* . *
  • About
  • Advertise
  • Privacy & Policy
  • Contact
Tuesday, September 2, 2025
Earth-News
  • Home
  • Business
  • Entertainment
    Country music star apologizes after drunken show ends with cops taking him down: ‘I’m not OK’ – PennLive.com

    Country Music Star Apologizes After Drunken Show Ends in Police Intervention: ‘I’m Not OK

    Comanche Nation Entertainment closes casino near Devol – KSWO 7News

    Comanche Nation Entertainment Closes Casino Near Devol in Surprising Move

    Erykah Badu Announces ‘Abi & Alan’ Album With The Alchemist Will Be Delayed – yahoo.com

    Erykah Badu Opens Up About the Delay of Her Highly Anticipated ‘Abi & Alan’ Album with The Alchemist

    If You Needed Some BTS Pics Of The Rock’s Tree Trunk Legs To Spice Up Your Day, We Got ‘Em – yahoo.com

    Need a Boost? Check Out These Epic BTS Shots of The Rock’s Tree Trunk Legs!

    Sabrina Carpenter’s pearl-clutching magic? Humor – CNN

    Sabrina Carpenter’s pearl-clutching magic? Humor – CNN

    South Park Is In Trouble And Needs To Change Course, Fast – yahoo.com

    South Park Faces Major Challenges and Must Adapt Fast to Survive

  • General
  • Health
  • News

    Cracking the Code: Why China’s Economic Challenges Aren’t Shaking Markets, Unlike America’s” – Bloomberg

    Trump’s Narrow Window to Spread the Truth About Harris

    Trump’s Narrow Window to Spread the Truth About Harris

    Israel-Gaza war live updates: Hamas leader Ismail Haniyeh assassinated in Iran, group says

    Israel-Gaza war live updates: Hamas leader Ismail Haniyeh assassinated in Iran, group says

    PAP Boss to Niger Delta Youths, Stay Away from the Protest

    PAP Boss to Niger Delta Youths, Stay Away from the Protest

    Court Restricts Protests In Lagos To Freedom, Peace Park

    Court Restricts Protests In Lagos To Freedom, Peace Park

    Fans React to Jazz Jennings’ Inspiring Weight Loss Journey

    Fans React to Jazz Jennings’ Inspiring Weight Loss Journey

    Trending Tags

    • Trump Inauguration
    • United Stated
    • White House
    • Market Stories
    • Election Results
  • Science
  • Sports
  • Technology
    China’s CATL sells stake in Finnish subcontract car manufacturer – Reuters

    China’s CATL Sells Stake in Finnish Auto Supplier in Strategic Move

    This Secret Technology Will Make The IPhone 17 Super Thin Air – VOI.ID

    How This Breakthrough Technology Will Make the iPhone 17 Incredibly Thin and Lightweight

    Gator football kicks off with excitement and new technology – WCJB | TV20

    Gator Football Kicks Off with Thrilling Action and Innovative Technology

    Marvell Technology (MRVL) Loses 18.6% as Growth Outlook Fails to Impress – Yahoo Finance

    Marvell Technology (MRVL) Loses 18.6% as Growth Outlook Fails to Impress – Yahoo Finance

    Propelling solar technology into a perovskite future – CORDIS

    Propelling solar technology into a perovskite future – CORDIS

    13 Top Technology Trends (2025) – Exploding Topics

    13 Game-Changing Technology Trends to Watch in 2025

    Trending Tags

    • Nintendo Switch
    • CES 2017
    • Playstation 4 Pro
    • Mark Zuckerberg
No Result
View All Result
  • Home
  • Business
  • Entertainment
    Country music star apologizes after drunken show ends with cops taking him down: ‘I’m not OK’ – PennLive.com

    Country Music Star Apologizes After Drunken Show Ends in Police Intervention: ‘I’m Not OK

    Comanche Nation Entertainment closes casino near Devol – KSWO 7News

    Comanche Nation Entertainment Closes Casino Near Devol in Surprising Move

    Erykah Badu Announces ‘Abi & Alan’ Album With The Alchemist Will Be Delayed – yahoo.com

    Erykah Badu Opens Up About the Delay of Her Highly Anticipated ‘Abi & Alan’ Album with The Alchemist

    If You Needed Some BTS Pics Of The Rock’s Tree Trunk Legs To Spice Up Your Day, We Got ‘Em – yahoo.com

    Need a Boost? Check Out These Epic BTS Shots of The Rock’s Tree Trunk Legs!

    Sabrina Carpenter’s pearl-clutching magic? Humor – CNN

    Sabrina Carpenter’s pearl-clutching magic? Humor – CNN

    South Park Is In Trouble And Needs To Change Course, Fast – yahoo.com

    South Park Faces Major Challenges and Must Adapt Fast to Survive

  • General
  • Health
  • News

    Cracking the Code: Why China’s Economic Challenges Aren’t Shaking Markets, Unlike America’s” – Bloomberg

    Trump’s Narrow Window to Spread the Truth About Harris

    Trump’s Narrow Window to Spread the Truth About Harris

    Israel-Gaza war live updates: Hamas leader Ismail Haniyeh assassinated in Iran, group says

    Israel-Gaza war live updates: Hamas leader Ismail Haniyeh assassinated in Iran, group says

    PAP Boss to Niger Delta Youths, Stay Away from the Protest

    PAP Boss to Niger Delta Youths, Stay Away from the Protest

    Court Restricts Protests In Lagos To Freedom, Peace Park

    Court Restricts Protests In Lagos To Freedom, Peace Park

    Fans React to Jazz Jennings’ Inspiring Weight Loss Journey

    Fans React to Jazz Jennings’ Inspiring Weight Loss Journey

    Trending Tags

    • Trump Inauguration
    • United Stated
    • White House
    • Market Stories
    • Election Results
  • Science
  • Sports
  • Technology
    China’s CATL sells stake in Finnish subcontract car manufacturer – Reuters

    China’s CATL Sells Stake in Finnish Auto Supplier in Strategic Move

    This Secret Technology Will Make The IPhone 17 Super Thin Air – VOI.ID

    How This Breakthrough Technology Will Make the iPhone 17 Incredibly Thin and Lightweight

    Gator football kicks off with excitement and new technology – WCJB | TV20

    Gator Football Kicks Off with Thrilling Action and Innovative Technology

    Marvell Technology (MRVL) Loses 18.6% as Growth Outlook Fails to Impress – Yahoo Finance

    Marvell Technology (MRVL) Loses 18.6% as Growth Outlook Fails to Impress – Yahoo Finance

    Propelling solar technology into a perovskite future – CORDIS

    Propelling solar technology into a perovskite future – CORDIS

    13 Top Technology Trends (2025) – Exploding Topics

    13 Game-Changing Technology Trends to Watch in 2025

    Trending Tags

    • Nintendo Switch
    • CES 2017
    • Playstation 4 Pro
    • Mark Zuckerberg
No Result
View All Result
Earth-News
No Result
View All Result
Home Science

Doubts Grow About the Biosignature Approach to Alien-Hunting

March 20, 2024
in Science
Doubts Grow About the Biosignature Approach to Alien-Hunting
Share on FacebookShare on Twitter

In 2020, scientists detected a gas called phosphine in the atmosphere of an Earth-size rocky planet. Knowing of no way that phosphine could be produced except through biological processes, “the scientists assert that something now alive is the only explanation for the chemical’s source,” the New York Times reported. As “biosignature gases” go, the phosphine seemed like a home run.

Until it wasn’t.

The planet was Venus, and the claim about a potential biosignature in the Venusian sky is still mired in controversy, even years later. Scientists can’t agree on whether phosphine is even present there, let alone whether it would be strong evidence of an alien biosphere on our twin planet.

What turned out to be hard for Venus will only be harder for exoplanets many light-years away.

NASA’s James Webb Space Telescope (JWST), which launched in 2021, has already beamed back data on the atmospheric composition of a midsize exoplanet dubbed K2-18 b that some have interpreted — controversially — as possible evidence of life. But even as hopes for a biosignature detection soar, some scientists are starting to openly ask whether gases in the atmosphere of an exoplanet will ever be convincing evidence for aliens.

A slew of recent papers explore the daunting uncertainties in exoplanet biosignature detection. One key challenge they identify is what the philosopher of science Peter Vickers at Durham University calls the problem of unconceived alternatives. Put simply, how can scientists be sure they’ve ruled out every possible nonbiological explanation for the presence of a gas — especially so long as exoplanet geology and chemistry remain nearly as mysterious as alien life?

“New ideas are being explored all the time, and there could be some abiotic mechanism for that phenomenon that just hasn’t been conceived of yet,” Vickers said. “That’s the problem of unconceived alternatives in astrobiology.”

“It’s a bit of this elephant in the room,” said the astronomer Daniel Angerhausen of the Swiss Federal Institute of Technology Zurich, who is a project scientist on the LIFE mission, a proposed space telescope that would search for biosignature gases on Earth-like exoplanets.

If or when scientists detect a putative biosignature gas on a distant planet, they can use a formula called Bayes’ theorem to calculate the chance of life existing there based on three probabilities. Two have to do with biology. The first is the probability of life emerging on that planet given everything else that’s known about it. The second is the probability that, if there is life, it would create the biosignature we observe. Both factors carry significant uncertainties, according to the astrobiologists Cole Mathis of Arizona State University and Harrison Smith of the Earth-Life Science Institute of the Tokyo Institute of Technology, who explored this kind of reasoning in a paper last fall.

The third factor is the probability of a lifeless planet producing the observed signal — an equally serious challenge, researchers now realize, that’s tangled up in the problem of unconceived abiotic alternatives.

“That’s the probability that we argue you can’t fill in responsibly,” Vickers said. “It could almost range from anything from zero to 1.”

Consider the case of K2-18 b, a “mini-Neptune” that’s intermediate in size between Earth and Neptune. In 2023, JWST data revealed a statistically weak sign of dimethyl sulfide (DMS) in its atmosphere. On Earth, DMS is produced by marine organisms. The researchers who tentatively detected it on K2-18 b interpreted the other gases discovered in its sky to mean that the planet is a “water world” with a habitable surface ocean, supporting their theory that the DMS there comes from marine life. But other scientists interpret the same observations as evidence of an inhospitable, gaseous planetary composition more like Neptune’s.

Unconceived alternatives have already forced astrobiologists multiple times to revise their ideas about what makes a good biosignature. When phosphine was detected on Venus, scientists didn’t know of any ways it could be produced on a lifeless rocky world. Since then, they’ve identified several feasible abiotic sources of the gas. One scenario is that volcanoes release chemical compounds called phosphides, which could react with sulfur dioxide in Venus’ atmosphere to form phosphine — a plausible explanation given that scientists have found evidence of active volcanism on our twin planet. Likewise, oxygen was considered a biosignature gas until the 2010s, when researchers including Victoria Meadows at the NASA Astrobiology Institute’s Virtual Planetary Laboratory began to find ways that rocky planets could accumulate oxygen without a biosphere. For example, oxygen can form from sulfur dioxide, which abounds on worlds as diverse as Venus and Europa.

Today, astrobiologists have largely abandoned the idea that a single gas could be a biosignature. Instead, they focus on identifying “ensembles,” or sets of gases that couldn’t coexist without life. If anything can be called today’s gold-standard biosignature, it’s the combination of oxygen and methane. Methane rapidly degrades in oxygen-rich atmospheres. On Earth, the two gases only coexist because the biosphere continuously replenishes them.

So far, scientists haven’t managed to come up with an abiotic explanation for oxygen-methane biosignatures. But Vickers, Smith and Mathis doubt that this particular pair — or perhaps any mix of gases — will ever be convincing. “There’s no way to be certain that what we’re looking at is actually a consequence of life, as opposed to a consequence of some unknown geochemical process,” Smith said.

“JWST is not a life detector. It’s a telescope that can tell us what gases are in the atmosphere of a planet,” Mathis said.

Sarah Rugheimer, an astrobiologist at York University who studies exoplanet atmospheres, is more sanguine. She’s actively looking into alternate abiotic explanations for ensemble biosignatures like oxygen and methane. Still, she says, “I would be popping open a bottle of champagne — very expensive champagne — if we saw oxygen, methane, and water and CO2” on an exoplanet.

Pouring drinks over an exciting result in private is, of course, different from telling the world they’ve found aliens.

Rugheimer and the other researchers who spoke to Quanta for this story wonder how best to talk in public about the uncertainty around biosignatures — and they wonder how swings in astrobiological opinion about a given detection might undermine public trust in science. They’re not alone in their worry. As the Venus phosphine saga moved toward a climax in 2021, NASA administrators and scientists implored the astrobiology community to establish firm standards for certainty in biosignature detection. In 2022, hundreds of astrobiologists came together for a virtual workshop to discuss the issue — though there’s still no official standard for, or even definition of, a biosignature. “Right now, I’m pretty happy that we all agreed, first of all, that this is a bit of a problem,” Angerhausen said.

Research moves ahead despite uncertainty — as it should, Vickers says. Running into dead ends and having to backtrack is natural for a fledgling field like astrobiology. “This is something that people should try to better understand about how science works overall,” Smith said. “It’s OK to update what we know.” And bold claims about biosignatures have a way of lighting a fire under scientists to falsify them, Smith and Vickers say — to go hunting for unconceived alternatives.

“We still don’t know what the hell’s happening on Venus, and so of course it feels hopeless,” said the astrochemist Clara Sousa-Silva of Bard College, an expert on phosphine who helped make the Venus detection. To her, the next step is clear: “Let’s think about Venus again.” Astronomers practically ignored Venus for decades. The biosignature controversy sparked new efforts not only to discover previously unconsidered abiotic sources of phosphine, but also to better understand our sister planet in its own right. (At least five missions to Venus are planned for the coming decades.) “I think that is also the source of hope for exoplanets.”

>>> Read full article>>>
Copyright for syndicated content belongs to the linked Source : Quanta Magazine – https://www.quantamagazine.org/doubts-grow-about-the-biosignature-approach-to-alien-hunting-20240319/

Tags: Aboutdoubtsscience
Previous Post

LISTEN | ‘Manufactured’ outages increase during vote counting: IEC

Next Post

Unlocking Ebola’s Secrets: The Ubiquitin Key to Halting the Deadly Virus

Construction of forest ecological security patterns based on MSPA model and circuit theory in the Desertification Control forests in South China Karst – Nature

Construction of forest ecological security patterns based on MSPA model and circuit theory in the Desertification Control forests in South China Karst – Nature

September 2, 2025
Bringing life science to life: Park Crossing teacher recognized – WSFA

Bringing life science to life: Park Crossing teacher recognized – WSFA

September 2, 2025
Take flight: EH seventh-graders learn science through paper airplanes – The Daily Reporter – Greenfield Indiana

Soar to New Heights: Seventh-Graders Explore Science with Paper Airplanes

September 2, 2025
Marcos orders lifestyle audit of all government officials — Dateline Philippines – Asian Journal News

Marcos Initiates Comprehensive Lifestyle Audit of Government Officials to Boost Accountability

September 2, 2025
China’s CATL sells stake in Finnish subcontract car manufacturer – Reuters

China’s CATL Sells Stake in Finnish Auto Supplier in Strategic Move

September 2, 2025
Mariners call up top catcher prospect Harry Ford, which could help Cal Raleigh late in season – Yahoo Sports

Mariners Elevate Top Catcher Prospect Harry Ford, Strengthening Cal Raleigh’s Late-Season Push

September 2, 2025
ECB’s Lagarde warns of risk to world economy via Trump interference on Fed – Reuters

ECB’s Lagarde warns of risk to world economy via Trump interference on Fed – Reuters

September 1, 2025
The Resilient Engine: Investing in Poland’s Outperforming Economy Amid Global Slowdown – AInvest

The Resilient Engine: Why Investing in Poland’s Booming Economy Is a Smart Move Amid Global Slowdown

September 1, 2025
Country music star apologizes after drunken show ends with cops taking him down: ‘I’m not OK’ – PennLive.com

Country Music Star Apologizes After Drunken Show Ends in Police Intervention: ‘I’m Not OK

September 1, 2025
Arts to promote mental health goal of new University of Michigan clinical program – MLive.com

Innovative University of Michigan Program Harnesses the Arts to Enhance Mental Health

September 1, 2025

Categories

Archives

September 2025
MTWTFSS
1234567
891011121314
15161718192021
22232425262728
2930 
« Aug    
Earth-News.info

The Earth News is an independent English-language daily published Website from all around the World News

Browse by Category

  • Business (20,132)
  • Ecology (802)
  • Economy (820)
  • Entertainment (21,700)
  • General (16,804)
  • Health (9,861)
  • Lifestyle (835)
  • News (22,149)
  • People (822)
  • Politics (828)
  • Science (16,031)
  • Sports (21,319)
  • Technology (15,801)
  • World (801)

Recent News

Construction of forest ecological security patterns based on MSPA model and circuit theory in the Desertification Control forests in South China Karst – Nature

Construction of forest ecological security patterns based on MSPA model and circuit theory in the Desertification Control forests in South China Karst – Nature

September 2, 2025
Bringing life science to life: Park Crossing teacher recognized – WSFA

Bringing life science to life: Park Crossing teacher recognized – WSFA

September 2, 2025
  • About
  • Advertise
  • Privacy & Policy
  • Contact

© 2023 earth-news.info

No Result
View All Result

© 2023 earth-news.info

No Result
View All Result

© 2023 earth-news.info

Go to mobile version