This dead star offers a glimpse of our solar system’s eventual fate

This dead star offers a glimpse of our solar system’s eventual fate

By Ashley Strickland, CNN

https://www.cnn.com/2021/10/16/world/science-newsletter-wt-scn-solar-system/index.html

Updated 10:57 AM ET, Sat October 16, 2021

See Shatner's emotional remarks after landing

See Shatner’s emotional remarks after landing 02:26A version of this story appeared in CNN’s Wonder Theory newsletter. To get it in your inbox, sign up for free here. Tell us what you’d like to see more of in the newsletter at sciencenewsletter@cnn.com.

(CNN)Space truly is the final frontier.Fifty-five years after the world met Capt. James T. Kirk and his crew on the USS Enterprise, William Shatner was able to boldly go there.

The “Star Trek” actor became the oldest person to ever travel to space. The trip was a blisteringly brief 10 minutes aboard Blue Origin’s New Shepard spacecraft, but Shatner was incredibly moved by the “profound experience” of seeing the “life and nurturing” of Earth.

Current-day scientists are living up to the words spoken by Shatner in the show’s introduction half a century ago: exploring strange new worlds and seeking out new life.

And today, NASA’s Lucy mission lifted off on a quest to understand how our solar system formed 4.5 billion years ago.

Once upon a planet

This illustration shows a Jupiter-like planet orbiting a dead white dwarf star.This illustration shows a Jupiter-like planet orbiting a dead white dwarf star.Our corner of the universe may be in for a rude awakening, but we’ve got 5 billion years to prepare.Researchers observed a giant planet orbiting a white dwarf, or the remains of a dead star, at the heart of our galaxy. It showed what may happen in our solar system when the sun dies.While Saturn and Jupiter will likely survive the violent evolution, it’s a different story for the other planets.

Consequences

With sea levels steadily on the rise, 50 major coastal cities need to adapt in unprecedented ways to stay afloat, according to new research.The results show striking visual contrasts between the world as we know it today and our underwater future, if the planet warms to 5.4 degrees Fahrenheit (3 degrees Celsius) above preindustrial levels.Use our visual sliders to compare how California’s Santa Monica pier and London’s Buckingham Palace would appear if global warming and sea level rise can’t be stopped. The sight of such iconic places submerged is startling.

Wild kingdom

Italian photographer Stefano Unterthiner captured this image of two reindeer battling for control.Italian photographer Stefano Unterthiner captured this image of two reindeer battling for control.Stunning photos revealing our wonderfully wild world have won in 19 categories of the 2021 Wildlife Photographer of the Year competition.Photographers from 95 countries submitted a record-breaking 50,000 entries, with shots including a gorilla enjoying a rain shower and a tent spider’s web as an auto-rickshaw passed by in India (which was captured by a 10-year-old).And enjoy a peek at the cuter side of wild animals with this litter of adorable newborn cheetahs.Five cubs were born to cheetah mom Rosie Tuesday morning at Virginia’s Smithsonian Conservation Biology Institute. You can watch the feline family via the Cheetah Cub Cam, which features live footage of the den. If you listen closely, you can hear the cubs chirping.

Across the universe

An outburst of cosmic explosions has been traced back to a mysterious repeating fast radio burst in space called FRB 121102. Researchers detected 1,652 bursts over the course of 47 days.Fast radio bursts, or FRBs, are millisecond-long emissions of radio waves in space. This one has been traced to a small dwarf galaxy over 3 billion light-years away.Scientists have yet to determine the actual cause of the flashes, and, naturally, everyone has a theory (greetings, aliens!). But researchers suspect these celestial phenomena as the more likely cause.

We are family

This aerial photo shows the Tel Yavne excavation site, where a massive wine production facility was discovered.This aerial photo shows the Tel Yavne excavation site, where a massive wine production facility was discovered.As humans, it appears we have a long history of indulgences.Archaeologists uncovered a 1,500-year-old wine factory in the Israeli town of Yavne after toiling away at the site for two years. A famous brand of wine from the ancient world was likely made at the world’s largest wine factory from the Byzantine period, they said.Meanwhile, researchers studying fossilized poop discovered that Iron Age Europeans enjoyed blue cheese and beer in their diet.And charred seeds found in a hearth once belonging to hunter-gatherers in Utah suggest humans used tobacco over 12,000 years ago — 9,000 years earlier than previously thought.

Curiosities

You never know what you’ll find:– This “living fossil” creature was found in an incredibly unlikely place for the first time in documented history.– An Australian-made rover will land on the moon in 2026 and collect lunar soil that may contain oxygen, which NASA hopes to extract.

— These carved stone statues were used as garden ornaments — until it was revealed that they were Egyptian relics dating back thousands of years.Like what you’ve read? Oh, but there’s more. Sign up here to receive in your inbox the next edition of Wonder Theory, brought to you by CNN Space and Science writer Ashley Strickland, who finds wonder in planets beyond our solar system and discoveries from the ancient world.

Dropping Oxygen Will Eventually Suffocate Most Life on Earth

https://www.sciencealert.com/enjoy-it-while-you-can-dropping-oxygen-will-eventually-suffocate-most-life-on-earth

(Aaron Foster/The Image Bank/Getty Images)ENVIRONMENT

Enjoy It While You Can:

DAVID NIELD9 OCTOBER 2021

For now, life is flourishing on our oxygen-rich planet, but Earth wasn’t always that way – and scientists have predicted that, in the future, the atmosphere will revert back to one that’s rich in methane and low in oxygen.https://39e044c1400623755f8709ae964ab15e.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

This probably won’t happen for another billion years or so. But when the change comes, it’s going to happen fairly rapidly, the study from earlier this year suggests.

This shift will take the planet back to something like the state it was in before what’s known as the Great Oxidation Event (GOE) around 2.4 billion years ago.

What’s more, the researchers behind the new study say that atmospheric oxygen is unlikely to be a permanent feature of habitable worlds in general, which has implications for our efforts to detect signs of life further out in the Universe.

“The model projects that a deoxygenation of the atmosphere, with atmospheric O2 dropping sharply to levels reminiscent of the Archaean Earth, will most probably be triggered before the inception of moist greenhouse conditions in Earth’s climate system and before the extensive loss of surface water from the atmosphere,” wrote the researchers in their published paper.

At that point it’ll be the end of the road for human beings and most other life forms that rely on oxygen to get through the day, so let’s hope we figure out how to get off the planet at some point within the next billion years.

To reach their conclusions, the researchers ran detailed models of Earth’s biosphere, factoring in changes in the brightness of the Sun and the corresponding drop in carbon dioxide levels, as the gas gets broken down by increasing levels of heat. Less carbon dioxide means fewer photosynthesizing organisms such as plants, which would result in less oxygen.

Scientists have previously predicted that increased radiation from the Sun would wipe ocean waters off the face of our planet within about 2 billion years, but the new model – based on an average of just under 400,000 simulations – says the reduction in oxygen is going to kill off life first.

“The drop in oxygen is very, very extreme,” Earth scientist Chris Reinhard, from the Georgia Institute of Technology, told New Scientist earlier this year. “We’re talking around a million times less oxygen than there is today.”

What makes the study particularly relevant to the present day is our search for habitable planets outside of the Solar System.

Increasingly powerful telescopes are coming online, and scientists want to be able to know what they should be looking for in the reams of data these instruments are collecting.

It’s possible that we need to be hunting for other biosignatures besides oxygen to have the best chance of spotting life, the researchers say. Their study is part of the NASA NExSS (Nexus for Exoplanet System Science) project, which is investigating the habitability of planets other than our own.

According to the calculations run by Reinhard and environmental scientist Kazumi Ozaki, from Toho University in Japan, the oxygen-rich habitable history of Earth could end up lasting for just 20-30 percent of the planet’s lifespan as a whole – and microbial life will carry on existing long after we are gone.

“The atmosphere after the great deoxygenation is characterized by an elevated methane, low-levels of CO2, and no ozone layer,” said Ozaki. “The Earth system will probably be a world of anaerobic life forms.”

The research has been published in Nature Geoscience.

A version of this article was first published in March 2021.

Razor Thin: A New Perspective on Earth’s Atmosphere

Published 2 days ago 

on September 3, 2021

ByCarmen Ang

Graphics/Design:

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Earth's Atmosphere

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Razor Thin: A New Perspective on Earth’s Atmosphere

Earth is the only known planet that sustains life. Its atmosphere provides us with oxygen, protects us from the Sun’s radiation, and creates the barometric pressure needed so water stays liquid on our planet.

But while Earth’s atmosphere stretches for about 10,000 km (6,200 miles) above the planet’s surface, only a thin layer is actually habitable.

This graphic, inspired by Andrew Winter, shows just how small Earth’s “habitable zone” is, using the state of Florida as a point of reference.

Earth’s Like an Onion: It Has Layers

Our planet’s atmosphere is made up of a unique cocktail of gases—roughly 78% nitrogen and 21% oxygen, with trace amounts of water, argon, carbon dioxide, and other gases.

It’s separated into five different layers:

  • Exosphere: The uppermost layer of our atmosphere that melds into outer space.
  • Thermosphere: Begins at around 80 km (50 miles) above sea level and extends to approximately 600 km (372 miles), reaching temperatures as high as 2,000°C (3,600°F).
  • Mesosphere: Around 30 km (19 miles) in range, meteors burn as they pass through this layer, creating “shooting stars.”
  • Stratosphere: Home to the ozone layer, which is responsible for absorbing a majority of the sun’s radiation.
  • Troposphere: The closest layer to ground. It stretches about 7–15 kilometers (5–10 miles) from the surface.

The troposphere makes up approximately 75-80% of the atmosphere’s mass, as it’s where most of the dust, ash, and water vapor are stored. But only a part of this layer is suitable for human life—in fact, the atmosphere’s habitable zone is so small, several mountain ranges extend beyond it.

Reaching Into Earth’s Atmosphere: Extremely High Altitudes

Elevations above 5,500 meters (18,000 ft) are considered extremely high altitude and require special equipment and/or acclimatization in order to survive. Even then, those who choose to venture to extreme heights run the risk of getting altitude sickness.

When it comes to the world’s tallest mountain ranges, the Himalayas are the highest. At their peak, Mount Everest, the Himalayas reach 8,848 m (29,000 ft) above sea level.

Mountain rangeHighest mountainHeightCountries
HimalayasMount Everest8,848 mNepal, China
KarakoramK28,611 mPakistan
Hindu KushTirich Mir7,708 mPakistan
Kongur ShanKongur Tagh7,649 mChina
Daxue MountainsMount Gongga7,556 mChina
Pamir MountainsIsmoil Somoni Peak7,495 mTajikistan
Kakshaal TooJengish Chokusu7,439 mChina, Kyrgyzstan
Nyenchen Tanglha MountainsGyala Peri7,294 mChina
AndesAconcagua6,960 mArgentina
Kunlun MountainsChakragil6,760 mChina

Showing 1 to 10 of 26 entriesPreviousNext

Despite the dangers of extreme altitude, hundreds of mountaineers attempt to climb Mount Everest each year. On Everest, the region above 8,000 m (26,000 feet) is referred to as the “death zone,” and climbers have to bring bottled oxygen on their trek in order to survive.

Life Beyond Earth

Earth is the only known planet with an atmosphere we can survive in. And even on Earth, certain areas are considered dead zones.

But there may be other life forms out in the galaxy that we haven’t discovered. Recent research in The Astrophysical Journal predicts there are at least 36 intelligent civilizations throughout the galaxy today.

So life may very well exist beyond Earth. It just might look a bit different than we’re used to.

Scientists identify 29 planets where aliens could observe Earth

Astronomers estimate 29 habitable planets are positioned to see Earth transit and intercept human broadcasts

space
The scientists identified 1,715 star systems where alien observers could have discovered Earth in the past 5,000 years by watching it ‘transit’ across the face of the sun. Photograph: c/o Cornell

Ian Sample Science editor@iansampleWed 23 Jun 2021 11.00 EDT

For centuries, Earthlings have gazed at the heavens and wondered about life among the stars. But as humans hunted for little green men, the extraterrestrials might have been watching us back.

In new research, astronomers have drawn up a shortlist of nearby star systems where any inquisitive inhabitants on orbiting planets would be well placed to spot life on Earth.

The scientists identified 1,715 star systems in our cosmic neighbourhood where alien observers could have discovered Earth in the past 5,000 years by watching it “transit” across the face of the sun.

Among those in the right position to observe an Earth transit, 46 star systems are close enough for their planets to intercept a clear signal of human existence – the radio and TV broadcasts which started about 100 years ago.Advertisement

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The researchers estimate that 29 potentially habitable planets are well positioned to witness an Earth transit, and eavesdrop on human radio and television transmissions, allowing any observers to infer perhaps a modicum of intelligence. Whether the broadcasts would compel an advanced civilisation to make contact is a moot point.

“One way we find planets is if they block out part of the light from their host star,” said Lisa Kaltenegger, professor of astronomy and director of the Carl Sagan Institute at Cornell University in New York. “We asked, ‘Who would we be the aliens for if somebody else was looking?’ There is this tiny sliver in the sky where other star systems have a cosmic front seat to find Earth as a transiting planet.”

Earthly astronomers have detected thousands of planets beyond the solar system. About 70% are spotted when alien worlds pass in front of their host stars and block some of the light that reaches scientists’ telescopes. Future observatories, such as Nasa’s James Webb Space Telescope due to launch this year, will look for signs of life on “exoplanets” by analysing the composition of their atmospheres.

To work out which nearby star systems are well placed to observe an Earth transit, Kaltenegger and Dr Jackie Faherty, an astrophysicist at the American Museum of Natural History, turned to the European Space Agency’s Gaia catalogue of star positions and motions. From this they identified 2,034 star systems within 100 parsecs (326 light years) that could spot an Earth transit any time from 5,000 years ago to 5,000 years in the future.

One star known as Ross 128, a red dwarf in the Virgo constellation, is about 11 light years away – close enough to receive Earth broadcasts – and has a planet nearly twice the size of Earth. Any suitably equipped life on the planet could have spotted an Earth transit for more than 2,000 years, but lost the vantage point 900 years ago. If there is intelligent life on any of the two known planets orbiting Teegarden’s star, 12.5 light years away, it will be in a prime position to watch Earth transits in 29 years’ time.https://04d10349443cb018b282b3a98518c963.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

At 45 light years away, another star called Trappist-1 is also close enough to eavesdrop on human broadcasts. The star hosts at least seven planets, four of them in the temperate, habitable zone, but they will not be in position to witness an Earth transit for another 1,642 years, the scientists write in Nature.

The findings come as the US government prepares to publish a hotly anticipated report on unidentified flying objects (UFOs). The report from the Pentagon’s Unidentified Aerial Phenomena Task Force, which was set up to gain insights into the nature and origins of unknown aircraft, is not expected to reveal evidence of alien antics, or rule it out.

Prof Beth Biller at Edinburgh University’s Institute for Astronomy, who was not involved in the Nature study, said the work could change how scientists approach Seti, the search for extraterrestrial life. “What was striking to me was how few of the stars within 100 parsecs could have viewed a transiting Earth,” she said.

“The transit method requires a very precise alignment between the transiting planet, its star, and the sun for a given planet to be detectable, so this result is not surprising. Now I am curious about what fraction of the stars in the Gaia catalogue of nearby stars have the right vantage point to detect the Earth via other exoplanet detection methods, such as the radial velocity method or direct imaging!”

A Record-Breaking Flare Has Erupted From The Closest Star to Our Solar System

https://www.sciencealert.com/our-nearest-stellar-neighbor-has-erupted-with-a-massive-flare-and-it-s-a-record-breaker

(NRAO/S. Dagnello)SPACE

MIKE MCRAE23 APRIL 2021

Two years ago, our star’s next door neighbor – Proxima Centauri – got a little emotional. It happens from time to time, only this time, the small red star really let go. A storm of fury that breaks its previous records, outdoing anything our own Sun could manage by magnitudes.https://57dde41067b8deca0791b4bd07473c84.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

Sure, we were eavesdropping, but it’s all in the name of science. Besides, we now have some galactic gossip we’re dying to share – this was not your typical solar eruption.

As far as neighbors go, you could do worse than Proxima Centauri. At a mere 4 light-years (just over 30 trillion kilometers) over the back fence, it’s close enough to keep an eye on without being prone to blowing up in a life-destroying cataclysm.  

That doesn’t mean it’s quiet. Like most hot-tempered red dwarf stars, Proxima Centauri vents its rage every now and then in a brilliant display of radiation, spilling streams of plasma and light out into its system with a manic snapping and rejoining of its magnetic fields.

This is bad news for its host of innermost planets, which periodically cop a roasting that makes it unlikely that any complex organic chemistry on the surface would have remained intact long enough to spark into life.

But for us, watching these outbursts from a safe distance gives insight into the mechanisms of stellar physics. In 2019, astronomers trained nine telescopes around the globe on Proxima Centauri for a marathon 40-hour session.https://57dde41067b8deca0791b4bd07473c84.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

They weren’t planning on missing any details – using telescopes such as the Australian Square Kilometre Array Pathfinder, the Atacama Large Millimeter/submillimeter Array, and the Transiting Exoplanet Survey Satellite, they listened in on multiple frequencies, from radio to X-ray.

“It’s the first time we’ve ever had this kind of multi-wavelength coverage of a stellar flare,” says astrophysicist Meredith MacGregor from University of Colorado Boulder.

“Usually, you’re lucky if you can get two instruments.”

And oh boy, they weren’t disappointed. Not only did five of their instruments catch sight of the largest flare to be observed in the Proxima Centauri system to date, the signature of the eruption was strange enough to suggest they had an entirely new kind of solar event on their hands.

Back in 2016, astronomers caught a similar superflare, one that could be seen without telescopes.

Though technically bigger, becoming 14,000 times brighter over the span of a few seconds, this more recent activity was largely in the form of wavelengths we can’t see, such as in the ultraviolet and radio parts of the spectrum.

Finding such a strong surge in the radio zone of millimeter range waves was completely unexpected, making this flare really worth paying attention to.

“In the past, we didn’t know that stars could flare in the millimeter range, so this is the first time we have gone looking for millimeter flares,” says MacGregor.  

The timing and energies of the different wavelengths of light in the flare provide astrophysicists with a novel look into the mechanisms behind flare production, adding details to our models.

Knowing that solar flares emit in this part of the spectrum means researchers will be more inclined to train a greater range of instruments on variable stars in the future in the hopes of catching a stray whisper of radiation they missed before.

“There will probably be even more weird types of flares that demonstrate different types of physics that we haven’t thought about before,” says MacGregor.

This won’t be the last tantrum we’ll see Proxima Centauri have, and probably not even the biggest. While this unusual eruption was the largest of the flares seen during the 40-hour window of observations, it wasn’t the only one the researchers saw.

In fact, our tiny neighbor could be in a near constant rage, unleashing its hostility at least once a day. Maybe more.

At least its temper isn’t as bad as AD Leonis, another angry red dwarf in our neighborhood. Now there’s some gossip.

This research was published in The Astrophysical Journal Letters.

This ‘super-Earth’ seems lovely, until you look up

https://www.yahoo.com/entertainment/super-earth-seems-lovely-until-213646934.html

Mike WehnerMon, April 19, 2021, 2:36 PM·3 min read

Earth is great, but what if it were bigger? So-called “super-Earths” are rocky worlds like our own but are several times bigger, and could offer us a new home if we ever were to leave our solar system. Some of the super-Earths that scientists have discovered are too far away from their star to be warm enough for liquid water, so those are a no-go. Some are within or near the habitable zone, which is great news for us, but the vast majority of those are too distant to consider visiting right now. A newly-discovered super-Earth around the star GJ-740 is special because it’s very close to Earth, relatively speaking — only 36 light-years — but there’s another problem. It’s very, very hot.

The planet is estimated to be around three times as massive as Earth. That’s a sizeable chunk of rock, and it’s orbiting a star that is much cooler than our own Sun. GJ-740 is a red dwarf, meaning that its peak temperature is thousands of degrees cooler than our own Sun. Unfortunately, the planet is incredibly close to its star, canceling most of the benefits of orbiting a cooler star and ensuring that the super-Earth’s surface is still very, very warm.

Earth takes a full 365 days to complete an orbit of our Sun. On this newly-discovered super-Earth, a day is much shorter. In fact, the planet completes a full “year” in a mere 2.4 Earth days. That indicates that the planet is incredibly close to its star and, as a result, is absorbing a huge amount of the star’s radiation in the form of heat and various wavelengths of light. The scientists don’t offer a guess as to how hot the planet’s surface is, but it would be absolutely unlivable for any life forms originating on Earth.- ADVERTISEMENT -https://s.yimg.com/rq/darla/4-6-0/html/r-sf-flx.html

“This is the planet with the second shortest orbital period around this type of star. The mass and the period suggest a rocky planet, with a radius of around 1.4 Earth radii, which could be confirmed in future observations with the TESS satellite”, Borja Toledo Padrón, the first author of the article, said in a statement. “The search for new exoplanets around cool stars is driven by the smaller difference between the planet’s mass and the star’s mass compared with stars in warmer spectral classes (which facilitates the detection of the planets’ signals), as well as the large number of this type of stars in our Galaxy”

Story continues https://www.yahoo.com/entertainment/super-earth-seems-lovely-until-213646934.html

Earth’s oxygen will be gone in 1 billion years

Posted by Kelly Kizer Whitt in EARTH | March 7, 2021

A billion years from now, as the sun heats up, the warmer atmosphere will break down carbon dioxide, killing off plant life, which in turn will shut off Earth’s source of oxygen.Sharing is caring!

Partial view of Earth from orbit with clouds and fuzzy atmosphere visible aganist black space.

The oxygen currently in Earth’s atmosphere will be gone in a billion years, say scientists. This image of Earth’s atmosphere was taken from the International Space Station on February 26, 2021. Image via NASA.https://8505ac7d1ccf4966634f1f008ed6ceef.safeframe.googlesyndication.com/safeframe/1-0-37/html/container.html

Take a deep breath. The air expanding your chest is mostly nitrogen and oxygen, the chief components of our atmosphere. Oxygen exists in our atmosphere thanks to the exhalation of plants, through the process of photosynthesis. A study released in March 2021 shows that – a billion years from now, as the sun heats up – plants will die off, taking with them the oxygen in our atmosphere that humans and animals need to breathe.

Kazumi Ozaki of the University of Tokyo and Chris Reinhard of Georgia Tech modeled Earth’s climatic, biological and geological systems to fine-tune scientists’ understanding of future atmospheric conditions on Earth. They undertook the research as part of a NASA program called NExSS to explore and assess the habitability of exoplanets. Their study was published March 1, 2021, in the peer-reviewed journal Nature Geoscience.

Earth’s present atmosphere is made up of 78% nitrogen, 21% oxygen, 0.9% argon, and 0.1% other gases, including carbon dioxide, methane, water vapor and neon. Earth hasn’t always had such a high percentage of oxygen in its atmosphere. For Earth’s first 2 billion years, no oxygen existed in the atmosphere. Low levels of oxygen first appeared when cyanobacteria, also called blue-green algae, began releasing oxygen as a byproduct of photosynthesis. Then, about 2.4 billion years ago, Earth underwent the Great Oxidation Event. At this point, whether through a slackening in the outgassing of volcanoes or an evolutionary innovation that made cyanobacteria more successful, oxygen began to accumulate in larger amounts in the atmosphere, killing off some bacteria but allowing more complex life (us!) to evolve.

This oxygen utopia in which we currently live – where plants produce oxygen for humans and animals to breathe – is only a temporary condition on Earth. As Ozaki said:

We find that the Earth’s oxygenated atmosphere will not be a permanent feature.

Man with black hair and thin mustache wearing blue zip-up jacket.

Kazumi Ozaki of the University of Tokyo, lead author on the paper investigating the future of oxygen on Earth. Image via NASA.https://8505ac7d1ccf4966634f1f008ed6ceef.safeframe.googlesyndication.com/safeframe/1-0-37/html/container.html

As the solar system continues its life cycle, the aging sun will begin to heat up. The increased solar output will further warm the atmosphere, and the carbon dioxide will react to the increase in temperature by breaking down. Carbon dioxide levels will lower until photosynthesizing organisms – which rely on taking in carbon dioxide to live, just as we rely on oxygen to live – can no longer survive, removing the source of oxygen from Earth. (Read about how scientists believe that phytoplankton contribute between 50 to 85% of the oxygen in Earth’s atmosphere.) So when plants die from the lack of carbon dioxide, it’s not just a loss in the food chain but, crucially, a loss in the air they produce and the air we breathe.Skip Ad

While the end of oxygen is still a billion years away, when the depletion begins to take hold, it will occur rather rapidly, in about 10,000 years. Reinhard explained the severity of the change:

The drop in oxygen is very, very extreme; we’re talking around a million times less oxygen than there is today.

Man facing camera standing under a tree.

Chris Reinhard of Georgia Tech, one of the lead authors who researched the future amount of oxygen in Earth’s atmosphere. Image via NExSS.

The future deoxygenation event will coincide with a rise in methane, until methane levels are about 10,000 times more than exist in the atmosphere today. These shifts will occur too fast for adaptation in the biosphere. The ozone layer, made of oxygen, will vanish, and ultraviolet light and heat will aid in extinguishing both terrestrial and aquatic life. All but microbes will face extermination. Reinhard said:

A world where many of the anaerobic and primitive bacteria are currently hiding in the shadows will, again, take over.

Just as in the beginning, when life on Earth was in a microbial form before flourishing into the variety we see today, so too will the future look much like the past, as if the clock is running backward, and complex life forms will go extinct except for tiny colonies of cells.Dry ground and dead trees with wind-blown sand.

All plant and animal life on Earth needs oxygen to survive. A billion years from now, Earth’s oxygen will become depleted in a span of about 10,000 years, bringing about worldwide extinction for all except microbes. Image via Dikaseva/ Unsplash.

Studying the past and future of Earth is a gateway to understanding the conditions favorable to life on other planets. The presence of oxygen is an important factor in determining if life might exist on a planet. As we see with Earth, however, a planet that doesn’t have an oxygen signature may be capable of supporting life in the future or in the past.

Thus, while finding a planet with oxygen would be an exciting step toward finding life, not finding oxygen shouldn’t rule out the possibility that a planet ever had life.

Bottom line: A billion years from now, scientists say, as the sun heats up the warmer atmosphere will break down carbon dioxide, killing off plant life, which in turn will shut off Earth’s source of oxygen.

Source: The future lifespan of Earth’s oxygenated atmosphere

Volcanoes Might Light Up the Night Sky of This Super-Earth Exoplanet

TOPICS:AstronomyAstrophysicsExoplanetGeophysicsUniversity Of Bern

By UNIVERSITY OF BERN MARCH 6, 2021

This artist’s illustration represents the possible interior dynamics of the super-Earth exoplanet LHS 3844b. The planet’s interior properties and the strong stellar irradiation might lead to a hemispheric tectonic regime. Credit: © Universität Bern / University of Bern, Illustration: Thibaut Roger

Until now, researchers have found no evidence of global tectonic activity on planets outside our solar system. Under the leadership of the University of Bern and the National Center of Competence in Research NCCR PlanetS, scientists have now found that the material inside planet LHS 3844b flows from one hemisphere to the other and could be responsible for numerous volcanic eruptions on one side of the planet.

On Earth, plate tectonics is not only responsible for the rise of mountains and earthquakes. It is also an essential part of the cycle that brings material from the planet’s interior to the surface and the atmosphere, and then transports it back beneath the Earth’s crust. Tectonics thus has a vital influence on the conditions that ultimately make Earth habitable.

Until now, researchers have found no evidence of global tectonic activity on planets outside our solar system. A team of researchers led by Tobias Meier from the Center for Space and Habitability (CSH) at the University of Bern and with the participation of ETH Zurich, the University of Oxford and the National Center of Competence in Research NCCR PlanetS has now found evidence of the flow patterns inside a planet, located 45 light-years from Earth: LHS 3844b. Their results were published in The Astrophysical Journal Letters.

An extreme contrast and no atmosphere

“Observing signs of tectonic activity is very difficult, because they are usually hidden beneath an atmosphere,” Meier explains. However, recent results suggested that LHS 3844b probably does not have an atmosphere. Slightly larger than Earth and likely similarly rocky, it orbits around its star so closely that one side of the planet is in constant daylight and the other in permanent night – just like the same side of the Moon always faces the Earth. With no atmosphere shielding it from the intense radiation, the surface gets blisteringly hot: it can reach up to 800°C on the dayside. The night side, on the other hand, is freezing. Temperatures there might fall below minus 250°C. “We thought that this severe temperature contrast might affect material flow in the planet’s interior,” Meier recalls.

Tobias G. Meier, Center for Space and Habitability (CSH) and NCCR PlanetS, University of Bern. Credit: © Universität Bern / University of Bern, Photo: Felix Meier

To test their theory, the team ran computer simulations with different strengths of material and internal heating sources, such as heat from the planet’s core and the decay of radioactive elements. The simulations included the large temperature contrast on the surface imposed by the host star.

Flow inside the planet from one hemisphere to the other

Dr. Dan J. Bower, Center for Space and Habitability (CSH) and NCCR PlanetS, University of Bern. Credit: © Universität Bern / University of Bern, Photo: D. Bower

“Most simulations showed that there was only upwards flow on one side of the planet and downwards flow on the other. Material therefore flowed from one hemisphere to the other,” Meier reports. Surprisingly, the direction was not always the same. “Based on what we are used to from Earth, you would expect the material on the hot dayside to be lighter and therefore flow upwards and vice versa,” co-author Dan Bower at the University of Bern and the NCCR PlanetS explains. Yet, some of the teams’ simulations also showed the opposite flow direction. “This initially counter-intuitive result is due to the change in viscosity with temperature: cold material is stiffer and therefore doesn’t want to bend, break or subduct into the interior. Warm material, however, is less viscous – so even solid rock becomes more mobile when heated – and can readily flow towards the planet’s interior,” Bower elaborates. Either way, these results show how a planetary surface and interior can exchange material under conditions very different from those on Earth.

A volcanic hemisphere

Such material flow could have bizarre consequences. “On whichever side of the planet the material flows upwards, one would expect a large amount of volcanism on that particular side,” Bower points out.  He continues “similar deep upwelling flows on Earth drive volcanic activity at Hawaii and Iceland.”  One could therefore imagine a hemisphere with countless volcanoes – a volcanic hemisphere so to speak – and one with almost none.

“Our simulations show how such patterns could manifest, but it would require more detailed observations to verify. For example, with a higher-resolution map of surface temperature that could point to enhanced outgassing from volcanism, or detection of volcanic gases.  This is something we hope future research will help us to understand,” Meier concludes.

Asteroid the size of the Golden Gate Bridge will whiz past Earth in March

By Patrick Pester – Staff Writer 6 hours ago

Don’t panic; it won’t get that close.

3D illustration of an asteroid flying past Earth.3D illustration of an asteroid flying past Earth.(Image: © Aleksandra Sova via Shutterstock)

An asteroid as wide as the Golden Gate Bridge is long will hurtle past Earth next month. But although it will be the biggest and speediest asteroid to fly by our planet this year, there’s no reason to panic.

The space rock, officially called 231937 (2001 FO32), is about 0.5 to 1 mile (0.8 to 1.7 kilometers) in diameter and will come within 1.25 million miles (2 million kilometers) of Earth at 11:03 a.m. EST (1603 GMT) on March 21 — close enough and large enough to be classified as “potentially hazardous,” according to a database published by NASA’s Jet Propulsion Laboratory. 

An asteroid is designated as “potentially hazardous” when its orbit intersects with Earth’s at a distance of no more than about 4.65 million miles (7.5 million km) and it is bigger than about 500 feet (140 meters) in diameter, according to NASA’s Center for Near-Earth Object Studies (CNEOS)

Related: The 7 strangest asteroids: Weird space rocks in our solar system CLOSEhttps://imasdk.googleapis.com/js/core/bridge3.439.0_en.html#goog_1470463653Volume 0% PLAY SOUND

Small asteroids pass between Earth and the moon several times a month, and their fragments enter and break up in Earth’s atmosphere almost daily, according to NASA’s Planetary Defense Coordination Office (PDCO).

Telescopes in New Mexico that are part of the Lincoln Near-Earth Asteroid Research (LINEAR) program — an MIT Lincoln Laboratory program funded by the U.S. Air Force and NASA — detected the asteroid on March 23, 2001, according to EarthSky. Observatories have monitored it ever since. Scientists used these observations to calculate the asteroid’s orbit and determine how close the space rock will come to Earth when it whizzes by at almost 77,000 mph (124,000 km/h). 

No known asteroid poses a significant risk to Earth for the next 100 years. The current biggest known threat is an asteroid called (410777) 2009 FD, which has a 1 in 714 (less than 0.2%) chance of hitting Earth in 2185, according to NASA’s PDCO

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NASA is studying methods of deflecting asteroids that do end up on a collision course with Earth, such as by using the gravity of a flying spacecraft to slowly pull asteroids off their trajectory to a safe distance, according to NASA’s PDCO.

If you have a telescope with an aperture of at least 8 inches (20 centimeters), you might be able to spot the fast-moving space rock, according to EarthSky. To catch a glimpse in the southern U.S., point your telescope south-southeast between the constellations of Sagittarius and Corona Australis at 4:45 a.m. EST on March 20.

Originally published on Live Science.