The scientific study of the origin, evolution, distribution, and future of life in the universe.
The scientific study of the origin, evolution, distribution, and future of life in the universe.
Questions tagged [astrobiology]
29 questions
32
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4 answers
What is the lowest pressure at which plants can survive?
What is the lowest pressure at which plants can survive? How the plants behave in a Martian-type atmosphere? Is there any plant that can survive such atmosphere?
Can a lichen grow at Martian pressure?
Anixx
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How do biological communities at deep-ocean hydrothermal vents migrate between vents?
Much interest in the astrobiology community has been generated by the discovery of biological communities populating deep-ocean hydrothermal vents (i.e. "black smokers"). (1) These ecosystems rely on chemoautotrophic bacteria/archaea extremophiles…
Poshpaws
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Is there any convincing evidence for the existence of nanobacteria?
The existence of nanometer scale microorganisms has been proposed and used explain several phenomena including morphological structures in a martian meteorite (ALH 84001) and implication in the formation of kidney stones (1).
Is there now any…
Poshpaws
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16
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How is it thought that phosphine is synthesized by living organisms on Earth?
The recent (Sept. 2020) report of “Phosphine gas in the cloud decks of Venus” states that phosphine (PH3) is only known to occur on Earth due to anaerobic life. Quoting from a report in the New York Times:
But scientists have yet to explain how…
dashnick
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Can life subsist on anything else but water?
Inspired by an answer to a previous question.
It's hypothesized that extraterrestrial life could be based on silicon rather than carbon as its main structural element.
Are there similar theories about an alternative "life solvent" rather than water?…
Drosophila
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How did the nucleobases in the Murchison meteorite form?
The Murchison meteorite is an important piece of evidence for abiogenesis, because it contained nucleobases from extraterrestrial origin, as this Wikipedia article explains.
These results demonstrate that many organic compounds which are components…
LanceLafontaine
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Is there life on other planets and if so how frequent?
Some shed tears of joy as the news about the successful landing of the Mars Rover Curiosity came in. Then the most comprehensive 3D map of our observable universe was published. 2012 is literally an astronomical year.
As an layman I would like to…
Lorenz Lo Sauer
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What would need to be discovered to prove there is extraterrestrial life?
Curiosity is on the Martian surface and is equipped with a slew of laboratory equipment. What would Curiosity need to discover to prove there is or has been life on Mars? Would it have to find DNA (or its Martian equivalent)?
Brian
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Why must a planet be in a star's "habitable zone" to have life?
I have seen many articles that talk about a star's "habitable zone" as the ring around it which is just the right temperature for planets to have liquid water, which is necessary for life. My question is, why does a planet need to have liquid water…
Daniel
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Would current-day human-initiated panspermia be effective?
With current technology, we are able to easily send a probe to the Alpha Centauri star system at a speed of about 20 km/s (velocity of voyager probe), which means it would take about 65000 years to get there.
In light of this, suppose we sent a…
Real
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Should we be looking for extra-terrestrial life on comets?
I have just read What elements are a possible basis for life? and I find myself wondering whether instead of seeking advanced life-forms at remote locales a La SETI, and perhaps fundamentally differently, we ought to be looking for similar…
Everyone
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What is the highest pressure at which plants can survive?
Inspired by this awesome question, I'm looking for the corresponding maximum: what is the highest air pressure at which plant life can survive?
For example, Venus's atmosphere is about 90x as dense as Earth's. Aside from the other obvious…
Nerrolken
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If life is discovered on another planet, will it likely be classified using the current domain/kingdom/phylum system?
This may be a stupid question showing my lack of understanding of taxonomy, but I was wondering if the current classification system we use contains broad enough categories to include new life forms, if they are discovered on other planets? Would…
Cat
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How correlated is the chirality of different molecules?
In astrobiology, a proposed way of testing whether life found on another world is alien or originates from Earth is to determine the chirality of its molecules. This is of course only useful when the biochemistry is similar enough that one may…
4
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A colony of humans are sent to an alien world, at what point would the descendants evolve to be genetically incompatible with Earth humans?
I recently heard about the evolution of the London Underground mosquitoes, and how they have changed genetically enough that they almost can no longer reproduce with above ground mosquitos. Since this change in the mosquitos occurred over a…
timgcarlson
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