Rare monster galaxy grew rapidly 12 billion years ago … then suddenly died

11-02-2020 om 22:54 geschreven door peter  

Author and researcher, Mary A. Joyce, is the editor of the Sky Ships over Cashiers website which features cutting-edge and unusual topics.

She detailed her work investigating a variety of anomalous phenomena in her home state of North Carolina.

This includes underground military bases located near well-known tourist attractions in the state, yet, so well camouflaged that few people know they exist.

According to a source she interviewed, a city-sized secret base that is totally self-sufficient, is located underneath PARI, an astronomical education and research center, located about an hour from Asheville.

  

{ http://ufosightingshotspot.blogspot.com/  }

11-02-2020 om 20:26 geschreven door peter  

US Navy Submarine ‘Encountered 500mph UFO in Ocean’ 4 Years After Nimitz’ Sighting

Article By Simon Green - (dailystar.co.uk)

• Mike Turber, who claims to be a former Air Force intelligence expert, revealed on

‘The Hidden Truth Show’ with Jim Breslo (see videos below) that the infamous ‘Tic

Tac’ UFO captured on video by Navy pilots with the USS Nimitz carrier group off of

San Diego in 2004 is actually technology created by the US military. However, the

Navy says that it is not able to identify the object, calling it a ‘UAP’ or ‘unidentified

aerial phenomena’.

• Ever since the revelation in 2017 of the Nimitz’ UFO encounter, there has been an

overwhelming sense that there is more footage yet to be disclosed. In January, a US

Navy spokesperson confirmed that a longer video classified “secret” does exist.

Turber says that this footage would be at least 10 minutes long and is far clearer

than the first one. Turber noted that the FLIR video recorder is turned on when the

jet launches, so the entire beginning of the video seems to be missing.

• Turber claims that in 2007 or 2008, a craft matching the description of the ‘Tic Tac’

UFO was spotted hurtling through the water at 550mph by a US Navy submarine. “I

thought it was just a torpedo,” said Turber, “but, apparently not.” Turber told

the Daily Star Online that this US military craft is capable of traveling at astonishing

speeds both in the air and under the sea.

A craft matching the description of the USS Nimitz UFO was spotted by a US Navy submarine hurtling at 550mph through the water in a previously unrevealed encounter, a former US Air Force intelligence expert has claimed.

Jim Breslo                        Mike Turbo  

The sighting of a ‘tic-tac’ craft by two US Navy fighter jets in 2004 has become one of the most famous UFO videos of all time.

The US Navy is still unable to explain the object, previously identifying it as an Unidentified Aerial Phenomena.

But Mike Turber, an intelligence expert who claims to have worked in the USAF, claims the craft was actually created by the US military.

He first made his bombshell comments on The Hidden Truth Show with Jim Breslo.

And in an exclusive chat with Daily Star Online, he suggested the craft is capable of hurtling at astonishing speeds in both the air and sea.

“There was a submarine situation – that report will probably come out further down the line,” he explained.

“It (the tic-tac object) was travelling at 550mph. As far as I know, it was a Los Angeles-class submarine.

1:13:23 length Part 1 video of Jim Breslo’s interview of Mike Turber (‘Hidden Truth Show’ YouTube)

1:23:51 length Part 2 video of Jim Breslo’s interview of Mike Turber (‘Hidden Truth Show’ YouTube)

The Nimitz Encounters

{ https://exonews.org/ }

11-02-2020 om 18:36 geschreven door peter  

Now, for the first time, astronomers have found a fast radio burst (FRB) that repeats on a regular cycle.

Every 16.35 days, the signal named FRB 180916.J0158+65 follows a similar pattern. For four days, it will spit out a burst or two every hour. Then it falls silent for 12 days. Then the whole thing repeats.

Astronomers with the Canadian Hydrogen Intensity Mapping Experiment (CHIME) Collaboration in Canada observed this cycle for a total of 409 days. We don't yet know what it means; but it could be another piece in the complicated conundrum of FRBs. The research has been uploaded to pre-print server arXiv, where it awaits scrutiny from other experts in the field.

It's easy to become somewhat obsessed with fast radio bursts, a fascinating space mystery that has so far defied any attempts at a comprehensive explanation.

To recap, FRBs are hugely energetic flares of radiation in the radio spectrum that last just a few milliseconds at most. In that timeframe, they can discharge as much power as hundreds of millions of Suns.

Most of them spark once, and we have never detected them again. This makes it rather difficult to track these bursts down to a source galaxy. Some FRBs spit out repeating radio flares, but wildly unpredictably. These are easier to track to a galaxy, but so far, that hasn't brought us a great deal closer to an explanation.

Last year, the CHIME collaboration announced they had detected a whopping eight new repeating fast radio bursts, bringing the then-total of repeaters to 10 out of over 150 FRB sources. (Another paper recently brought that total up to 11.)

FRB 180916.J0158+65 was among the eight repeaters included in last year's haul; apart from its repeat bursts, initially it didn't appear to be anything special. But as the CHIME experiment continued to stare at the sky, a pattern emerged.

This is exciting, because it offers new information that can be used to try and model what could be causing FRB 180916.J0158+65.

"The discovery of a 16.35-day periodicity in a repeating FRB source is an important clue to the nature of this object," the researchers wrote in their paper.

Other objects that demonstrate periodicity tend to be binary systems - stars and black holes. The 16.35-day period could be the orbital period, with the FRB object only facing Earth during a certain part of the orbit.

FRB 180916.J0158+65 is one of the handful of FRBs that have been traced back to a galaxy. It's on the outskirts of a spiral galaxy 500 million light-years away, in a star-forming region. This means a supermassive black hole is unlikely, but a stellar-mass black hole is possible.

"The single constraint on the orbital period still allows several orders of magnitude range in companion mass amongst known stellar-mass compact object binaries: from so-called 'black widow' binary systems, consisting of a low-mass star and a powerful millisecond pulsar whose wind ablates the companion (albeit typically with few-hour orbital periods), to massive O/B stars with highly eccentric companion pulsar orbits," the researchers wrote.

Alternatively, winds from the companion object, or tidal disruptions from a black hole, may periodically somehow block the FRB radiation.

It also can't be ruled out that the FRB source is a single, lone object such as a magnetar or X-ray pulsar, although the researchers note this explanation is a little harder to reconcile with the data. That's because those objects have a wobbling rotation that produces periodicity, and none are known to wobble that slowly.

And radio pulsars that do have periodic intervals of several days are orders of magnitude fainter than FRBs. So it's still a mystery.

But remember that 11th repeater we mentioned earlier? It was found coming from an FRB astronomers had thought was a one-off; its repeats were simply too faint for the equipment that had initially been used to look for them.

This suggests that many more FRBs could be repeating, but outside our detection range. And the fact that FRB 180916.J0158+65 seemed more or less the same as other FRBs could mean that other repeating FRBs are also on a cycle - we just haven't detected those cycles yet.

So, the next step would be, of course, to continue staring at FRB 180916.J0158+65 for a bit. But it also would be pretty interesting to try and see if periodicity can be detected in other bursts as well.

"Future observations, both intensity and polarimetric, and at all wavebands, could distinguish among models and are strongly encouraged," the researchers wrote, "as are searches for periodicities in other repeaters, to see if the phenomenon is generic."

The research is available on arXiv ahead of peer review.

{ https://www.sciencealert.com/ }

11-02-2020 om 18:09 geschreven door peter  

NASA Scientists: A Lot More Dangerous Comets Exist Than We Thought

NASA scientists say a new study proves there are seven times as many big and potentially dangerous comets flying through deep space than previously thought.

The study analyzed data from the Wide-field Infrared Survey Explorer (WISE) spacecraft that tracks “long-period” comets (LPCs) that take at least 200 years to orbit around the sun. WISE data showed far more LPCs that potentially pose a serious impact risk to Earth.

“Previously the sense was that for every 100 asteroid impacts (of all sizes) we get 1 comet impact,” Dr. Joseph A. Nuth, a senior asteroid scientist at NASA’s Goddard Space Flight Center, told The Daily Caller News Foundation. “Now that we know there are more LPCs for every 100 asteroid impacts we might get 5 comet impacts.”

Astronomers previously gave broad estimates of the number of LPCs in the solar system, but researchers didn’t have a good way to detect them since they were obscured by clouds of gas and dust.

Gravitational forces can move LPCs back into the inner solar system, potentially putting them on a collision course with Earth. An LPC impact would be devastating.

“A comet impact is, on average, much more devastating than an asteroid impact, Nuth said. “Think BBs and Bullets vs. Howitzers and Nukes.”

Comets are rarer than asteroids, but can carry more than 100 times the energy of a typical asteroid. An LPC would likely impact Earth at a much higher velocity than other space objects.

“[A] higher velocity impact would release more energy and therefore would be worse,” Paul Chodas, manager of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory, told TheDCNF. “This is offset somewhat by the fact that comets are less dense than asteroids: the energy release of a comet impact would be less than that of a similarly sized asteroid impact if the velocities were the same.”

The study also determined that LPCs are more dangerous than more conventional asteroids or comets because they are twice the size on average.

“Yes, a body twice the size has eight times the mass of a smaller body and therefore delivers eight times the kinetic energy if all other factors are equal,” Nuth said. “The impact energy is proportional to the velocity squared.  So a comet moving three times the average asteroid velocity would impact with nine times the energy.”

“The potential impact of a long-period comet would be more hazardous than that of a Jupiter family comet both because the long-period comets are more likely to be larger, and because they follow orbits that would impact at higher velocities,” Chodas said.

The final reason researchers think LPCs are dangerous is their relative stealthiness compared to other space rocks. Detecting an LPC on a collusion course with Earth would be more difficult that spotting a more conventional near-Earth asteroid.

“The larger distance of comets, and the long orbital periods affect the warning time more than higher velocities: the generally larger distance of comets make the tracking observations less effective (since they are angular measurements), and the longer orbital periods mean that we don’t have multiple opportunities to see these objects at closer ranges,” Chodas said. “The distance at which a comet is discovered depends largely on the activity level of the comet.”

The difficulties inherent in detecting LPCs mean that NASA would likely have far less warning that one was on a collision course with Earth. The comet Siding Spring was detected on a trajectory that would strike the planet Mars in October of 2014, just 22 months after its discovery.

“Since Comet Siding Spring was quite active, it was discovered at a distance of 7 AU, about two years before it passed very close to Mars,” Chodas said. “A less active long-period comet might be discovered only a year before entering the inner Solar System. Establishing a precise trajectory for the comet would be challenging and likely take several months, so the warning time would likely be less than a year.”

Twenty-two months warning is far less than NASA scientists think they’d need to intercept an incoming comet. The best way to stop an asteroid or comet from hitting the Earth on such short notice may be to send a spacecraft up to intercept it. But even then, NASA researchers think they would need at least five years to construct a reliable spacecraft and man it.

“The case of Siding Spring is a reasonable example: much less than 5 years is a good guess,” Nuth said.  “Siding Spring came in from the celestial pole and was not spotted until it began to exhibit a coma. A larger body would show a coma at similar distances.”

Earth is just as vulnerable to LPCs and other space rocks as Mars nearly was to the Siding Spring Comet. Earths’ closer proximity to the Sun wouldn’t make it easier to detect a long-period comet on a collision course, according to NASA researchers.

“The discovery time is dictated mostly by the comet’s distance from the Sun and how active the comet is,” Chodas said. “If Comet Siding Spring were headed for an encounter with Earth, its discovery time would be the same.”

• Follow Andrew on Twitter

{ https://dailycaller.com/ }

11-02-2020 om 17:46 geschreven door peter  

Exclusive: Strange Russian Spacecraft Shadowing U.S. Spy Satellite, General Says

Apair of Russian satellites are tailing a multibillion-dollar U.S. spy satellite hundreds of miles above the Earth’s surface, a top U.S. military commander tells TIME, underscoring a growing threat to America’s dominance in space-based espionage and a potentially costly new chapter in Washington’s decades-long competition with Moscow.

Gen. John “Jay” Raymond, commander of the newly minted U.S. Space Force, says the Russian spacecraft began maneuvering toward the American satellite shortly after being launched into orbit in November, at times creeping within 100 miles of it. “We view this behavior as unusual and disturbing,” Raymond says. “It has the potential to create a dangerous situation in space.” Raymond says the U.S. government has expressed concern to Moscow through diplomatic channels.

The confrontation marks the first time the U.S. military has publicly identified a direct threat to a specific American satellite by an adversary. The incident parallels Russia’s terrestrial encounters with the U.S. and its allies, including close calls between soldiers, fighter jets and warships around the world. Observers worry that space is now offering a new theater for unintentional escalation of hostilities between the long-time adversaries.

Pentagon, White House and Congressional backers, say the incident demonstrates the need for the Space Force, which President Donald Trump established in December when he signed the National Defense Authorization Act into law. It became the first new military service since the Air Force was created in 1947.

The Space Force, for which the White House is requesting $15 billion in this week’s budget proposal, represents a strategic shift from passively operating and observing satellites to actively defending them. Space warfare doctrine remains a work in progress, but Raymond has spoken about the need to mobilize Space Command against perceived threats because other nations, especially Russia and China, have become increasingly sophisticated at building arsenals of lasers, anti-satellite weapons and state-of-the-art spacecraft designed to render the U.S. deaf, mute and blind in space.

At the same time, the expansion of military operations in space harks back to another hallmark of the Cold War competition between Washington and Moscow: massive spending on perceived threats, regardless of the cost.

For those monitoring waste, fraud and abuse in the military industrial complex, the Russian maneuver and the Pentagon’s response also portends a new front in the effort to keep real and potential threats from becoming a budgetary sinkhole. The history of U.S.-Russia military competition is full of examples of perceived threats that require costly responses.

“The initial costs of setting up the Space Force are likely a small down payment on an undertaking that could cost tens of billions of dollars in the years to come,” says William D. Hartung, director of the arms and security project at the Center for International Policy. “The last thing we need is more bureaucracy at the Pentagon, but that’s exactly what the Space Force is likely to give us. Creating a separate branch of the armed forces for space also risks militarizing U.S. space policy and promoting ill-advised and dangerous projects that could involve deploying weapons in space.”

The Russian embassy did not respond to requests for comment about the allegedly threatening maneuvers by its satellites. The Kremlin has previously stated they are not weapons, but rather “inspector” spacecraft engaged in an “experiment.”

U.S. military analysts first noticed something peculiar after Russia launched its spacecraft into orbit November 26 from Plesetsk Cosmodrome aboard a Soyuz rocket. The Russian satellite had been in orbit less than two weeks when, bafflingly, it split in two. As the analysts looked closer, they suspected that a second smaller satellite was somehow “birthed” from the first one. “The way I picture it, in my mind, is like Russian nesting dolls,” Raymond says. “The second satellite came out of the first satellite.”

The maneuver was later confirmed on Dec. 6 when the TASS news agency cited Russia’s Defense Ministry saying the two had separated. “The purpose of the experiment is to continue work on assessing the technical condition of domestic satellites,” the statement said.

However, the satellites, identified as Cosmos 2542 and Cosmos 2543, appeared to be carrying out another mission. By mid-January, they were sidling near the American satellite, identified as USA 245, known to space experts as a KH-11.

The U.S. satellite, part of a reconnaissance constellation codenamed Keyhole/CRYSTAL, is operated by the National Reconnaissance Office (NRO), the secretive intelligence agency headquartered in Chantilly Va. Although the NRO refuses to comment on the large school bus-sized satellites, the KH-11’s capabilities are often compared by experts in the field to the Hubble Space Telescope. Instead of staring into the vast expanse of space, however, the satellites’ sensors and cameras are focused into the heart of foreign adversaries’ top-secret military installations

A KH-11 satellite, known as USA 224, is widely believed by analysts to have taken the image of Iran’s Imam Khomeini Space Center that President Donald Trump posted to Twitter in August. The photo was so detailed, you could make out the Farsi characters written along the edge of the launchpad. The KH-11 constellation, which consists of four satellites that maintain constant Earth observation, operate in a polar orbit above the rotating Earth, enabling them to cover its entire surface.

Russia’s curious space activities were first noted on Twitter last week by Michael Thompson, an amateur satellite tracker, who used publicly available data to speculate on what it was up to. “The relative orbit is actually pretty cleverly designed, where Cosmos 2542 can observe one side of the KH11 when both satellites first come into sunlight, and by the time they enter eclipse, it has migrated to the other side,” Thompson wrote in a series of tweets. “This is all circumstantial evidence, but there are a hell of a lot of circumstances that make it look like a known Russian inspection satellite is currently inspecting a known US spy satellite.”

President Donald Trump and General John "Jay" Raymond attend a ceremony marking the establishment the U.S. Space Command at the White House on Aug. 29, 2019.

Chen Mengtong—China News Service/VCG via Getty Images

Raymond says he’s concerned because Russia is demonstrating capabilities the U.S. first saw three years ago, when Moscow tested the “Russian nesting doll” technology. “In 2017, they launched a satellite, it launched another satellite,” he says. “The satellites exhibited characteristics of a weapon system when one of those satellites launched a high-speed projectile into space.”

While Raymond’s allegation couldn’t be verified, the U.S. did raise the issue in 2018, warning about Russia’s “very troubling” behavior at the U.N.’s Conference on Disarmament that year without providing specifics.

Moscow’s intent with the current mission remains unknown, but the Russian spacecraft should be capable of capturing high-resolution imagery of the American satellite as it conducts its mission, spying deep into adversaries’ territory. It’s akin to handing over a state-of-the art spy satellite to Russian scientists for forensic analysis.

Brian Weeden, a former Air Force officer and expert in space security at the Secure World Foundation, says the Russian satellites’ positioning could allow it to determine things like where the KH-11 is “pointing—and thus what ground targets its taking picture of—as well as the general operating schedule and usage.”

Further, if the Russian satellites are outfitted with electronic emissions probes, they could listen for radio frequency signals to try figure out how the KH-11 communicates and even attempt to intercept those communications, which are likely encrypted, says Todd Harrison, director of the Aerospace Security Project at the Center for Strategic and International Studies. “There are a lot of things it could be doing,” Harrison says. “They could simply be practicing on-orbit maneuvers or signaling to the United States that they have this capability.”

The Keyhole program is 44 years old and the satellites are widely known to have similar capabilities as the Hubble Telescope. The U.S., China and other nations have already shown the ability to launch spacecraft into close orbit with their own satellites. The Kremlin could be showing the U.S.—in a very obvious way—that it has joined the club.

From Raymond’s standpoint, however, maneuvering close to a foreign satellite for an “inspection” is virtually indistinguishable from staging an attack to damage, disrupt or destroy it. “It’s clear that Russia is developing on-orbit capabilities that seek to exploit our reliance on space-based systems that fuel our American way of life,” he says. Raymond wouldn’t comment specifically on Russia’s intentions with the shadowing satellites

Over the past decade, space weaponry has gone from the stuff of science fiction to reality. A flurry of advancements from the U.S., Russia and China has altered the image of outer space as a peaceful sanctuary and instead stoked fears that an arms race has extended into the heavens.

But even if the Russian satellites are doing the most intrusive things the Pentagon and outside observers imagine, none of them would violate treaties or international law. Absent binding agreements, the incident portends a growing a cat-and-mouse game in space. “We prefer space to remain free of conflict,” Raymond says. “We think that responsible space-faring nations need to have conversations about developing these norms going forward.”

It is a historical truth that where humans have ventured, violence has followed. But conflict in space isn’t in any nation’s interest. There are more than 1,000 American satellites circling the planet, enabling everything from commerce, banking, transportation and communications. Russia, China and other developed nations have also grown increasingly dependent on satellites for commercial as well as military purposes, which raise the risks for miscalculation.

The U.S. government’s space-based operations are among the most highly technical and classified secrets in its possession. Raymond’s willingness to go on the record about the ongoing event provides a glimpse into what military officials see as an increasingly congested and contested environment.

Robert Cardillo, the former director of the U.S. National Geospatial-Intelligence Agency, says space is a “messy environment,” which without established rules, could turn into the Wild West. An attack on a satellite constellation, such as GPS, which is owned and operated by the U.S. Air Force, could have far-reaching consequences like halting ATM banking transactions or causing a blackout in navigation applications on users’ smartphones, which occurs billions of times a day around the globe.

The developments hark back to military concept that helped keep the world safe from nuclear apocalypse during the Cold War. Mutual assured destruction (MAD)—the military doctrine that posited a nuclear strike from one nation would result in a full-scale counterattack from the other—helped prevent the U.S. and the Soviet Union from using the massive arsenals they each amassed during decades of armed standoff.

But MAD eventually became backstopped by a series of treaties and open lines of communication designed to avoid accidental escalation of conflict. The U.S., Russia and other nations have yet to establish a similar diplomatic structure for space, and experts warn of the dangers of weaponizing the cosmos without them. “Deterrence is something we just haven’t dealt with,” in space Cardillo says. “If you make it, you can break it.”

—With reporting by John Walcott/Washington

WRITE TO W.J. HENNIGAN AT WILLIAM.HENNIGAN@TIME.COM.

{ https://time.com/ }

11-02-2020 om 17:26 geschreven door peter  

The mystery of the Bermuda Triangle Solved???

{  https://beforeitsnews.com/ }

11-02-2020 om 16:10 geschreven door peter  

UFO As Big As Moon, Caught In Suns Gravity For Months, UFO Sighting News.

Date of sighting: Feb 10, 2020
Location of discovery: Earths Sun, 45-45 degree 
Source software: 

• https://www.jhelioviewer.org
  

I found this black triangle UFO on our sun a few months ago and I am still watching it. I can see it daily using this special software designed by the ESA (european space admistration). Anyone can download it and use it. This shows me that the triangle UFO is still there. Its black, so we know its surface is heat resistant or has some kind of protective electronic shield around it. 

Its unbelievable that NASA has never even mentioned this triangle craft, but I guess they think the public would panic if they knew. Because admitting its a craft would mean admitting that intelligent aliens exist. 
Scott C. Waring - Taiwan

{ https://www.etdatabase.com/ }

11-02-2020 om 15:19 geschreven door peter  

Hey, Google, Where Are the Aliens? How UFO Enthusiasts Utilize Tech Giant’s Services to Search ETS in Antarctica

In December last year, UFO fans were engaged in debates over a large mysterious hole in Antarctica. Users believed the humongous structure was an entrance to a secret military facility, which first appeared in 2007. However, it vanished shortly afterwards. Twelve years later, it was found again on Google Maps.

It appears that Antarctica has long pulled in fans of conspiracy theories since wild stories surfaced that high-ranking Nazi officers could have escaped and gone to Antarctica. However, Antarctica has become the most famous place for hunting aliens using Google’s services. Here are the most exciting finds.

The Alien Face

One may believe that aliens want humanity to find them after seeing the alien image. A huge alien-like face on snow was discovered in Antarctica via Google Earth. Footage posted on Instagram by ufo_scandinavia quickly made the rounds on the internet with some social media users claiming the structure was left by aliens or an ancient civilisation that lived in Antarctica.

Alien Ship

UFO fans got baffled after YouTube user MrBB333 shared what he claims is a possible capsized ship in Antarctica. On his channel, he posted a man showing how he found a long cylindrical shape in the ground via Google Earth.

Strange Disc-Shaped Object on Mountain

It is another find that baffled conspiracy theorists. YouTube user Sandra Elena Andrade posted a video in December 2019 showing a massive black object that many commenters said was an alien ship. The woman discovered the mysterious object through Google Earth.

Ancient Alien City

YouTube channel thirdphaseofmoon co-author Blake Cousins claimed to have found an entrance to a hidden base, thought to be owned by aliens. He said that the dark shape on the snow looks like each one has a tunnel or cave that possibly connected underneath the show. Some social media users believed Blake’s version, while others thought this could be a hiding spot for a government project or Nazis.

Massive Hole

The YouTube channel thirdphaseofmoon stunned UFO followers again when they found a mysterious hole on Google Maps in December 2019. The humungous hole first appeared in 2007 but disappeared shortly afterward. According to Brett and Blake Cousins, this cave could potentially accommodate up to thousands of people. Brett added that it is big enough for flying saucers and spacecraft or even assets in our military to fly.

{ https://www.latest-ufo-sightings.net/ }

11-02-2020 om 15:07 geschreven door peter  

Space Junk: How Much Debris are There in Earth's Orbit?

11-02-2020 om 02:01 geschreven door peter  

Researchers concluded that even a contained nuclear conflict would take a toll on Earth’s oceans and potentially disrupt the human food web. “The impacts are huge,” a scientist said.

A mushroom cloud erupts during the Castle Bravo nuclear weapon test at Bikini Atoll in 1954.

Image via U.S. Department of Energy/ University of Colorado Boulder.

You’ve likely heard of nuclear winter, a hypothesis explored by decades of scientific research. It’s the idea that – following the firestorms produced in an all-out nuclear war – the soot lifted into Earth’s stratosphere would cause serious cooling, and subsequent crop failures and famines. Now a new study has looked at how even a relatively contained nuclear conflict – for example, a hypothetical war between India and Pakistan – might shift the chemistry of Earth’s oceans. The reasoning is reminiscent of that behind nuclear winter: soot lifted into the atmosphere would cause cooling. In the new study, the researchers concluded that even a contained conflict would “take a toll” on the oceans and potentially disrupt the human food web.

Nicole Lovenduski of University of Colorado Boulder (CU Boulder) led the study. She commented in a statement:

The impacts are huge.

The journal Geophysical Research Letters published the new study in late January 2020.

These researchers used global climate models to conduct their simulations. They looked at four possible nuclear conflicts, including three in India/Pakistan of differing magnitudes (5 teragrams, 27 teragrams, and 47 teragrams of soot produced, respectively; a teragram is equal to one trillion grams or 1,000 kilotons), and one all-out U.S./Russia case with 150 teragrams of soot produced. Writing at LaboratoryEquipment.com, Michelle Taylor penned a succinct explanation of what would happen in even the “tamest” of the India-Pakistan simulations. She wrote:

… the researchers found that the conflict would likely generate huge amounts of black carbon high in Earth’s atmosphere, causing the globe to cool. Interestingly, the researchers found that the fallout from a nuclear detonation would come in two stages: the first within one year, and the second between three and five years post-bombing.

Soon after denotation and no longer than one year later, global climate models showed the acidity of the world’s oceans would likely dip. Years later, the world’s salt water would begin to suck up more carbon dioxide from the air. Supplies of carbonate in the oceans would shrink, removing the key ingredient that corals use to maintain their reefs and oysters use to sustain their shells.

Lovenduski told Taylor that – beyond taking a toll on crustaceans – a major disruption of the oceanic food web would undoubtedly severely impact the human food chain. Taylor wrote:

That’s because there are more than 3 billion people in the world today who depend on ocean fisheries for protein and/or income.

The shell of an ocean pterapod dissolves when exposed to acidic conditions in a lab.

Image via NOAA/ CU Boulder.

Brian Toon, also of CU Boulder, was a co-author on the study. He commented in the team’s statement:

This result is one that no one expected. In fact, few people have previously considered the impact of a nuclear conflict on the ocean.

Lovenduski commented:

A lot of things would change in the oceans once you dim the lights [via soot in the atmosphere]. The way the water moves in the ocean, for example, is sensitive to how much heat it gets from the atmosphere …

It makes me question whether organisms could adapt to such a change. We’re already questioning whether they can adapt to the relatively slower process of man-made ocean acidification, and this would happen much more abruptly.

Lovenduski said it’s too soon to say for sure what the fate of shelled creatures in the oceans would be if nuclear war broke out. She said she hopes that her group’s findings will bring more attention to the wide-ranging devastation that would follow even a limited nuclear exchange. There’s no such thing, she said, as a minor nuclear war, adding:

I hope this study helps us to gain perspective on the fact that even a small-scale nuclear war could have global ramifications.

A U.S. Army nuclear test at Bikini Atoll, Micronesia, on July 25, 1946. The wider, exterior cloud is a condensation cloud, not a classic mushroom cloud. Read more about this image. A new study shows that even a limited nuclear conflict could have damaging effects on Earth’s oceans. The bombs would not have to explode over the ocean for the effects to take place.

Image via Wikimedia Commons.

• Bottom line: Scientists used global climate models to study various scenarios involving limited nuclear conflicts. The researchers called the impacts “huge.”
• Source: The Potential Impact of Nuclear Conflict on Ocean Acidification
• Via University of Colorado Boulder
• Via LaboratoryEquipment.com

{ https://earthsky.org/ }

11-02-2020 om 01:35 geschreven door peter  

Devastating solar storms could be far more common than we thought

By Brandon Specktor - Senior Writer

These powerful storms can knock out satellites and power grids, and we may be due for one every 25 years.

On June 20, 2013, at 11:15 p.m. EDT, the sun shot out a solar flare (left side), which was followed by an eruption of solar material shooting through the sun's atmosphere.

(Image: © NASA Goddard)

The sun constantly bombards Earth with wispy belches of plasma called solar wind. Normally, the planet's magnetic shield soaks up the brunt of these electric particles, producing stunning auroras as they surge toward Earth's magnetic poles. But every so often, there comes a solar sneeze powerful enough to body-slam our atmosphere. 

These severe space weather events — known as solar storms — compress Earth's magnetic shield, releasing enough power to blind satellites, disrupt radio signals and plunge entire cities into electrical blackouts. According to a study published Jan. 22 in the journal Geophysical Research Letters, they may be much more common than previously thought.

In the new study, researchers analyzed a catalog of Earth's magnetic field changes going back to 1868; years that showed the strongest spikes in geomagnetic activity coincided with the most severe solar storms. They found that severe storms (those capable of disrupting some satellites and communications systems) occurred in 42 of the last 150 years, while the most extreme storms — "great" superstorms, which cause significant damage and disruption — occurred in six of those years, or once every 25 years.

• Related: How a 1967 solar storm nearly led to nuclear war

"Our research shows that a super-storm can happen more often than we thought," study co-author Richard Horne, a space weather researcher at the British Antarctic Survey, said in a statement. "Don't be misled by the stats. It can happen any time. We simply don't know when."

Attack of the sun

For the new study, the researchers consulted the world's oldest continuous geomagnetic index, known as the aa index. 

Since 1868, the index has recorded changes in Earth's magnetic field as observed by two research stations on opposite sides of the planet, one in Australia and the other in the U.K. Every 3 hours, ground-based sensors at each station record local changes in magnetic field activity; after combining the daily averages from each station, scientists get a general picture of magnetic field activity across the entire planet.

Because the study authors were concerned only with the most extreme solar events over the last 150 years, they focused on the top 5% of geomagnetic spikes recorded each year. With this data, the authors ranked the top 10 years with the most severe geomagnetic activity from 1868 to present day. Those years, from most to least active, were 1921, 1938, 2003, 1946, 1989, 1882, 1941, 1909, 1960 and 1958.

Unsurprisingly, most of those years were associated with powerful geomagnetic storms. 

"The earliest ones would have been reported in terms of auroras ('northern lights') at low latitudes, and disruptions to telegraph communications," lead study author Sandra Chapman, an astrophysics professor at the University of Warwick in England, told Live Science in an email. "As aviation and radio came into widespread use, reports centered on disruptions to those."

A geomagnetic storm in May of 1921, for example, caused widespread radio and telegraph outages across the world, resulting in at least one telegraph operator's instrument bursting into flames and setting his office on fire, according to a report published in 2001 in the Journal of Atmospheric and Solar-Terrestrial Physics. The northern and southern auroras (which intensify during solar storms) were also visible at far lower latitudes than usual, with one observatory claiming to detect the southern lights from the island of Samoa, just 13 degrees south of the geomagnetic equator.

More recent solar storms, such as a massive flare that swept over Earth on Halloween 2003, disrupted communications satellites and caused other spacecraft to tumble out of control. In March 1989, a gargantuan solar storm plunged the entire province of Quebec, Canada, into darkness and left millions of people without power for 12 hours.

Earth hasn't been hit with a solar super-storm in nearly two decades (though a large, potentially damaging solar ejection passed by us in 2012). Since then, our world has become more networked and satellite-dependent; the precise impacts the next superstorm will have on our society aren't well understood, Chapman said. Studies like this can help scientists predict the likelihood that a powerful space storm might hit Earth in a given year, which could lead to better preparedness, she added.

Powerful solar ejections occur more frequently when there are a lot of sunspots on the sun's surface. Sunspot activity tends to peak approximately every 11 years, during a period called the solar maximum. The last solar maximum occurred in 2014.

• 15 Unforgettable images of stars
• The 12 strangest objects in the universe
• 9 Ideas about black holes that will blow your mind

Originally published on Live Science.

{ https://www.livescience.com/ }

11-02-2020 om 01:16 geschreven door peter  

Researchers Find Presolar Grains in Unusual Inclusion from Allende Meteorite

Scientists from Washington University, St. Louis, Caltech and the University of Chicago have found presolar grains — tiny bits of solid interstellar material formed before the Sun was born — in Curious Marie, a sample of the famous Allende meteorite.

Curious Marie is a sample of the Allende meteorite, which fell in northern Mexico in February 1969. The white, fuzzy-looking features in this fragment are calcium-aluminum-rich inclusions — some of the first solids to condense in the Solar System. Image credit: The Planetary Society.

Curious Marie is a notable example of an inclusion, or a chunk within a meteorite, called a calcium-aluminum-rich inclusion (CAI).

These objects, some of the first to have condensed in the Solar Nebula, help cosmochemists define the age of the Solar System.

“What is surprising is the fact that presolar grains are present. Following our current understanding of solar system formation, presolar grains could not survive in the environment where these inclusions are formed,” said Dr. Olga Pravdivtseva, a researcher in the Physics Department and the McDonnell Center for the Space Sciences at Washington University, Saint Louis.

In 2016, a research team from the University of Chicago discovered evidence in Curious Marie that a rare element called curium was present during the formation of the Solar System.

This fragment of the Allende meteorite and curium are named after the Nobel Prize-winning physicist and chemist Marie Curie, whose pioneering work laid the foundation of the theory of radioactivity.

In the new study, Dr. Pravdivtseva and colleagues used noble gas isotopic signatures to show that presolar grains of silicon carbide are present in Curious Marie.

That’s important because presolar grains are generally thought to be too fragile to have endured the high-temperature conditions that existed near the birth of our Sun.

But not all CAIs were formed in quite the same way.

“The fact that silicon carbide is present in refractory inclusions tells us about the environment in the Solar Nebula at the condensation of the first solid materials,” Dr. Pravdivtseva said.

“The fact that silicon carbide was not completely destroyed in Curious Marie can help us to understand this environment a little bit better.”

“Many refractory inclusions were melted and lost all textural evidence of their condensation. But not all.”

The scientists had 20 mg of Curious Marie to work with, which is a relatively large sample from a cosmochemistry perspective.

They heated it up incrementally, increasing temperature and measuring the composition of four different noble gases released at each of 17 temperature steps.

“Experimentally, it is an elegant work. And then we had a puzzle of noble gas isotopic signatures to untangle. For me, it is like solving a mystery,” Dr. Pravdivtseva said.

Other scientists have looked for evidence of silicon carbide in such CAIs in meteorites using noble gases before, but Dr. Pravdivtseva’s team the first to find it.

“It was beautiful when all noble gases pointed to the same source of the anomalies — silicon carbide,” Dr. Pravdivtseva said.

“Not only do we see silicon carbide in the fine-grained CAIs, we see a population of small grains that formed at special conditions.”

“This finding forces us to revise how we see the conditions in the early Solar Nebula.”

• The results were published in the journal Nature Astronomy.

{ http://www.sci-news.com/ }

11-02-2020 om 00:56 geschreven door peter  

Our sun will never look the same again thanks to two solar probes and one giant telescope

By Meghan Bartels 

An artist's depiction of the ESA-NASA Solar Orbiter and NASA's Parker Solar Probe studying the sun.

(Image: © Solar Orbiter: ESA/ATG medialab; Parker Solar Probe: NASA/Johns Hopkins APL)

It's always sunny for heliophysicists, but especially so now.

The Solar Orbiter spacecraft, a collaboration between the European Space Agency and NASA, launched yesterday (Feb. 9), less than two weeks after the first public image from a massive new solar telescope showed off the structure of our star in more detail than humans have ever seen. On that same day, Jan. 29, NASA's Parker Solar Probe made its closest swing pass the sun to date — a record it will continue to break until 2025.

"It's a great time to be a heliophysicist; we're launching lots of new missions," Nicky Fox, head of NASA's Heliophysics Division, told Space.com. "It's a very strategic way that we're looking at this system [of instruments], as one large observatory."

• Related: What's inside the sun? A star tour from the inside out

Although the three missions weren't designed as a suite, they complement one another well. The Parker Solar Probe, which launched in August 2018, is flying closer to the visible surface of the sun than any spacecraft to date. That trajectory carries the spacecraft deep into the sun's atmosphere, called the corona, where the probe's instruments focus on the spacecraft's immediate surroundings, measuring magnetic fields and particles of plasma, the charged soupy state of matter that makes up the sun.

Solar Orbiter won't fly as close to the sun, but it brings unique skills. First, it carries two types of instruments. One set, like Parker's, will study the spacecraft's surroundings; the other, a set of telescopic instruments, will observe the visible surface of the sun itself at a distance. And partway through its mission, Solar Orbiter will leave the belt around the sun's middle, called the ecliptic, and begin circling the sun at a tilt, allowing the spacecraft to use those telescopic instruments to produce the first-ever images of the sun's poles.

The National Science Foundation's Inouye Solar Telescope is stuck here on Earth, and construction is still underway. But once all of its instruments are operational, there will be plenty more images like the "caramel corn" picture that scientists published in January —  the highest-resolution solar image to date. "The Inouye Solar Telescope is a microscope on the sun," Valentin Martínez Pillet, director of the National Solar Observatory, which runs the facility, told Space.com. The observatory will also measure the wavelengths of light emitted by the sun and decipher the magnetic signature of light that is under the influence of the sun's magnetic field.

Although the three projects are separate endeavors, both scientists said they and their colleagues are awfully excited about pulling all the data together.

We have so few close-up observations of the sun that being able to compare two separate locations is automatically valuable, no matter where each spacecraft is. Solar Orbiter's final schedule was dependent on its precise launch date, but as mission personnel evaluated how each timetable aligned the spacecraft with the Parker Solar Probe's close approaches, they found intriguing opportunities regardless of the launch date, Fox said.

The Inouye Solar Telescope is even easier to integrate into an observational program, Martínez Pillet said; its personnel know precisely where the two spacecraft will be at any given time and can match up the telescope accordingly.

Combining the data from all three observatories is vital for scientists to accomplish the goal that drives the missions: to understand the sun and its influence throughout the solar system. The impacts of the sun's antics ripple across the solar system as a set of phenomena called space weather.

In Earth's neighborhood, space weather can interfere with the technology modern society is ever more reliant upon, particularly navigation and communication satellites. Space weather is also a hazard for astronauts traveling farther from Earth, as it can harm both their technology and their bodies. Ultimately, solar scientists want to be able to predict space weather in much the same way meteorologists predict terrestrial weather. "We are 50 or 100 years lagging from what terrestrial weather is in terms of prediction," Martínez Pillet said.

That's because scientists just don't know enough about how the sun works. "We're able to predict a single second on the sun," he said. "I'm exaggerating — well, no, I don't think I'm exaggerating. We're not able to have any realistic predictive capabilities today, but as soon as you get the physics right, then you start being able to develop predictive capabilities."

One particular challenge in understanding space weather is the sheer distance involved, and that's where the trio of missions will be valuable, Martínez Pillet said. "One space-weather event has a combination of scales," he said. "It's triggered at really small scales, and it's a huge thing that propagates all over the heliosphere and probably can hit several planets at the same time." But by the time space weather reaches Earth, it's been influenced by millions of miles of space; it's much fresher where the Parker Solar Probe and the Solar Orbiter can study it.

There's another reason to understand space weather: It could tell scientists where to look for signs of life elsewhere in the universe. After all, while we humans have a soft spot for the sun, it's just a star like any other — which means that scientists can apply what these three missions discover to all the stars we'll never be able to see as clearly. And while space weather is vexing to Earth, it could be deadly in solar systems that surround smaller, more active stars.

And there should be plenty for the trio of projects to study in the coming years. Right now, the sun is pretty quiet, but over the next five or six years, the sun's activity will increase — and both the Parker Solar Probe and the Solar Orbiter will be on hand to see what happens during that period. 

"They are really, truly voyages of discovery, and we're doing fundamental physics and understanding how a star works," Fox said.

Of course, even three high-powered missions won't solve every mystery about the sun. 

"We know right now what we don't know, but we're going to find a whole lot more things that we don't know," Fox said. "That's why it's nice that these missions are so long, so you have time to develop these new questions, this new thirst for knowledge."

• NASA's Parker Solar Probe mission to the sun in pictures
• World's largest solar telescope produces never-before-seen image of our star
• Stunning NASA image lets you watch the sun explode in real time

Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels.

Follow us on Twitter @Spacedotcom and on Facebook.

{ https://www.space.com/ }

11-02-2020 om 00:41 geschreven door peter  

NEXT NASA MARS ROVER WILL SPORT A ROCK-VAPORIZING LASER

Mars 2020's mast, or "head," includes a laser instrument called SuperCam that can vaporize rock material and study the resulting plasma.

Credit: NASA/JPL-Caltech
› Full image and caption

{ https://futurism.com/the-byte }

11-02-2020 om 00:15 geschreven door peter  

A full moon is opposite the sun. We see all of its dayside.

Illustration via Bob King.

The coming full moon is February 9 at 07:33 UTC. That means the night of February 8-9, 2020, will bring the fullest moon for those in the Americas. The moon appears full to the eye for two to three nights. However, astronomers regard the moon as full at a precisely defined instant, when the moon is exactly 180 degrees opposite the sun in ecliptic longitude.

It’s that feature of a full moon – the fact that it’s opposite the sun as viewed from Earth – that causes a full moon to look full.

A kiss under the full moon of November 3, 2017, via our friend Steven Sweet of Lunar 101-Moon Book. He was at Port Credit, a neighborhood in the city of Mississauga, Ontario, Canada … at the mouth of the Credit River on the north shore of Lake Ontario.

Why does a full moon look full? Remember that half the moon is always illuminated by the sun. That lighted half is the moon’s day side. In order to appear full to us on Earth, we have to see the entire day side of the moon. That happens only when the moon is opposite the sun in our sky. So a full moon looks full because it’s opposite the sun.

That’s also why every full moon rises in the east around sunset – climbs highest up for the night midway between sunset and sunrise (around midnight) – and sets around sunrise. Stand outside tonight around sunset and look for the moon. Sun going down while the moon is coming up? That’s a full moon, or close to one.

Just be aware that the moon will look full for at least a couple of night around the instant of full moon.

• Read more: What are the full moon names?

Often, you’ll find two different dates on calendars for the date of full moon. That’s because some calendars list moon phases in Coordinated Universal Time, also called Universal Time Coordinated (UTC). And other calendars list moon phases in local time, a clock time of a specific place, usually the place that made and distributed the calendars. Translate UTC to your local time.

Want to know the instant of full moon in your part of the world, as well as the moonrise and moonset times? Visit Sunrise Sunset Calendars, remembering to check the moon phases plus moonrise and moonset boxes.

If a full moon is opposite the sun, why doesn’t Earth’s shadow fall on the moon at every full moon? The reason is that the moon’s orbit is tilted by 5.1 degrees with respect to Earth’s orbit around the sun. At every full moon, Earth’s shadow sweeps near the moon. But, in most months, there’s no eclipse.

A full moon normally passes above or below Earth’s shadow, with no eclipse.

Illustration by Bob King.

As the moon orbits Earth, it changes phase in an orderly way. Follow these links to understand the various phases of the moon.

New moon
Waxing crescent moon
First quarter moon
Waxing gibbous moon
Full moon
Waning gibbous moon
Last quarter moon
Waning crescent moon

• Bottom line: A full moon looks full because it’s opposite the sun. Its lighted face is turned entirely in Earth’s direction. The next full moon is February 9 at 07:33 UTC. (Translate UTC to your time).
• Read more: 4 keys to understanding moon phases

{ https://earthsky.org/ }

10-02-2020 om 23:53 geschreven door peter  

Scientists built an AI to figure out what the universe is made of

STORY BY Tristan Greene

A multi-university team of researchers from Japan recently used the world’s fastest astrophysics-simulation supercomputers to develop an AI system capable of predicting the structure of the universe itself. The scientists hope that in doing so they’ll unlock the mysteries surrounding dark matter and dark energy.

Dubbed “Dark Emulator,” the AI system parses gigantic troves of astrophysics data and uses the information to build simulations of our universe. It taps into a massive database full of information gleaned from special telescopes and compares current data with what scientists expect based on theories surrounding the universe’s origin.

• Study: Our universe may be part of a giant quantum computer

The simulation basically attempts to demonstrate what the universe might look like, including its edges, based on the big bang theory and the subsequent rapid expansion that continues to take place.

According to Phys.Org, the lead author on the team’s research paper, Takahiro Nishimichi, said:

We built an extraordinarily large database using a supercomputer, which took us three years to finish, but now we can recreate it on a laptop in a matter of seconds. I feel like there is great potential in data science.

Using this result, I hope we can work our way toward uncovering the greatest mystery of modern physics, which is to uncover what dark energy is.

The hope here is that by understanding the general cosmology of the entire universe, scientists will be able to from better theories on how dark matter works. We currently assume that most of the universe is made up of dark matter. The “void of space” as it were, isn’t a void but composed of energized matter that, so far, can’t be directly observed.

But we’re currently unable to prove dark matter exists through scientific rigor, observation, and measurement. And that leaves astrophysicists struggling to come up with a unified theory of the universe that encompasses all the different ideas in play. How do we reconcile the Big Bang, Heisenberg’s Uncertainty Principal, Einstein’s Relativity, and Newton’s Laws of thermodynamics with modern quantum mechanics and dark energy theories?

The team from Japan hopes we do so with the information we’re able to glean from Dark Emulator. The AI system doesn’t just analyze data for loose ends, it learns from each simulation it creates and uses the output to inform the next iteration.

It does this by analyzing the invisible tendrils between galaxies and performing astronomical (literally) feats of mathematics to create more precise simulations. According to a paper the team published in Astrophysical Journal, it’s incredibly accurate:

The emulator predicts the halo–matter cross-correlation, relevant for galaxy–galaxy weak lensing, with an accuracy better than 2% and the halo autocorrelation, relevant for galaxy clustering correlation, with an accuracy better than 4%.

Eventually, this technology could help flesh out our understanding of the universe and allow scientists to determine exactly what dark matter is and how dark energy works. For now, this means filling in some of the massive blanks we have in our understanding of what the universe actually looks like beyond our front porch.

But in the future, having a clear understanding of dark energy could bring about myriad far-off science fiction technologies such as warp drives, time-travel, and teleportation. That is, of course, if dark matter even exists.

{ https://thenextweb.com/ }

10-02-2020 om 23:33 geschreven door peter  

We think of Uranus and Neptune almost as twins. In some ways, they are very similar. But a new study by researchers at PlanetS explains why, in some aspects, they are also radically different.

Uranus (left) and Neptune (right). While the 2 ice giant planets have similarities, they also have significant differences, which might be explained by impacts from other large bodies in the early solar system.

Image via NASA/ JPL/ PlanetS.

We tend to lump Uranus and Neptune together in our thoughts, almost as if they’re twin worlds. They are nearly the same size – bigger than Earth, but smaller than Jupiter or Saturn – and both are bluish or bluish-green, with deep atmospheres and icy interiors. But, though superficially similar, Uranus and Neptune are really quite different. They’re more different from each other than most people think. And, though their differences still haven’t been fully explained, it now seems that mighty collisions with careening planet-sized bodies – early in solar system history – might be the key.

Researchers of the National Centre of Competence in Research PlanetS (PlanetS) at the University of Zurich in Switzerland ran computer simulations to explore the role of collisions in shaping the differences between Uranus and Neptune. The findings were announced by PlanetS on February 4, 2020, with the associated research paper first published on November 22, 2019.

Uranus and Neptune are the two most distant known major planets in our solar system. Both are now considered ice giants. Both are fundamentally different from the larger gas giants Jupiter and Saturn, and from smaller rocky worlds like Earth. Uranus and Neptune have similar masses and internal compositions. Their outer atmospheres are composed of hydrogen, helium and methane, while their mantles are a combination of water, ammonia and methane ices, and their cores are a mix of rock and ice.

Uranus tends to have a blander appearance than Neptune and is mostly cloudless. Neptune’s atmosphere has darker bands than that of Uranus, with streaks and wisps of white clouds, as well as a large “dark spot.”

But there are also more significant differences between the two worlds, and the researchers wanted to know why. According to a statement by Christian Reinhardt, one of the PlanetS members:

… there are also striking differences between the two planets that require explanation.

Diagram depicting the the formation of both Uranus and Neptune, and how they evolved differently due to impacts from other large objects in the early solar system.

Image via Reinhardt & Helled/ ICS/ University of Zürich/ PlanetS.

Another team member, Joachim Stadel, pointed out that, unlike Neptune and Earth and most other major planets in our solar system, Uranus doesn’t rotate around an axis that lies nearly perpendicular with respect to the plane of its orbit. Instead:

… Uranus and its major satellites are tilted about 97 degrees into the solar plane, and the planet effectively rotates retrograde with respect to the sun.

Another key difference is that the larger moons of Uranus are in stable orbits that are aligned with the tilt of the planet. But Neptune’s largest moon, Triton, circles the planet at a very inclined orbit.

These differences suggest that Uranus’ moons formed from the same disk of dust and gas that the planet itself did, while Triton was probably once a separate object captured by Neptune’s gravity.

According to the researchers, these and other differences point to different kinds of impacts that affected the two planets long ago.

Size comparison of Earth and Neptune. According to the new study, objects with about 1 to 3 Earth masses collided with both Uranus and Neptune after they formed. Uranus was just grazed, while Neptune suffered a head-on impact.

Image via NASA/ Sky & Telescope.

The researchers ran computer simulations in order to explore a range of different possible collisions on both planets. From the paper:

Despite many similarities, there are significant observed differences between Uranus and Neptune: while Uranus is tilted and has a regular set of satellites, suggesting their accretion from a disk, Neptune’s moons are irregular and are captured objects. In addition, Neptune seems to have an internal heat source, while Uranus is in equilibrium with solar insulation. Finally, structure models based on gravity data suggest that Uranus is more centrally condensed than Neptune. We perform[ed] a large suite of high-resolution SPH simulations to investigate whether these differences can be explained by giant impacts.

For Uranus, we find that an oblique impact can tilt its spin axis and eject enough material to create a disk where the regular satellites are formed. Some of the disks are massive and extended enough, and consist of enough rocky material to explain the formation of Uranus’ regular satellites.

For Neptune, we investigate whether a head-on collision could mix the interior … We find that massive and dense projectiles can penetrate towards the center and deposit mass and energy in the deep interior, leading to a less centrally concentrated interior for Neptune.

We conclude that the dichotomy between the ice giants can be explained by violent impacts after their formation.

As another team member, Alice Chau, noted:

It is often assumed that both planets formed in a similar way.

But these results show that their formations – or at least their very early history – were not so similar as first thought.

Neptune and its largest moon, Triton, whose orbit is highly inclined. Triton’s orbit suggests it was captured by Neptune’s gravity. Meanwhile, the moons of Uranus likely formed in the same disk of gas and dust that Uranus did.

Image via NASA/ JPL/ USGS/ Astronomy.

In one scenario, where Uranus and Neptune start off as being more similar, it was found that an impact with a body of one to three Earth masses could explain the differences we see today. If the object just grazed Uranus instead of a head-on collision, the planet’s interior would not be affected but the impact would still be enough to tilt the planet.

Conversely, if Neptune did experience a head-on impact, the collision would have affected the planet’s interior but would not form a disk of debris. This would explain why Neptune doesn’t have any large moons in regular orbits. A large heat flux on Neptune also points to the interior being remixed in a massive collision.

The simulations show how the two planets probably started off being much more similar, but the different kinds of collisions altered them significantly. As team member Ravit Helled said:

We clearly show that an initially similar formation pathway to Uranus and Neptune can result in the dichotomy observed in the properties of these fascinating outer planets.

Comparison of the interior structures of the 2 gas giants, Jupiter and Saturn, and the 2 ice giants, Uranus and Neptune. Earth is to scale.

Image via NASA/ Lunar and Planetary Institute.

The results of this study show how random events – like planetary collisions with other large bodies in the early solar system – can decidedly affect the future evolution of a planet. Uranus and Neptune are the worlds we see today because of such events, this study says. What if neither planet had been hit? What if Neptune had just been grazed instead of Uranus? What would these ice giants be like today in such circumstances? We don’t know, but knowing more about how they could have been affected will help scientists better understand the formation of these types of planets, as well as the gas giants like Jupiter and Saturn, and rocky worlds like Earth, Mars, Venus, and Mercury.

With a better understanding of how the planets in our own solar system formed and evolved, we can then also apply that knowledge to the study of worlds in distant solar systems.

• Bottom line: A new study by researchers at PlanetS sheds light on why Uranus and Neptune are similar in some ways, but radically different in others. It seems collisions – early in solar system history – are the key.
• Source: Bifurcation in the history of Uranus and Neptune (the role of giant impacts)
• Via PlanetS

{ https://earthsky.org/ }

10-02-2020 om 23:21 geschreven door peter  

The UFO phenomenon has many aspects that are all increasingly weirder than the last. It is often difficult to ascertain just what we are dealing with, and such accounts can really run the range from the merely odd to the downright absurd. Among all of these reports one can find certain strings of reports that don’t seem to really fit into any particular mold, and definitely one of these was a strange flap of anomalous green fireballs that appeared over a period of a couple of years over New Mexico, in the United States, which are mostly an obscure oddity but which still have never been solved.

The strange phenomena known as the “green fireballs” can best be tracked back to December 5, 1948, when a USAF C-47 transport plane crew was on their way from Lowry Air Force Base, Colorado, to Williams Air Force Base in Chandler, Arizona. It had been a fairly routine flight until they got near Las Vegas and observed an eerie green light described as a “green ball of fire” illuminating the sky to the west of the city, followed by another not long after. At around the same time, another plane in the vicinity reported the same thing, describing it as pale green with a pale green trail, and saying that the light seemed to be coming towards them, fast enough that they took evasive maneuvers to avoid a collision. The crew at first thought it might be a meteorite but they dismissed this due to the fact that the object was too low to the ground and not moving fast enough. One pilot would say of the object:

Take a soft ball and paint it with some kind of fluorescent paint that will glow a bright green in the dark… Then have someone take the ball out about 100 feet in front of you and about 10 feet above you. Have him throw the ball right at your face, as hard as he can throw it. That’s what a green fireball looks like.

Image by Steve Baxter

Interestingly, while it was mostly thought that this was clearly a meteorite, when a Dr. Lincoln LaPaz, head of the University of New Mexico’s Institute of Meteoritics was sent to the area where it was believed the object should have fell based on its reported flight path there was no sign of any impact and no trace of a meteorite. On December 8, 1948, sightings of these strange green lights would continue, when a Beech T-7 on its way from Kirkland AFB to Las Vegas when the pilot and co-pilot saw a brilliant green light about 2,000 ft above them, which was headed their way at high speed and with a trajectory described as “flat and parallel to the ground.” The researcher LaPaz would once again step in to investigate and learn that there had been several other sightings of these green balls of light, all of them near the Los Alamos National Laboratory in New Mexico and Sandia atomic-weapons laboratory, as well as at other key military and sensitive installations in the region such as radar stations, nuclear reactors, and fighter-interceptor bases around the country. Why? No one knows.

Making it all rather intriguing was that most of these sightings were being made by trained observers and reliable witnesses such as pilots, weather observers, scientists, intelligence officers and other military personnel, who were unlikely to be making this all up or making mistakes as to what they were seeing. During his investigation LaPaz was also unable to uncover any evidence of meteorite activity, nor that there had been ever any rocket or flare tests in the areas where these sightings were taking place during those time frames. He also was beginning to doubt the meteorite theory by this point, because of the horizontal trajectories of the objects and the fact that green was not considered to be a usual color for meteorites, with him saying of the strange phenomenon:

The fireballs are Kelly green, whereas meteors are red, yellow, blue, or white. A green color could be caused by large amounts of copper, but this element is rarely found in ordinary fireballs. It could also originate from certain man-made atomic fuels. They make no noise. None of the observers of green fireballs, nor persons in the area of the balls, have report any sound whatsoever. Also the fact that they disappear and no fragments have been found on the earth, may be evidence that their flight is controlled.

Sightings of the strange green balls of fire would continue coming in over the coming month, with LaPaz himself seeing one of them on December 12th near Santa Fe that due to its perfectly horizontal trajectory, color, speed, and the way it wobbled convinced him this was no meteor. He would later ascertain that the object had passed directly over the Los Alamos laboratory and had been seen by several other witnesses in the area. A particularly spectacular sighting was made on December 20, when a patrol at Los Alamos observed several luminescent green lights descend rapidly at an angle of 45 degrees, only to then level off and continue on a horizontal pathway out of sight. On this occasion there was even mention made of what looked like an exhaust trail, similar to that of a rocket. Making it more curious is that when these sightings were reported the Air Force was quick to keep it all under wraps, even going as far as to halt the press release on the incident because of “pressure from other agencies also investigating this occurrence.” The story still managed to get out, and in a Feb 29, 1949 edition of the local newspaper Skyliner it was written of the secrecy:

A call to El Paso, Tex., brought official denial from D. K. Brown, head of the Federal Bureau of Investigation district that embraces Los Alamos, that his agency had not been called to deal with the matter. At the information or thought-control office officials indicated that they knew about the recurring green flame in the sky but indicated that it wouldn’t be wise to write about it. Capt. Carroll Tyler, project manager, said simply that all he knew about the lights was rumor — the same rumors that everyone is hearing.

Why was there so much official denial over these sightings? Who knows? Sightings would continue into the next year, when there were more reports into January. One notable account occurred on January 30, 1949, when an extremely bright green fireball was observed over New Mexico by over one hundred witnesses, including trained military personnel, oil workers, aircrew, control tower personnel, all of who described the same thing and noted that the object was completely silent. Sightings would keep on coming in right on into the following year, when pilot Captain A. Harvey and co-pilot Merrick C. Marshall saw a green fireball as they were approaching Albuquerque from Gallup, New Mexico. The Dec. 18, 1950 edition of the Albuquerque Journal would say of the encounter:

The two flyers reported that the light first appeared in the northeast, approximately over Las Vegas. They watched the light for ten minutes, they said, as it moved in the direction of Las Alamos. During that time the “greenish fireball” seemed to circle Los Alamos and then head directly toward Albuquerque. In turning, the light changed from green to a very bright white and passed over and to the rear of their plane — then near Albuquerque — at an estimated speed of over “700 miles an hour.” The time when the light was first sighted was at exactly 11:25 p.m. It remained in view until 11:35. Both pilots are experienced airmen and said it could not possibly have been another plane.

After this the sightings of the green fireballs sort of peter out and we are left to search for answers. Theories have abounded as to what could have caused the 1948-1950 green fireball flap of the Southwest. The meteor theory was largely put to rest by LaPaz, who could find no evidence whatsoever that meteorites were to blame and also pointed out time and time again that the objects displayed very uncharacteristic features for meteorites. Another idea is that it was caused by the phenomenon called ball lightning, which is in itself little understood and entails hovering orbs of electricity that appear and then blink out of existence. Still other ideas are that this was evidence of top secret aircraft or rocket tests, fallout-debris clouds associated with top-secret atomic testing, or Soviet spy technology, which might explain why they were always seen near these government installations. Of course there is also the idea that these were UFOs or even probes dropped from larger alien spacecraft. What was at the heart of the deluge of green fireball accounts reported by so many during this time span? Was this meteors, atmospheric phenomena, or visitors from another world? We didn’t know then, and we don’t know now. It remains a mystery.

{ https://mysteriousuniverse.org/ }

10-02-2020 om 22:48 geschreven door peter  

10-02-2020 om 20:38 geschreven door peter