. Apai said:
No telescope is large enough to provide detailed images of [exo-]planets or brown dwarfs. But by measuring how the brightness of these rotating objects changes over time, it is possible to create crude maps of their atmospheres, a technique that, in the future, could also be used to map Earth-like planets in other solar systems that might otherwise be hard to see.
And that’s exciting, isn’t it?
In the case of Luhman 16B, the researchers were able to collect data from multiple rotations of the brown dwarf. This, and also the fact that TESS isn’t hindered by daylight, allowed the scientists to obtain the most detailed view of a brown dwarf’s atmosphere to date.
It’s a preliminary, but fascinating, look at these bizarre objects. This new method will allow astronomers to observe in more detail the atmospheres of other brown dwarfs as well as gas giant exoplanets, according to Apai:
Our study provides a template for future studies of similar objects on how to explore – and even map – the atmospheres of brown dwarfs and giant extrasolar planets without the need for telescopes powerful enough to resolve them visually.
Brown dwarfs are unique objects, too massive to be considered planets, but not massive enough to become stars. Most are about the size of Jupiter, but much more massive.
Being able to “see” these worlds in this way will help astronomers better understand how both brown dwarfs and gas giant exoplanets form and evolve. That data will also show in what ways these objects are similar, and how they are different. As we’ve seen with Luhman 16B, they may appear quite similar on the outside with their banded atmospheres, but what about deeper down? Are their compositions similar or significantly different?
In May 2020, astronomers using the Very Large Telescope in Chile found that Luhman 16B’s companion, Luhman 16A, also has a banded atmosphere, although with fewer but broader stripes. At the time, it was thought that Luhman 16B had patchy clouds, but now the new study shows it is banded as well, and likely has more bands than Luhman 16A, making it look even more like Jupiter than its companion.
Bottom line:New observations of the closest known brown dwarf show that it looks a lot like Jupiter, with bands of powerful jet streams in its atmosphere.
Far-off in the Milky Way galaxy, 21,000 light-years from Earth, astronomers have spotted the fastest-spinning magnetar (and possibly youngest, too) ever seen. And that's just the start of what makes this star strange.
Magnetars are a unique type of neutron stars, which are the collapsed cores of supergiant stars that died in supernova events. What sets magnetars apart from other neutron stars is that they possess extremely powerful magnetic fields — he most powerful ones in the known universe, in fact. They can also explode without warning and are fairly difficult to spot. In fact, before this object was discovered, there were only 30 known magnetars, compared to the thousands (approximately 3,000) known neutron stars.
Now, scientists studying the skies with NASA's Chandra X-ray Observatory — a space telescope that looks out at black holes, supernovas and more — think that a newly discovered magnetar known as J1818.0-1607 could be the fastest-spinning and possibly also the youngest magnetar known, according to a statement. They also found a myriad of other odd things that make this object truly unique.
Magnetar J1818.0-1607, which lies 21,000 light-years away from Earth in the Milky Way galaxy. (Image credit: Credit: X-ray: NASA/CXC/Univ. of West Virginia/H. Blumer; Infrared (Spitzer and Wise): NASA/JPL-CalTech/Spitzer)
Astronomers first spotted this magnetar on March 12, 2020 with NASA's Neil Gehrels Swift Telescope. Later on, Harsha Blumer, an astronomer at West Virginia University, and Samar Safi-Harb, a physics professor at the University of Manitoba in Canada, observed the magnetar using Chandra, and they noticed a couple of peculiar things that made the magnetar stand out.
One of the first things that seemed intriguing about this particular object was how young it appeared. The team estimated that the magnetar is about 500 years old, which, if true, would make it the youngest discovered yet. They determined the object's age by measuring how quickly the rotation rate of the magnetar is slowing down (it spins slower over time) while assuming that the object started out spinning much faster.
The second thing that really stood out to the team was just how fast the object was spinning, as it seemed to be rotating once fully every 1.4 seconds (which is really, really fast).
Other astronomers have taken a look at J1818.0-1607 as well, observing the magnetar using radio telescopes like the National Science Foundation's Karl Jansky Very Large Array (VLA) and have found that it's emitting radio waves, a quality it shares with objects known as "rotation powered pulsars." These are a type of neutron star that emits radiation that we on Earth detect as "pulses" of radio wave emissions.
In this up-close composite image, you can see magnetar J1818.0-1607 in purple. Scientists think that this object could be the fastest-spinning and possibly even youngest magnetar ever found. (Image credit: X-ray: NASA/CXC/Univ. of West Virginia/H. Blumer; Infrared (Spitzer and Wise): NASA/JPL-CalTech/Spitzer)
Blumer and Safi-Harb also found that the magnetar isn't converting spinning energy from its rotations into X-ray emissions as efficiently as expected for a magnetar. In fact, the object is converting this energy at a rate most common with rotation-powered pulsars, another interesting commonality between the two objects.
The last odd thing that the pair of researchers found about this young, fast star was that, while most magnetars around this age would have left behind a debris field of material leftover from the supernova that created the object, the researchers only found possible evidence of a supernova remnant with J1818.0-1607, and this debris was pretty far from the object.
By their estimations, in order for the debris field to have traveled that far away from the magnetar, the object would've needed to have traveled at speeds faster than ever seen with a neutron star.
New work agrees with older research suggesting the oldest light in the universe – from the most distant galaxy yet known – started its journey toward us 13.77 billion years ago.
View larger. | In 2013, the Planck space telescope released the most detailed map to date of the cosmic microwave background, the relic radiation from the Big Bang. It was the mission’s first all-sky picture of the oldest light in our universe, imprinted on the sky when it was just 380,000 years old. Now a new, independent study agrees with Planck’s results. That’s good news for astronomers trying to pin down the universe’s age and rate of expansion.
How old is our universe? That’s one of humanity’s oldest and most fundamental questions. Now, astronomers using the Atacama Cosmology Telescope (ACT), high in the Andes of northern Chile, have announced a new measurement of the cosmic background radiation, our universe’s oldest light, discovered in 1965 and sometimes called an echo of the Big Bang. The new measurement suggests the universe is 13.77 billion years old, give or take 40 million years. This new result agrees strongly with results from the European Space Agency’s Planck satellite, which measured the cosmic background radiation from 2009 to 2013. And it agrees with what’s called the Standard Model of particle physics, developed in the 1970s and refined in the years since then. The Standard Model encapsulates scientists’ best current understanding of how elementary particles and the fundamental forces of nature relate to one another.
The new peer-reviewed results were published in the Journal of Cosmology and Astroparticle Physics on December 30, 2020.
Agreement between independent studies gives scientists confidence their work is correct. Non-agreement does the opposite: it makes scientists think their ideas need more work. In 2019, a study had suggested the age of the universe might be hundreds of millions of years younger than Planck’s data had indicated. The new results from the Atacama Cosmology Telescope, on the other hand, agree with Planck’s results. Simone Aiola of the Flatiron Institute’s Center for Computational Astrophysics – a co-author on the new study – commented:
Now we’ve come up with an answer where Planck and ACT agree. It speaks to the fact that these difficult measurements are reliable.
Like the Planck satellite, the Atacama Cosmology Telescope (ACT) in Chile also studies the cosmic microwave background. Here’s a portion of a new ACT image, covering a section of the sky 50 times the width of a full moon. This image represents a region of space 20 billion light-years across.
The new measurements don’t just tell us the age of the universe. They also suggest how fast the universe is expanding.
The rate at which the universe is expanding is described by what’s called the Hubble Constant. Writing at his blog on January 6, 2021, astrophysicist Brian Koberlein described the Hubble Constant in the context of the cosmic microwave background in this way:
In the early universe, there were small fluctuations of density and temperature within the hot dense sea of the Big Bang. As the universe expanded, the fluctuations expanded as well. So the scale of fluctuations we see in the cosmic microwave background today tells us how much the universe has grown. On average, the fluctuations are about a billion light-years across, and this gives us a value for the rate (the Hubble parameter) as somewhere between 67.2 and 68.1 kilometers per second per megaparsec.
The new data from ACT gives a Hubble constant of 67.6 kilometers per second per megaparsec. The Planck researchers had previously estimated 67.4 km per second per megaparsec. Steve Choi at Cornell University, first author of the new paper, said:
I didn’t have a particular preference for any specific value; it was going to be interesting one way or another. We find an expansion rate that is right on the estimate by the Planck satellite team. This gives us more confidence in measurements of the universe’s oldest light.
Steve Choi at Cornell University, lead author of the new study.
It’s worth noting, however, that – though the values for the Hubble Constant derived from data by Planck and ACT agree well – neither agrees well with values for the Hubble Constant derived via distant variable stars and supernovae (exploding stars). Brian Koberlein explained:
… you can use variable stars and distant supernovae to create a cosmic distance ladder that tells you the rate of expansion. The problem is, this alternative method gives a larger value for the Hubble parameter. If the supernova method is right, then the universe is younger and has expanded more quickly than the [work on the cosmic background radiation] seems to support. For a while, the hope has been that new observations and new methods of measuring cosmic expansion would solve this problem …
But, Koberlein said, the new study from ACT dashes those hopes.
The growing tension between these distant versus local measurements of the Hubble Constant suggests that we may be on the verge of a new discovery in cosmology that could change our understanding of how the universe works. It also highlights the importance of improving our measurements of the cosmic microwave background with the Atacama Cosmology Telescope as well as the future Simons Observatory and CCAT-prime projects that we are now building.
The universe is ancient, but how ancient? The current answer appears to be 13.77 billion years, give or take 40 million years.
To calculate the universe’s age, scientists need to estimate how far light from the cosmic microwave background (CMB) – the “afterglow” of the Big Bang and the measurable record of when photons first escaped the “fog” of the early universe – has traveled to reach Earth. But that is not an easy task, so astronomers use triangulation by measuring the angle in the sky between two distant objects. With Earth as the third point of the triangle, they can then estimate the distance of both objects from Earth.
ACT is able to measure slight fluctuations in the cosmic microwave background with great precision, which helps to refine the estimates. Suzanne Staggs at Princeton University commented:
The Planck satellite measured the same light, but by measuring its polarization in higher fidelity, the new picture from the Atacama Cosmology Telescope reveals more of the oldest patterns we’ve ever seen.
Bottom line: New observations of the oldest light in the universe indicate that the cosmos is 13.77 billion years old, and help resolve inconsistencies with other previous estimates.
The Red Planet is wiggling and wobbling as it spins, research in the journalGeophysical Research Letters confirms, and astronomers have no idea why.
Like a toy top that teeters as it loses speed, the poles ofMars are wandering ever-so-slightly away from the planet's axis of rotation, moving about 4 inches (10 centimeters) off-center every 200 days or so, researchers reported in a study published Oct. 13, 2020. That makes Mars only the second known planet in the universe to exhibit this phenomenon — known asthe Chandler wobble — with Earth being the first, according to the American Geophysical Union's (AGU) news blog,Eos.org.
This wobble — named for astronomer Seth Carlo Chandler, who discovered the phenomenon more than a century ago — is an effect seen in planets that aren't perfectly round, science writer Jack Lee wrote at Eos. OnEarth, the wobble is much more pronounced: Our planet's poles wander roughly 30 feet (9 m) from its axis of rotation, wobbling in a circular pattern that repeats every 433 days or so.
This wonky wobble has negligible effect on our planet, according to Eos, but still presents a puzzle. Scientists have calculated that the wobble should naturally die down within a century of its origin, but our planet's current wobble has been going strong for much longer than that. Something — perhaps a combination of pressure changes in the atmosphere and oceans, one2001 study proposed — seems to be perpetually reigniting the wobble, though the exact mechanism is still unknown.
The Mars wobble is just as puzzling. The authors of the new study detected the wobble using 18 years of data collected by three satellites orbiting the Red Planet: Mars Odyssey, Mars Reconnaissance Orbiter and Mars Global Surveyor. This small shift in the Martian poles should also resolve itself naturally, the team calculated, but currently appears to be going strong.
Devoid of oceans, Mars and its wobbly rotation may be governed by atmospheric pressure changes alone, according to Eos, but further study of our tipsy neighbor is required to know for sure.
High above the North Pole, the polar vortex, a fast-spinning whirl of frigid air, is doing a weird shimmy that may soon bring cold and snowy weather to the Eastern U.S., Northern Europe and East Asia for weeks on end, meteorologists say.
While it's not unusual for the polar vortex to act up, this particular reconfiguration — wandering around and possibly splitting in two — may be tied to climate change in the rapidly warming Arctic, said Judah Cohen, director of seasonal forecasting at Atmospheric and Environmental Research in Massachusetts, part of Verisk Analytics, a risk-assessment company.
"Expect a more wintery back-half of winter here in the Eastern U.S. than what we had in the first half," Cohen told Live Science.
The warmer-than-usual temperatures in the Arctic are likely throwing the polar vortex out of whack, Cohen said. The polar vortex is a vast area of low pressure that sits high above the Arctic in the stratosphere — the layer above the troposphere, the lowest layer of Earth's atmosphere where most weather conditions happen. This low-pressure system is usually filled with cold, swirling air. During the winter, a jet stream of air that keeps the polar vortex in place sometimes weakens, allowing the vortex's chilly air to extend southward.
Here's an animated video Cohen made illustrating the process.
Cohen and colleagues have suggested that less Arctic sea-ice cover means there's more moisture from the sea migrating inland over normally dry Siberia. This moisture then turns into snow, which reflects heat back into space and is making Siberia colder than normal; that in turn disrupts a thermal band in the troposphere extending over Eurasia. This discombobulated band can then destabilize the polar vortex, causing colder winters east of the Rockies in the U.S. and in Northern Europe and East Asia, Cohen and his colleagues wrote in a 2019 review in the journal Nature Climate Change.
"Think of the polar vortex like a quiet, fast spinning top that spins in place," Cohen said. "Then, you have this energy [from the troposphere] that starts banging" on the spinning polar vortex, making it wobble and wander.
He added that this season, "snowfall across Siberia has been above normal so far. Therefore, I do believe it has contributed to the weak polar vortex."
(Image credit: NOAA)
Not everyone agrees with this increased-Siberian-snow-and-wobbly-polar-vortex connection, but it is clear that a weakened polar vortex leads to colder winters in certain parts of the Northern Hemisphere. It's also accepted that so-called sudden stratospheric warming (SSW) events can weaken the polar vortex and make it teeter around. SSWs happen when large-scale atmospheric waves associated with weather systems reach into the stratosphere and disrupt the polar vortex, causing it to slow down and heat up as much as 90 degrees Fahrenheit (50 degrees Celsius) within a few days.
Cohen noted that SSWs can be triggered by weather conditions associated with the Arctic's disappearing sea ice. SSWs happen an average of six times every 10 years, and right now we're experiencing a big SSW, The Washington Post reported.
It's possible the SSW was caused by a high-pressure, low-pressure system, said Amy Butler, a research scientist at the National Oceanic and Atmospheric Administration Chemical Sciences Laboratory in Boulder, Colorado.
"Over the last few weeks, there was a persistent high-pressure system over much of the North Atlantic and northern Europe/Asia, and a low-pressure system over the North Pacific," Butler told Live Science in an email. This high-pressure, low-pressure duo is known to disrupt the stratosphere, where the polar vortex lives.
It's also possible that the extreme bomb cyclone (a rapidly-forming winter storm with hurricane-strength winds) in the North Pacific a few days ago, contributed to the SSW, "but that will have to be investigated further," she said.
On Jan. 5, the polar vortex's counter-clockwise winds reversed direction (a clue that a sudden atmospheric warming event had happened) and the vortex wandered from its usual location centered over the North Pole, toward Europe and the North Atlantic, Butler said. During that time, it began to (but didn't completely) split, Cohen said.
The polar vortex might split further in about 10 days, "but it's unclear if this will happen," Butler said. "Forecast models struggle with predicting a splitting of the vortex more than a week in advance."
Disruptions to the polar vortex are key for forecasts, as about two weeks after they happen, the troposphere gets a wallop of weird weather, which can last for weeks. Because of this week's polar vortex disruption, "there's indications we'll see some colder weather within two weeks … in the Eastern U.S., Northern Europe and East Asia," Cohen said.
For now, it's up in the air whether that means snowstorms or a rash of cold air, he said.
Meanwhile, "warmer-than-normal conditions can also occur over the Canadian Arctic and subtropical Asia and Africa," Butler said. "These effects could potentially persist for 4-6 weeks after the sudden stratospheric warming."
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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.
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