What’s 426 feet wide, travels 55,000 miles per hour, and can sneak up on you before you know it?

Apparently 2019 OK, a potentially deadly asteroid which remained unnoticed until within 24 hours of its near-miss with Earth earlier this year, according to newly released emails.

The story was reported by BuzzFeed, who obtained internal NASA emails about the incident via Freedom of Information Act Request.

“Spotted just 24 hours before a relatively narrow miss with Earth, the incident reveals holes in NASA’s surveillance network to observe incoming space rocks, ” BuzzFeed writers Dan Vergano and Jason Leopold reported. Apparently the object was first observed by a Brazilian observatory, which notified the U.S. space agency.

The fact that 2019 OK passed within just 40,500 miles of Earth is certainly a wakeup call. However, does the news mean it’s time to appoint new experts to sit at the helm of Earth’s planetary defense systems?

Not quite.

Asteroid detection is a burgeoning field, not only due to advancements in science and technology, but mainly out of necessity. In the eventual sense, a space object large enough to be able to cause widespread damage will strike the Earth–it’s not a matter of if, but simply one of when.

If we are to be able to prepare for this eventuality at all, Earthlings have no option but to find the best ways of detecting potential threats of this kind before they happen.

While the fact that 2019 OK managed to sneak up on us is legitimately concerning, let’s not forget the fact that it was spotted. Also, in a similar set of circumstances that occurred back in June, the University of Hawaii managed to detect a car-sized asteroid with the help of its ATLAS and Pan-STARRS survey telescopes, which are located near Puerto Rico.

“The 4-meter diameter asteroid, named 2019 MO, was observed four times in a span of 30 minutes by the ATLAS Maunaloa facility, just after midnight Hawaiʻi time on the morning of Saturday, June 22,” a press release from the university stated. “At that time, the asteroid was only 500,000 km from Earth – or 1.3 times the distance to the Moon.”

Part of what makes these “near misses” so disturbing is that we’re seeing them at all. As our asteroid detection capabilities continue to improve, what we’re actually seeing is a better success rate at spotting these objects, whereas in the past they might not have been seen at all.

The really sobering idea is to think of how many more times in the past there were larger–or closer–objects that sped past Earth without us having so much as an idea.

According to NASA, “At the start of 2019, the number of discovered near-Earth asteroids totaled more than 19,000. An average of 30 new discoveries are added each week.”

That’s a lot of space rocks being detected.

In fact, by October 2016, NASA had reached a landmark number of 15,000 asteroids detected:

“The 15,000 milestone, reached on October 13, 2016, marked a 50 percent increase in the number of known near-Earth asteroids since 2013, when discoveries reached 10,000 in August of that year. More than 95 percent of these objects were discovered by NASA-funded surveys (primarily using ground-based telescopes) since 1998, when NASA initially established its Near-Earth Object Observations Program and began tracking and cataloguing them.”

It’s easy to see why people would be worked up about news of a “near-miss” like what happened with 2019 OK. However, rather than a failure on part of NASA and other space agencies around the world, if anything, it’s a clear indication that our planetary defense science is steadily improving.

Maybe we need to cut them some slack in the meantime; as these innovative defense systems continue to improve, they may also one day save the world and all life as we know it.

{ https://mysteriousuniverse.org/ }

23-09-2019 om 14:43 geschreven door peter  

“The InSight fluxgate magnetometer has detected magnetic pulsations on the surface of Mars for the first time. The observations have implications to the wave sources in the induced magnetosphere and whether and how these waves can reach the surface.”

That type of report coming from your local police would cause some concern. Coming from the EPA or the military, it would be a cause for worry. Coming from Mars … it’s a mystery, but it’s definitely a sign of job security for space engineers. At the latest joint meeting of the European Planetary Science Congress and the American Astronomical Society, a NASA gave a presentation on findings by the Mars InSight lander, including the startling revelation that it has been detecting mysterious long pulsations at the Martian midnight. In addition, another presentation reveals that it found strange electrical signs that may be coming from a 2.5-mile-thick layer under the surface that just might be water. Finally, the InSight and its engineers are celebrating because the lander received an Emmy! Wait, what?

Artist depiction of InSight on the Martian surface

(NASA/JPL)

“The nighttime continuous pulsations found by IFG are unexpected because they are distinct from what are typically observed on the Earth’s surface at the same local time. On the other hand, we have not found the Mars counterparts for many types of geomagnetic pulsations well known in Earth studies. We speculate that the observed magnetic pulsations by InSight to date are associated with fluctuations in the induced magnetotail and on the magnetospheric boundary. Under this scenario, the distinct field and plasma environment at Mars raises interesting questions about how these oscillations propagate through the magnetosphere and ionosphere and reach the surface.”

IFG is the InSight FluxGate, the magnetometer measuring the strength and variations of the surface magnetic field at the InSight landing site on the planet’s equator. The National Geographic story on the conference highlights the importance of InSight providing for the first time a surface analysis of Martian magnetism, which will help scientists determine why Mars lost its protective magnetic and perhaps reveal some warning signs as to if and when Earth might lose its own field. And why do these pulses happen at midnight?

National Geographic covered the second big story from InSight – it picked up magnetic signals from beneath the Martian surface that resemble those on Earth that indicate the presence of water … lots of water. That would bean that somewhere no deeper than 62 miles (100 km) is an aquifer or perhaps even a layer of water that can be drilled to from anywhere on Mars. Unfortunately, InSight’s drill only reaches 16 feet, so the first Martian well belongs to a future probe. If InSight is correct, it won’t need a diving rod.

What about the Emmy?

Oh, yeah. In a special presentation prior the big Emmy Awards show, the Academy of Television Arts & Sciences gave NASA the Outstanding Original Interactive Program award for its coverage of the Insight Lander’s entire life from conception to landing and beyond, using TV, social media and other methods to keep the world informed and involved with this exciting project.

When does the InSight show come on?

“Congrats to those who contributed to the news, web, education, television and social media coverage of this landing on the Red Planet.”

Does it sound like NASA Administrator Jim Bridenstine is more excited about the Emmy than InSight’s discovery of mysterious midnight magnetic pulses and a potential planet-wide water supply? Of course he is! InSight is never coming back to Earth so he gets to keep the statue in his office.

Way to go, InSight!

{ https://mysteriousuniverse.org/ }

23-09-2019 om 14:29 geschreven door peter  

What started off as a joke had about 2 million people pledging to “Storm Area 51” this weekend, and even after the event was cancelled, authorities were still worried that tens of thousands of people may still show up at the gates of the highly guarded Area 51 Air Force base. In total, approximately 3,000 people showed up to the several alien-themed events that took place in the desert region, not far from the base.

With the “storm” weekend finally finished, a surprisingly low amount of visitors gathered at the gate to the base in the early morning hours of September 20^th. Law enforcement officers blocked the road around a mile away from the gate and approximately 150 people walked the remainder of the way up to the back gate of Area 51. Around a dozen officers were present at the gate, as well as an officer with a police dog just in case anyone attempted to get a closer look at the base. At one point, around 20 people in the crowd acted as if they were going to “storm” the gates while the song “Final Countdown” played in the background, but everyone started laughing and nobody ended up “storming”.

A total of five people were arrested – three people (two males and one female) were arrested for trespassing; one person was arrested for indecent exposure for urinating near the gate to Area 51; and one was taken into custody for an alcohol-related incident.

As for the festivities, one event was a lot more successful than the other. “Storm Area 51 Basecamp”, which took place at the Alien Research Center in Hiko, was cancelled after just 500 people showed up on the first day. Keith Wright, who organised the event, said that they had expected 5,000 people to show up. “We put on a safe event for people that showed up,” he said, adding that they had to cancel it because “it costs tens of thousands of dollars to staff each day.”

“Alienstock” seemed to have been a much bigger success. Connie West, who runs the Little A’Le’Inn motel in Rachel, said that “This is the most fabulous time,” and “I’m just so grateful that people came.” The several thousand travelers who were camping on the grounds of the motel and in surrounding areas, were apparently really enjoying all of the musical talent West had brought in for the festivities.

In other news, the US military has issued an apology after posting a tweet that suggested that UFO enthusiasts should be worried that a B-2 nuclear-capable bomber was ready to protect the secrets of Area 51. The Defense Visual Information Distribution Service (or DVIDS) tweeted a photo of a B-2 stealth bomber with a very stern warning that read, “The last thing #Millennials will see if they attempt the #area51raid today.”

All in all, it was a pretty quiet weekend considering that just a few weeks ago, the event was still scheduled to happen with around two million people pledging to storm the base. You can see some pictures here from the “storm” weekend.

An attendee is detained after briefly physically crossing a security line, as people gathered to “storm” Area 51.

Attendee Daniel Rodriguez wears at tinfoil hat as he and other Alien hunters gathered to “storm” Area 51 at an entrance near Rachel, Nevada.

Getty

Attendees depart after gathering to “storm” Area 51 at an entrance to the military facility.

Attendee Ellie Urquhart walks past a security line as people gather to “storm” Area 51.

Members of law enforcement stand near barb wire, as people gathered to “storm” Area 51, at an entrance to the military facility near Rachel, Nevada on September 20, 2019.

Attendees discuss with guards as they gather to “storm” Area 51.

{ https://mysteriousuniverse.org/ }

23-09-2019 om 14:18 geschreven door peter  

The idea that unknown extraterrestrial beings are visiting the Earth for hidden purposes is something to think about.

Yet, if the following cases are to be believed, then that may very well be precisely what is happening.

Whilst it is terrifying to consider the intentions of alien beings who possibly observe us, it is even more frightening to consider how those they are tampering with are the very people we rely on to keep us safe.

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

23-09-2019 om 12:40 geschreven door peter  

Statue Found In Center Of Crater On Mercury, NASA Source. UFO Sighting News.

Date of discovery: 2004
Location of discovery: Planet Mercury
NASA source:

•  https://photojournal.jpl.nasa.gov/catalog/PIA02420
  

Guys, I found this statue with a cat like face and ears way back in 2004, but the 1.5mb size high detail photo was soon taken down by NASA. NASA took the photo back in 2000 and when I found it in 2004, Youtube still didn't exist and I hadn't made my UFO website yet...so it was lost forever. However I found it again in a much smaller size photo on a NASA site. So, please check out my video below to learn its size. It will blow your mind! 
Scott C. Waring

{ https://www.ufosightingsdaily.com/ }

23-09-2019 om 12:33 geschreven door peter  

Aliens visiting? Crashed UFO on Mars and one hovering over navy base in California spotted

The search for alien life has been going on for years and those involved in alien hunting or UFO hunting have many a times, come close enough to provide evidence justifying it.

{ https://zeenews.india.com/tags/sci-tech.html }

23-09-2019 om 12:29 geschreven door peter  

Silvies Valley Ranch

The five dead bulls were found on July 30 and 31, in a wooded area about 15 miles from U.S. 395, the nearest major road. Their genitals and tongues had been cleanly removed.

There are a number of things most cattle mutilation stories have in common. They generally happen at night. The cuts are surgically precise. There’s no blood. And they often happen in groups across a number of farms or ranches in an area. That was the case again recently in Oregon and Queensland, Australia, where multiple mysterious cattle mutilations were discovered in multiple locations. Both sets of incidents have one more thing in common – local law enforcement can’t solve the cases and the cattle owners are blaming … aliens!

“A lot of people lean toward the aliens. One caller had told us to look for basically a depression under the carcass. ‘Cause he said that the alien ships will kinda beam the cow up and do whatever they are going to do with it. Then they just drop them from a great height.”

Deputy Dan Jenkins of the Harney County Sheriff’s Office in Burns, Oregon, is one of those frustrated law enforcement officials. He told Oregon Public Radio (OPR) that he investigating the deaths this summer of five young purebred bulls at the massive Silvies Valley Ranch. He’s heard the stories of other mutilations of young bulls at a ranch in Pendleton and Princeton, both cities in eastern Oregon. Andie Davies in Princeton told OPR that her son, a butcher, was amazed at how clean the killer’s cuts were and Andie herself was baffled by the fact that there were no tracks – footprints, tires, horses, animals – around the fresh, mutilated corpse. Who – or what – is able to traverse this rough terrain to find, kill and mutilate these bulls without leaving a trace of their presence?

Where are the tracks?

“In the last three months we have lost 10 heads and five of them have definitely been under strange circumstances. About three weeks ago my husband was working near the river and noticed a dead cow. He realized the ubre was gone. At first we thought of a dog, but then we saw an ear removed and a circle around the muzzle where the tongue had been removed. Definitely not a person, whether it’s a sophisticated robot or aliens, we just don’t know.”

Down under at the Cloverly Station ranch near Mackay in Queensland, owner Judy Cook is just as baffled and ready to blame aliens or robots. “Ubre” is Spanish for udder, but there are other mysterious circumstances surrounding the multiple cattle mutilations that Cook and her husband have found on their remote ranch – which cannot be accessed by land without someone noticing it.

“It’s an hour’s drive from here and no one gets out without driving straight through the house. There were absolutely no bands, no blood, nothing. It’s amazing to think that there was no blood, no way to cut something with a knife so cleanly. The problem is that nothing approached and ate it; the dogs or the pigs, nothing really wants to take it.”

That’s another common trait of unsolved cattle mutilations – other animals, even scavengers, often don’t touch the corpses. Cook doesn’t want to sound like another angry rancher thinking more about the profits lost than finding what or who could have performed these cattle atrocities, so she’s consulted veterinarians, including one in the U.S. who has investigated similar cases, and they agree that even skilled large animal surgeons with the latest equipment could not make such precise cuts.

In the U.S., a map of cattle mutilations somewhat matches a map of UFO sightings along the 37th parallel – the so-called UFO Highway. However, eastern Oregon is a long way from there. It’s Bigfoot country, but a Venn diagram of Bigfoot sightings and mutilations wouldn’t have many in the overlapping part. And there’s no Bigfoot in Queensland. (Or is there?) Have aliens with a taste for fried ubre expanded their territory?

I don’t care how far it is. I’m pregnant and I have a craving for ubre.

Cattle mutilations are easy to blame on wolves, coyotes, humans – rustlers, people conducting strange rituals, etc. – and other creatures. Those owners tasked with protecting the rest of the herd and law enforcement officers trying to solve the mysterious crimes continue to be baffled and find it increasingly difficult to blame conventional causes. That’s so many are moving to believe what Andie Davis says:

“Definitely not a person, whether it’s a sophisticated robot or aliens, we just don’t know.”

{  http://reverenceparanormal.stevesorrellphotography.com/ }

23-09-2019 om 12:08 geschreven door peter  

US Moon Landing Hopefuls Watch Silent India Lander — and Learn

By Meghan Bartels 

An artist's depiction of the Chandrayaan-2 lander, Vikram, preparing to alight on the lunar surface. The procedure occurred on Sept. 6, 2019, but appears to have gone wrong, with the Indian space agency losing contact with the lander late in the maneuver.

(Image: © ISRO)

As India attempted a daring moon landing last week — and in the wake of the apparent crash of its lander — NASA and U.S. companies have watched for any insights relevant to their own upcoming moon shots.

India's Chandrayaan-2 was an ambitious three-part mission, with an orbiter settled into circling the moon and a lander and rover that were meant to make a soft touchdown on Sept. 6. But late in the landing process, the Vikram lander went silent, and the Indian Space Research Organisation (ISRO) is running out of time to reconnect with the robot. If it cannot, the incident will mark the second lunar lander lost this year, joining Israel's Beresheet mission. For the U.S., which hasn't attempted to land on the moon since the Apollo program but wants to again soon, it's a stark reminder of the difficulty of spaceflight.

"For us from a management perspective, we just know this is hard," Camille Alleyne, deputy manager for the Commercial Lunar Payload Services (CLPS) program at NASA's Johnson Space Center, said during a panel yesterday (Sept. 12) at a symposium held in Huntsville, Alabama. The CLPS program wants to purchase landing services from U.S. companies to ferry science instruments. "It's clear that our contractor pool has a steep challenge on their hands."

• Related: India's Chandrayaan-2 Mission to the Moon in Photos

Currently, two U.S. companies are taking part in the first round of CLPS missions, which are meant to land in 2021: Astrobotic and Intuitive Machines. Sharad Bhaskaran, mission director for Astrobotic, was also on the panel and had only praise for both Chandrayaan-2 and its Israeli predecessor.

"I think both the SpaceIL and the ISRO missions were huge successes," Bhaskaran said. "Our challenge is to learn from those missions, understand what happened, make sure that we don't make the same mistakes. If there are design changes we can make at this stage, we will make those. But I felt personally those were huge successes."

ISRO has said that even without a successful landed component, the Chandrayaan-2 mission has completed between 90% and 95% of its objectives. And the mission will likely produce plenty of science to come through the orbiter, judging by the success of its predecessor, which carried the instrument that identified water ice below the lunar surface inside dark craters near the south pole. 

NASA's own moon orbiter may provide vital information for both ISRO and future American lunar landing attempts. The Lunar Reconnaissance Orbiter, which has been circling the moon since 2009, is scheduled to fly over the Vikram lander's targeted touchdown site on Sept. 17.

The spacecraft's photos could help ISRO diagnose the current status of the lander and aid the agency's continuing efforts to establish contact with it. In the wake of Beresheet's crash in April, the LRO also photographed that site.

But the LRO was also close enough during Vikram's landing attempt to gather data about the maneuver using its Lyman-Alpha Mapping Project instrument, Jay Jenkins, program executive for the Office of Exploration at NASA's Science Mission Directorate, said during the panel.

"As a matter of fact, during the descent of Chandrayaan-2, the LAMP instrument was observing the changes in the exosphere as a result of the rocket effluence coming down," he said. The exosphere is the moon's very thin would-be atmosphere; the rockets would have been attempting to slow the spacecraft enough for a soft landing. "So we're really eager to see how those observations turn out."

With Chandrayaan-2, India was attempting a feat that NASA has not tried in decades; its last soft landing on the moon was in 1972. Since then, the agency has concentrated on sending landers and rovers to Mars instead. And given NASA's focus on enlisting the commercial space industry in its endeavors, that leaves a tantalizing opportunity for U.S. companies to dream of succeeding at what Israel and India could not quite execute.

"I think those were very strong motivators for us to continue our mission and to be the first successful American landing since Apollo," Bhaskaran said.

•  India's Chandrayaan-2 Spacecraft Snaps Its First Picture of the Moon 
•  Amazing Moon Photos from NASA's Lunar Reconnaissance Orbiter 
•  Stunning Photos Show Earth from India's Spacecraft Headed to the Moon 

Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook. 

{ https://www.space.com/ }

23-09-2019 om 11:36 geschreven door peter  

1st Color Photo of Interstellar Comet Reveals Its Fuzzy Tail

23-09-2019 om 11:16 geschreven door peter  

2 Asteroids Will Harmlessly Fly By Earth This Weekend, But NASA Will Wave Hello Anyway!

23-09-2019 om 00:51 geschreven door peter  

22-09-2019 om 22:42 geschreven door peter  

Artist’s concept of an object called S0-2 orbiting our Milky Way’s supermassive black hole. Astronomers tracked this object for years, hoping to catch it falling over the hole’s event horizon. It did not fall in, but its close approach in 2018 might be one reason for the black hole’s growing appetite now.

Image via Nicolle Fuller/National Science Foundation.

UCLA astronomers announced on September 11, 2019, that, last May, they caught the supermassive black hole at the center of our Milky Way galaxy having an unusually large meal of interstellar gas and dust. They caught the feast on May 13 (although of course it happened some 25,000 years ago earlier, since the center of the galaxy is about 25,000 light-years away). What they saw was this. The black hole – called Sagittarius A*, pronounced Sagittarius A-star – became extremely bright in May 2019, growing 75 times as bright for a few hours. Yet, as of now, the researchers don’t yet understand why. Why did the area just outside the black hole’s event horizon – its point of no return – suddenly become brighter? What did it ingest, and why at that time?

Astronomer Tuan Do is lead author of new research describing this event, published September 11 in Astrophysical Journal Letters. He also produced the timelapse in the tweet below, which depicts the brightness changes at Sgr A*. Andrea Ghez, of the UCLA Galactic Center Group, is co-senior author on the new paper. She said:

We have never seen anything like this in the 24 years we have studied the supermassive black hole. It’s usually a pretty quiet, wimpy black hole on a diet. We don’t know what is driving this big feast.

In a statement, the researchers also said they:

… analyzed more than 13,000 observations of the black hole from 133 nights since 2003. The images were gathered by the W. M. Keck Observatory in Hawaii and the European Southern Observatory’s Very Large Telescope in Chile. The team found that on May 13, the area just outside the black hole’s ‘point of no return’ (so called because once matter enters, it can never escape) was twice as bright as the next-brightest observation.

They observed large changes on two other nights this year; all three of those changes were ‘unprecedented,’ Ghez said.

They said the brightness surrounding the black hole always varies somewhat, but the extreme variations in brightness observed this year left them “stunned.”

So what is going on?

In an absolute sense, the increased brightness on a few nights in 2019 can be explained by radiation from gas and dust falling into the black hole. One hypothesis about the increased activity is that when a star called S0-2 made its closest approach to the black hole during the summer 2018, it launched a large quantity of gas that reached the black hole this year. Tuan Do, the study’s lead author, said:

The first image I saw that night, the black hole was so bright I initially mistook it for the star S0-2, because I had never seen Sagittarius A* that bright. But it quickly became clear the source had to be the black hole, which was really exciting.

Another possibility involves a bizarre object known as G2, which is most likely a pair of binary stars, which made its closest approach to the black hole in 2014. It’s possible the black hole could have stripped off the outer layer of G2, Ghez said, which could help explain the increased brightness just outside the black hole.

Morris said another possibility is that the brightening corresponds to the demise of large asteroids that have been drawn in to the black hole.

The question for astronomers is, what does this activity mean? Is it simply an extraordinary singular event, or is it a precursor to significantly increased activity for Sgr A*? Mark Morris, UCLA professor of physics and astronomy, is another author on the paper. He said:

The big question is whether the black hole is entering a new phase – for example if the spigot has been turned up and the rate of gas falling down the black hole ‘drain’ has increased for an extended period – or whether we have just seen the fireworks from a few unusual blobs of gas falling in.

The team has continued to observe the area. They say they’ll try to settle the question based on what they see from new images. Ghez said:

We want to know how black holes grow and affect the evolution of galaxies and the universe. We want to know why the supermassive hole gets brighter and how it gets brighter.

By the way, these astronomers commented:

The black hole is some 26,000 light-years away and poses no danger to our planet. Do said the radiation would have to be 10 billion times as bright as what the astronomers detected to affect life on Earth.

Astrophysical Journal Letters also published a second article by the researchers, describing speckle holography, the technique that enabled them to extract and use very faint information from 24 years of data they recorded from near the black hole.

Ghez’s research team reported July 25 in the journal Science the most comprehensive test of Einstein’s iconic general theory of relativity near the black hole. Their conclusion that Einstein’s theory passed the test and is correct, at least for now, was based on their study of S0-2 as it made a complete orbit around the black hole.

Ghez’s team said it:

… studies more than 3,000 stars that orbit the supermassive black hole. Since 2004, the scientists have used a powerful technology that Ghez helped pioneer, called adaptive optics, which corrects the distorting effects of the Earth’s atmosphere in real time. But speckle holography enabled the researchers to improve the data from the decade before adaptive optics came into play. Reanalyzing data from those years helped the team conclude that they had not seen that level of brightness near the black hole in 24 years.

Ghez said:

It was like doing LASIK surgery on our early images. We collected the data to answer one question and serendipitously unveiled other exciting scientific discoveries that we didn’t anticipate.

Twitter Talk: Flashing Supermassive Black Hole from Keck Observatory on Vimeo.

• Bottom line: UCLA astronomers announced on September 11, 2019, that – in May – they caught the supermassive black hole at the center of our Milky Way galaxy having an unusually large meal of interstellar gas and dust. Why did the area just outside the black hole’s event horizon – its point of no return – suddenly become dramatically brighter? What did it ingest, and why at that time?
• Source: Unprecedented Near-infrared Brightness and Variability of Sgr A*
• Via UCLA

{ https://earthsky.org/ }

22-09-2019 om 22:23 geschreven door peter  

Posted by Paul Scott Anderson in SPACE 

It was exciting last week when scientists announced water vapor in a super-Earth’s atmosphere. But, even as the announcement came, other scientists were cautioning that the planet – K2-18b – is probably less like a super-Earth and more like a mini-Neptune.

Artist’s concept of K2-18b, as well as another planet in this system, K2-18c, with the parent star, a red dwarf, in the background.

Image via Alex Boersma/iREx.

A couple of days ago, EarthSky reported that for the first time ever, water vapor had been detected in the atmosphere of a potentially habitable super-Earth exoplanet. We weren’t alone in our report. As might be expected, the finding received a lot of attention from media. But, it turns out, that the story might not be quite as first reported and was mis-characterized to some extent.

The discovery was outlined in two different papers, the first one published on arXiv on September 10, 2019, and the second in the peer-reviewed journal Nature Astronomy on September 11, 2019.

The papers detail the finding of water vapor in the atmosphere of K2-18b, an exoplanet in the habitable zone of its star – where temperatures could allow liquid water to exist – 110 light-years from Earth. It’s accurate that this is the first time that water vapor has been identified in the atmosphere of a smaller exoplanet (non-gas-giant) in the habitable zone of its star, but soon after the announcement, many planetary scientists critiqued how the discovery was covered in media and social media.

The water vapor detection itself is confirmed, but there is a lot of debate as to just what kind of planet K2-18b actually is, and how habitable it may be (or not).

Another artist’s concept of super-Earth K2-18b. Scientists have detected water vapor in its atmosphere, but is it habitable? Most scientists say it’s unlikely.

Image via ESA/Hubble, M. Kornmesser/UCL News.

Some scientists, including in the Nature Astronomy paper, have referred to the planet as a super-Earth. A super-Earth is larger than Earth but smaller than Neptune – typically up to about a maximum of twice the size of Earth – and many have been discovered already. Most are thought to be rocky, like Earth, but there is a transition point – starting about 1.6 to 2 times Earth’s radius – where a planet can become a mini-gas-giant, or a mini-Neptune as they are usually called. They are larger than super-Earths, but still smaller than Neptune. Most scientists now consider K2-18b to be a mini-Neptune, not a super-Earth, with a deep atmosphere of hydrogen and/or helium, and possibly no solid surface at all.

K2-18b has a radius of about 2.7 times that of Earth, and a mass about nine times that of Earth. While some scientists would still consider that to be a possible super-Earth, most, it seems, would classify it as a mini-Neptune. All of this can be a bit confusing.

The 2017 study previously linked to considered that K2-18b might be either large and rocky or covered with water and/or ice. But that study didn’t account for atmospheric constraints, only mass and radius. As exoplanet scientist Erin May told me on Twitter:

My PhD partially focused on the distinction between these classes of planets. Many studies show that it’s extremely difficult to make a planet > than 2 Earth-radii without a large atmosphere. Mass & radius (density) alone are actually not very useful here. I’d also like to point out that from mass and radius alone, this planet should have never been considered a super-Earth. I think there’s a tendency to throw this term around because it’s more “exciting”, but we as astronomers need to keep our terminology straight.

Néstor Espinoza, an astronomer at the Max Planck Institute for Astronomy (MPIA), also told me:

If you believe the water feature, you have to believe it is an H/He dominated atmosphere so yes. And the source you cite is not “outdated” – at that time we just didn’t have atmospheric constraints, only mass and radius. Also: the very fact that we see a water feature *implies* a H/He dominated atmosphere. There is no way around it.

There is a good Twitter thread about all this here, from Jessie Christiansen, a research scientist at NASA Exoplanet Science Institute (NExScI):

Dr. Jessie Christiansen

✔@aussiastronomer

GUYS. Two independent announcements today of the same thing: We have found water vapor in the atmosphere of a planet called K2-18 b!

BUT WAIT?

WHAT DOES IT MEAN?

• 483

9:32 PM - Sep 11, 2019

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• 182 people are talking about this

Also from Nature correspondent Alexandra Witze:

Alexandra Witze

✔@alexwitze

Some news today about K2-18b, a small planet 110 light-years from Earth. Hubble has spotted water vapor & possibly clouds in its atmosphere. https://twitter.com/NatureNews/status/1171831032989044736 …

Nature News & Comment

✔@NatureNews

The Hubble Space Telescope spies a rare glimpse of water in the atmosphere of an exoplanet that isn't much bigger than Earth. https://go.nature.com/2LsFk2E 

• 193

7:02 PM - Sep 11, 2019

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Alexandra Witze

✔@alexwitze

 · Sep 11, 2019

Replying to @alexwitze

In Nature Astronomy, using the Hubble data from Benneke's observing proposal, Tsiaras et al also report a water vapor detection on K2-18 b.

Alexandra Witze

✔@alexwitze

The planet is more of a mini-Neptune than a super-Earth: it's got a thick hydrogen atmosphere and if you want to find the water you'd have to go ballooning. But, the work is pushing the limits of understanding these alien worlds and how like (or unlike) Earth they may be.

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7:07 PM - Sep 11, 2019

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And another thread, from Marina Koren at The Atlantic:

Marina Koren
✔@marinakoren

1/ A thread about the big exoplanet news that was announced today, which—to be perfectly honest—was challenging for me to parse and report.. https://www.theatlantic.com/science/archive/2019/09/water-vapor-explonet-atmosphere/597850/ …

An Exoplanet Like No Other Yet Found

K2-18b probably can’t host life as we know it, but it orbits in a cosmic sweet spot where water vapor in the atmosphere could turn into liquid.

theatlantic.com

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9:50 PM - Sep 11, 2019

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So what about habitability? Since the planet is considered – by most scientists – to now be a mini-Neptune, this lowers the chances significantly. Water vapor itself, or even rain (as still considered possible in this planet’s atmosphere), is great, but life-as-we-know-it requires a rocky surface/interior for chemical nutrients, and bodies of liquid water. There may indeed be planets out there with life forms in only a gaseous atmosphere, but for Earth-kind of life at least, K2-18b would seem to be ill-suited for this.

There has been a lot of debate over whether K2-18b is a super-Earth or mini-Neptune. Most scientists now agree that it is a mini-Neptune, making habitability much less likely.

Image via Patterson Clark/Washington Post/Quora.

Finding evidence for water vapor on a distant exoplanet in its star’s habitable zone is exciting, but is not in itself proof of habitability. There are many factors that need to be considered, including composition of the planet and its atmosphere. However, K2-18b is the smallest exoplanet so far found to have water vapor in its atmosphere, which is a good sign: it supports the contention of scientists that even smaller planets with water vapor and/or liquid water will be found, worlds that are more Earth-like in terms of both size and composition. Upcoming space-based telescopes such as the James Webb Space Telescope (JWST) will be able to study the atmospheres of planets like this, and smaller, in greater detail than ever before, and even search for biosignatures, which could be evidence for life.

• Bottom line: The exoplanet K2-18b does have water vapor in its atmosphere, but the planet itself is probably very un-Earth-like.
• Source: Water vapour in the atmosphere of the habitable-zone eight-Earth-mass planet K2-18 b
• Source: Water Vapor on the Habitable-Zone Exoplanet K2-18b
• Via UCL News

{ https://earthsky.org/ }

22-09-2019 om 22:06 geschreven door peter  

{ https://sputniknews.com/ }

22-09-2019 om 21:44 geschreven door peter  

SpaceX Seeks Property Buyouts Near Starhopper Launch Site in Texas: Report

By Elizabeth Howell 

SpaceX launched its Starhopper rocket prototype on its highest flight ever on Aug. 27, 2019. The reusable hopping rocket flew from one pad to the other, with a targeted 500-foot (150 meters) ceiling at SpaceX's South Texas test site near Boca Chica Village.

(Image: © SpaceX)

SpaceX wants to buy out the properties of residents in a community located only a few miles away its Starhopper launch site in south Texas, according to a report.

The company's Starhopper flights made headlines this summer as the rocket prototype flew as high as 500 feet (about 150 meters) in altitude. Starhopper fits in well in with SpaceX's Mars exploration plans, as Starhopper is supposed to be an early prototype for the Starship vehicle that SpaceX hopes will bring people to the Red Planet in the coming decades. 

But that testing has also produced an unintentional 100-acre brush fire and even explosion warnings in the launching region, which lies nearby the tiny hamlet of Boca Chica, according to Business Insider. 

So, SpaceX sent buyout offers to at least 10 households in the community — which has a predominantly elderly population of only about 20 people — saying the company is concerned about "increased disruption to Boca Chica residents and our commitment to complying with public health and safety guidelines," according to the letter, which is written with SpaceX letterhead.

• Related: SpaceX's Starship and Super Heavy Mars Rocket in Pictures

"We did not anticipate that local residents would experience significant disruption from our presence," SpaceX explains of its reasoning to use Cameron County as a potential spaceport location. "However, it has become clear that expansion of spaceflight activities, as well as compliance with Federal Aviation Administration and other public safety regulations, will make it increasingly more challenging to minimize disruption to residents of the village."

SpaceX is offering each household a fixed buyout price of three times the appraised property value, saying that it favors giving an identical deal to residents because it is "the fairest approach." The letter, which is dated Thursday (Sept. 12), adds that the offer is good for two weeks — or until Sept. 26.

To anyone who will accept the offer, SpaceX also plans to give those residents exclusive access to more Starship development events, through "future private VIP launch viewing events that are unavailable to the public."

A few residents told Business Insider they have no interest in accepting the buyout. For example, Maria Pointer, who runs a Facebook group about SpaceX that generally supports its work, said that the company does not understand that most residents cannot afford to buy properties nearby, even with SpaceX's offer to triple property values.

"They need to understand that most of this community has very limited income," she said. "We want to move on, just give us what we need to move on. I'm not going to go to a trailer or an apartment. I gave my life to this property. I gave it everything I had. Nobody else wanted to tame it."

SpaceX did not immediately respond to a Business Insider request for comment. On Sept. 28 — two days after the offer deal closes — the company reportedly plans to give a presentation in an area nearby to provide an update about the Starship development program.

Since SpaceX is not a publicly owned company, outsiders can only get a partial view of its financial situation. The company's valuation was appraised at $33.3 billion in May, according to CNBC. SpaceX is engaged in multiple spaceflight projects, including Starship, creating a vast network of 5G satellites called Starlink, developing a Crew Dragon commercial crew vehicle for NASA, making cargo runs to the International Space Station, and hefting satellites using its Falcon 9 and Falcon Heavy rockets.

• SpaceX's Next Starship Prototype Taking Shape (Photos)
• SpaceX Is Building a 'Starship' Rocket Prototype in Florida, Too
• SpaceX's Next Starship Prototype Launch Will Be a 12-Mile-High Test Flight

Follow Elizabeth Howell on Twitter @howellspace. Follow us on Twitter @Spacedotcom and on Facebook.  

{ https://www.space.com/ }

22-09-2019 om 21:10 geschreven door peter  

Ruim 2.000 ‘UFO-gelovers’ bijeen, maar bestorming geheime Area 51 blijft uit - HLN.be

Bron: AD.nl

Op het zwaarbewaakte terrein zouden stiekem buitenaardse ruimteschepen en hun bemanning verstopt zijn. De initiatiefnemer van het evenement had mensen opgeroepen het complex gisteren te bestormen. In totaal zegden online ruim 2 miljoen mensen toe, maar in realiteit kwamen ‘maar’ ongeveer 2.300 mensen opdagen, aldus lokale media. Een bestorming bleef uit.

Lees ook

“Ufo’s met aliens? Ultrageheime projecten van grootmachten, ja”

“Mensen droegen gekke kostuums bij de ingang van de basis”, zei een bezoeker. “Waarom zou je dat willen missen? Het is een ervaring die je maar één keer in je leven meemaakt.” Sommige feestgangers droegen ruimtepakken en maskers van buitenaardse wezens. Ook hadden sommigen spandoeken bij zich.

De festiviteiten zijn niet uitgelopen op een chaos, iets waar de Amerikaanse autoriteiten op voorhand bang voor waren. Zij waarschuwden mensen juist níet naar Area 51 te komen. Eén vrouw wist de streng beveiligde toegangspoort te passeren en werd tijdelijk vastgehouden, maar ze is inmiddels weer vrijgelaten. Twee bezoekers werden aangehouden voor aanstootgevend gedrag en alcoholmisbruik. “De mensen zijn hier vooral om te kijken wat er aan de hand is”, zei een veiligheidsagent. “Ze komen om plezier te hebben.”

De mysterieuze basis wordt volgens het Amerikaanse leger gebruikt voor het ontwikkelen van geheime militaire projecten. Maar er doen al decennia theorieën de ronde dat de VS op de basis de restanten van een UFO (en haar bemanning) verborgen houdt, en er ook op andere wijze contact onderhoudt met buitenaards leven. In 1947 zou bij de basis een vliegende schotel zijn neergestort. Het gebied is daarom uitgegroeid tot bedevaartsoord voor mensen die in UFO’s en aliens geloven. De weg die naar het gebied leidt, Highway 375, is omgedoopt tot de Extraterrestrial (buitenaardse) Highway.

Storm Area 51

Vanwege een uit de hand gelopen grap verzamelen zich uiteindelijk dus meer dan 2.000 mensen in de woestijn van Nevada, vlakbij Las Vegas. In juli maakte een Amerikaan op facebook het ‘Storm Area 51’-evenement aan om ‘de aliens te gaan zien’. Het motto was ’They Can’t Stop All of Us. Met andere woorden: als we met zoveel mogelijk mensen de basis bestormen, kunnen ze ons niet allemaal tegenhouden. Binnen de kortste keren gaven 2,1 miljoen mensen vanuit de hele wereld aan te komen voor de geplande bestorming op 20 september. Wat het Amerikaanse leger er toe bracht in een officiële verklaring te stellen “iedereen te ontraden de basis te betreden”. “We staan altijd klaar om de eigendommen van Amerika te beschermen.”

“We bereiden ons voor op het ergste”

Het weerhield de eerste Amerikanen zich er niet van zich eerder deze week alvast te melden. Verslaggevers van de Las Vegas Revie Journal zagen al meerdere ‘kampen’ langs snelweg 375 bij het plaatsje Rachel. Bezoekers zetten er hun tenten of campers neer, en lieten vlaggen met ‘alien-thema’s’ wapperen. Ken Faulhaver (64) zei tegen de krant: “We zijn hier voor het spektakel. We kopen wat bier en wat merchandise.” En: “Ik hoop dat de aliens komen om mee te feesten.” Bewoners van de dorpjes in het gebied vreesden dat er een massa mensen zou opdagen, zo vertelden ze aan verschillende persbureaus. “We bereiden ons voor op het ergste”, aldus een bewoner.

Dat is onder meer omdat festivalorganisatoren en andere commerciële partijen op het idee van de bestorming zijn gedoken. Op meerdere plekken in de regio zijn dezer dagen (muziek)evenementen onder namen als Area 51 Base Camp en Alienstock. Naast muziek staan er lezingen (over aliens) en films (ook over aliens) gepland.

Bier en vlaggen

Biermerk Budweiser sponsort een van de feesten en verkoopt ‘buitenaardse’ hoofddeksels. Ook maakte het merk een vlag (voor 75 dollar) die de aandacht moet trekken van UFO’s en hun bemanning. Fastfoodgigant Arby’s verkoopt vanuit een special opgezet restaurant “het beste vlees voor buitenaards leven”.

“Dit fenomeen is een perfecte combinatie van onze interesse in aliens, het buitenaardse, overheidssamenzweringen en de wens om te weten wat we nog niet weten”, zegt socioloog Michael Ian Borer van de Universiteit van Nevada tegen persbureau AP.

{ https://www.hln.be/ )

22-09-2019 om 20:47 geschreven door peter  

Jamie Carter - Contributor

Are there relic alien spacecraft on asteroids close to Earth that may have been observing the planet for longer than humans have existed?

A thought-provoking, if unlikely-sounding new theory that near-Earth ‘companion’ asteroids may contain live or ancient robotic probes sent from faraway civilizations comes from Dr. James Benford at Microwave Sciences in Lafayette, California, whose paper "Looking for Lurkers: Co-Orbiters as SETI Observables," is published this week in the Astronomical Journal.

Before we dismiss it as crazy talk, consider that Benford thinks that by ruling-out the presence of alien probes and extraterrestrial archeology on rocks that are often close to Earth would bring us to a profound conclusion: there is no-one out there and we’re truly alone.

What are co-orbital objects?

In this context, a co-orbital is an asteroid that goes around the Sun on the same, or similar, orbital path to Earth. Co-orbital objects approach Earth very closely every year at distance is much shorter than anything except the moon.

Consequently, co-orbitals could be a great place to watch Earth from. Not only would any alien probes on co-orbital objects be concealed, but they would also be anchored and able to access solar energy. They could possibly sustain themselves for many thousands of years.

What are ‘lurkers?’

According to Benford, a lurker is a hidden, unknown and unnoticed observing probe, and they could have been sent to observe Earth long ago. “They may respond to an intentional signal and may not, depending on unknown alien motivations,” reads a news release covering Benford’s new paper. “Lurkers would likely be robotic, like our own Voyager and New Horizons probes.” The space probes currently the furthest from us, Voyagers 1 and 2 (launched in the late 1970s) and New Horizons (launched in 2006 and the fastest man-made object ever launched from Earth) have gotten much further than the outskirts of our own solar system.

There’s also obviously a limit to how long any alien space probes sent to study Earth could last. “Perhaps probes are waiting on these objects, listening to us and waiting for us to find them” reads the paper. “They may remain silent and simply report back to wherever they communicate to”. Benford suggests that if we did find such a “lurker” we could simply photograph it and send it in a message simply to say “we see you” and wake the probe from its passive state.

The idea is loosely inspired by the concept of using a Bracewell probe for allowing widely separated civilizations to communicate.

How crazy is this theory?

At first glance, it’s way out there, but Benford thinks that the process of looking for relic alien spacecraft in Earth’s cosmic backyard is critical in us understanding the possibility of extra-terrestrial intelligence in our galaxy. “If we find nothing there, this gives us a profound result: no one has come to look at the life of the Earth, which has been evident in our atmosphere in spectral lines over interstellar distances for over a billion years.” Spectral lines from light are used by astronomers to identify atoms, molecules and elements present in a planet.

Benford is arguing that if we find nothing on the co-orbital objects around Earth, then the chances of there being more advanced alien civilisations anywhere in our galaxy become more remote.

What is 2016 HO3?

Between 120 and 300 ft. in diameter and also known as ‘Earth's Constant Companion' by NASA, 2016 HO3 is the smallest, closest, and most stable known quasi-satellite of Earth. Discovered on April 27, 2016, by the Pan-STARRS 1 asteroid survey telescope on Haleakala, Hawaii, 2016 HO3 loops around the Earth every year during Earth’s orbit of the Sun. It’s been stable for at least 100 years and will remain so for many hundreds of years to come. However, 2016 HO3 is always at least nine million miles away, so never a threat to Earth.

Benford thinks we should study co-orbital objects both in the electromagnetic spectrum of microwaves and light, and also using planetary radar.

China’s plan to visit 2016 HO3

Getting to 2016 HO3 from Earth orbit requires relatively little rocket propulsion, so it’s no surprise that the China National Space Administration (CNSA) has announced plans to send a probe. A robotic mission that would return samples could launch in 2024.

The search for extraterrestrial life is currently focused on distant exoplanets. It’s a sobering thought that asteroids in our own celestial backyard may have hosted alien probes sent to study Earth many thousands of years ago by extraterrestrial civilizations. Wishing you clear skies and wide eyes.

{ https://www.forbes.com/ }

22-09-2019 om 18:29 geschreven door peter  

Inner Earth Civilizations? Unraveling The Mystery Behind Our Planet’s Massive Inner Ocean

One of my all-time favorite books is without a doubt Journey to the Center of the Earth, written by world-famous Author Jules Verne.

The story written by Verne involves a German professor called Otto Lidenbrock who was convinced that there are volcanic tubes that lead toward the center of our planet.

Lidenbrock, his nephew Axel, and their guide Hans descend into the Icelandic volcano Snæfellsjökull and encounter many adventures along the way, including prehistoric animals and dangers. Eventually, they resurface in southern Italy, at the Stromboli volcano.

In the book, Verne describes a MASSIVE ocean that exists inside our planet.

He explains how: a vast expanse of water, the beginning of a lake or an ocean, extended beyond the limits of sight.

Further, the view followed its mass outlined on the misty background of the horizon. It was a true ocean, capriciously contoured by the terrestrial shores, but deserted and with a terribly wild aspect.

The book was a science fiction bestseller, and despite many people believing that something like this may be possible, the idea remained firmly a science fictional idea.

Now, what if what was once thought to be a mere fantasy of the writer, was, in fact, closer to reality?

Is it even possible that there really is an underground ocean beneath or feet?

An article published in the journal Nature points in that direction.

As it turns out, scientists discovered a while ago, a diamond-rich in water with traces of a mineral called ringwoodite (in honor of its discoverer, the geochemist Alfred Ringwood).

The diamond originally came from an area that separates the upper terrestrial mantle from the lower one, that is, between four and six hundred kilometers beneath our feet.

So, what does that has to do with Verne, Inner Earth, and an ocean beneath our feet?

The fact is that the diamond found was associated with water molecules in a significant proportion (1.5%), which leads experts to propose the theory that this zone of transition of the mantle is very rich in water.

In fact, scientists have proposed that there is so much water beneath the surface of our planet, that we can cover the surface of our planet entirely in water. The existence of this ‘underground ocean’ would explain the great volcanic and tectonic dynamism of the planet.

Graham Pearson, a researcher from the University of Alberta (Canada) says that the ringwoodite found “provides confirmation that there really are pockets of water in the depths of the Earth.”

That, however, is a theoretical confirmation, of course, since due to lack of equipment and technology it would be impossible to obtain physical evidence from the mantle directly.

That kinda’ sucks since, despite the fact that humans have made it to space, landed on the moon and explored distant alien worlds, we’ve still not explored what exactly lies beneath our ocean, and what mysteries may be hidden beneath the surface of our planet.

Alfred Ringwood proposed that the mineral that bears his name could be found in the transition zone of the mantle, originated by the high pressures and temperatures that are found beneath deep beneath the surface.

But if we can’t go down there, how did scientists find the diamond?

Experts believe that the diamond surfaced in a volcanic eruption in a kimberlite wash (an igneous rock formed from magma and that is the deepest).

It was only three millimeters wide and lacked commercial value, but it was sold to scientists who were looking for other types of rocks, and who came up with something that was priceless: inside the diamond, there was a microscopic trail of ringwoodite.

But not everyone is convinced that a massive underground ocean exists and not all scientists believe that the result of the diamond analysis should be extrapolated to the theory of a massive underwater ocean based on such a small sample of ringwoodite.

Moreover, some scientists even admit that even if there is an ocean beneath our feet, it would not be in liquid form but under a molecular variant called hydroxyl, with only one atom of oxygen and another of hydrogen instead of the two.

David Wilcock and Earth’s Inner Civilizations

In 2015, an article appeared on Coast To Coast AM, where author and researcher David Wilcock discusses Earth’s Inner Civilizations.

Wilcock told C2C that an alliance of ancient civilizations currently resides inside the Earth, and they may soon reveal themselves to the ‘outer’ world.

During the formation of all watery planets in the universe, he explained, hollow cavities form below the surface of the crust and have their own biome that features bacteria which gives off natural light.

“What this means is that you can actually live inside caverns in the Earth that have visible light,” he marveled.

Based on his research, Wilcock said, “it appears that these cavities are used so that more advanced civilizations have a place they can live while they’re managing what takes place on the surface.”

Over the span of the planet’s history, he explained, various advanced societies, such as the Atlanteans, took refuge underground in order to survive tumultuous times and ultimately settled in their new subterranean location.

While the presence of these civilizations has been a part of UFO lore for decades, he contended that the government has direct knowledge of their presence due to accidentally discovering them via clandestine projects aimed at building secret underground bases.

“They’ll have these tunnel boring machines and sometimes they break through into someplace they’re not supposed to go,” Wilcock claimed, “and there’s already people there.”

• For the full interview with David Wilcock click here.
• Featured image by Leon Tukker. Image Posted with permission.

{ https://www.ancient-code.com/ }

22-09-2019 om 18:17 geschreven door peter  

Inner Earth Civilizations Exist: the Science and Evidence of Habitable Underground Civilizations

Stillness in the Storm Editor: Why did we post this?

The preceding information discusses a scientific discovery that might provide evidence for the existence of large caverns within the earth capable of human habitation. Several alleged insiders and whistleblowers claimed that there are indeed advanced civilizations below the surface of the earth. While concrete evidence of such locations have yet to emerge, the preceding article offers evidence for existence of the so-called inner earth. The fact that this question of inner earth remains difficult to confirm means it is an excellent tool for exercising the discerning mind, which is an essential skill for the development of a truly wise and sovereign individual.

– Justin

{ https://stillnessinthestorm.com/ }

22-09-2019 om 18:07 geschreven door peter  

For the sake of their study, Dr. Way and Dr. Del Genio created a series of five simulations that considered what the environment of Venus would be like based on different levels of water coverage. This consisted of adapting a 3D general circulation model that took into account changing atmospheric compositions and the gradual increase in solar radiation as the Sun became warmer over the course of its lifetime.

In three of the five scenarios, Way and Del Genio assumed that the topography of Venus was much as the same as it is today, the ocean ranged from a minimum depth of 10 m (~30 ft) to a maximum of about 310 m (~1000 ft) and a small amount of water was locked in the soil. They also considered a scenario with Earth’s topography and a 310-meter ocean, and another where Venus was entirely covered in an ocean 158 m (~500ft).

In the end, all five simulations indicated the same thing: that Venus would have been able to maintain stable temperatures – from a low of 20 °C (68 °F) to a high of 50 °C (122 °F) – for about three billion years. Were it not for a series of event that caused 80% of the planet’s surface to be resurfaced (which led to the outgassing of CO² contained within the crust), it might even be habitable today. As Way explained it:

“Our hypothesis is that Venus may have had a stable climate for billions of years. It is possible that the near-global resurfacing event is responsible for its transformation from an Earth-like climate to the hellish hot-house we see today.

It all started about 4.2 billion years ago, a few hundred million years after Venus formed and had just finished a period of rapid cooling. At this point, assuming Venus underwent a similar process as Earth, it’s atmosphere would have been dominated by carbon dioxide. This would have slowly been absorbed by silicate rocks to form carbonates that were then locked into the planet’s crust.

By about 715 million years ago, according to Way and Del Genio’s study, the atmosphere would have been similar to what Earth’s is like today – composed predominantly of nitrogen gas with trace amounts of CO² and methane. These conditions could have remained stable up until present times were it not for a massive outgassing event.

The cause of this remains a mystery; however, scientists believe it was due to a geological event that caused 80% of the planet to resurface. This could have involved large amounts of magma bubbling up and releasing massive amounts of CO² into the atmosphere. The magma would have then solidified before reaching the surface, thus creating a barrier that prevented the CO² from being reabsorbed. As Way explained:

“Something happened on Venus where a huge amount of gas was released into the atmosphere and couldn’t be re-absorbed by the rocks. On Earth we have some examples of large-scale outgassing, for instance the creation of the Siberian Traps 500 million years ago which is linked to a mass extinction, but nothing on this scale. It completely transformed Venus.”

This would explain how Venus’ atmosphere was thickened to the point where it was over 90 times as dense as Earth’s (92 bar compared to 1 bar). Combined with the high concentrations of CO², this would have led to a runaway Greenhouse Effect that would explain how the planet became the hellish place we know today, where surface temperatures average 462 °C (864 °F).

This flies in the face of conventional notions of habitability, which state that Venus’ orbit places it beyond the inner edge of our Sun’s habitable zone (HZ). Within this “Venus Zone”, according to conventional wisdom, a planet absorbs too much solar radiation to ever be able to maintain liquid water on its surface. But as Way indicated, their simulations all indicated otherwise:

 “Venus currently has almost twice the solar radiation that we have at Earth. However, in all the scenarios we have modelled, we have found that Venus could still support surface temperatures amenable for liquid water.”

These findings are in line with a similar study that Way and Del Genio conducted in 2016 with colleagues from the NASA Goddard Space Flight Center, the Planetary Science Institute (PSI), Uppsala University and Columbia University. For this study, their team created a suite of 3D climate simulations using data from the Magellan mission that examined how the presence of an ocean on ancient Venus would affect its habitability.

From this, they determined that if Venus had a rotational period slower than about 16 Earth days, its climate would have remained habitable until 715 million years ago. However, there are still two major unknowns that need to be addressed before scientists can say with confidence that Venus was habitable until very recently.

First, scientists will need to determine how quickly Venus cooled and if it was able to condense liquid water on its surface in the first place. Second, it remains unknown whether the global resurfacing event that led to Venus’ transition was a single event or merely part of a series that had been taking place for billions of years.

“We need more missions to study Venus and get a more detailed understanding of its history and evolution,” said Way. “However, our models show that there is a real possibility that Venus could have been habitable and radically different from the Venus we see today. This opens up all kinds of implications for exoplanets found in what is called the ‘Venus Zone’, which may in fact host liquid water and temperate climates.”

Think of it… had Venus not undergone a massive resurfacing event (or a series of them), humanity would have only needed to look next-door for proof of extra-terrestrial life. For that matter, had Mars not lost its magnetosphere 4.2 billion years ago, it could have produced life of its own that would still be around today. Our one Solar System could have had not one, but three life-bearing planets (neighboring at that)!

These findings are likely to be encouraging for those who believe that Venus should be terraformed someday. Knowing that the planet once had a stable climate, and could maintain it despite its orbit, effectively means that any ecological engineering we do there would stick.

That means that Venus could someday be made into a balmy world that’s mostly covered with oceans with few large continents and extensive archipelagos. Sound like any pl }ace you know?

• Further Reading: Europlanet Society, EPSC

{ https://www.universetoday.com/ }

22-09-2019 om 17:59 geschreven door peter