Questions tagged [astrobiology]

The scientific study of the origin, evolution, distribution, and future of life in the universe.

Filter by
Sorted by
Tagged with
2 votes
1 answer
82 views

What factors allow some species to outcompete species formed by the local environment and become invasive?

If an invasive species is introduced to a new environment, why can they outcompete local species in the same nische, if they specifically evolved in this local environment and are adapted to it, ...
Qoray's user avatar
  • 153
5 votes
2 answers
93 views

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 ...
SE - stop firing the good guys's user avatar
16 votes
2 answers
2k views

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 ...
dashnick's user avatar
  • 279
0 votes
2 answers
114 views

Have we found any other life form outside our planet?

I'm not asking about the possibility of formation of life on other planets instead has there been any real evidence of life(such as micro organisms or even very basic structures) that might suggest an ...
Matt's user avatar
  • 11
2 votes
1 answer
128 views

Could biofilms float and survive in the sulfuric acid clouds of Venus?

The atmosphere of Venus is composed of 96.5% carbon dioxide, 3.5% nitrogen, and traces of other gases, most notably sulfur dioxide. The main cloud deck is located in the 48-70 km altitude range and is ...
Cornelis's user avatar
  • 145
0 votes
0 answers
53 views

life based on different elements [duplicate]

It is commonly proposed to look for life based on silicon, based on it's relative abundance and similarity to carbon. However, carbon and silicon are not completely interchangeable. The bond strength ...
Qoray's user avatar
  • 153
0 votes
1 answer
69 views

Is this panspermia mechanism feasible?

One episode of Cosmos: A Spacetime Odyssey describes a mechanism by which microbes could travel between planetary systems. As a star's orbit takes it around the galaxy, it occasionally passes through ...
J.G.'s user avatar
  • 2,474
8 votes
2 answers
226 views

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 ...
Real's user avatar
  • 154
1 vote
0 answers
37 views

How, when, and where did the very first life in the universe exist/formed [closed]

Do we know about the very first life, how it is formed? or from where it originated in the universe? How life is fromed in our planet earth?? Life require conditions for survival or it can create ...
Rithik's user avatar
  • 11
2 votes
3 answers
402 views

Is designing alien life still just science fiction?

As we continue to search for life in very different environments than the earth, it would make sense to me to think about and design lifeforms (theoretical) that could work in these environments. I ...
macco's user avatar
  • 262
1 vote
0 answers
54 views

Martian Abiogenesis?

In the Miller-Urey experiment the probability of the chemical origin of life under (hypothetical) early Earth atmospheric conditions were assessed. For that water, methane, ammonia, and hydrogen were ...
diligar's user avatar
  • 111
1 vote
0 answers
43 views

What are the tests performed by NASA's Mars rovers to establish that life could survive on the planet?

I am particularly interested in the Mars Rovers, which are out there trying to find life. Do they believe that the tests they perform are sufficient to verify the existence of life (Also please ...
Manish's user avatar
  • 111
0 votes
1 answer
86 views

What is the reasoning behind the Drake Equation?

I've read a bunch on how the Drake Equation is constructed, but I'm not able to understand some of the reasoning behind it. $$ N = R_* \cdot f_p \cdot n_e \cdot f_l \cdot f_i \cdot f_c \cdot L \cdot ...
Adam's user avatar
  • 111
8 votes
1 answer
825 views

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 ...
Nerrolken's user avatar
  • 977
0 votes
1 answer
110 views

Is it possible for humans to digest and live on food that isn't based on DNA or RNA? [closed]

Our bodies digest food using enzymes that have evolved to convert food here on Earth. Could we even possibly get nutrients from something we haven't evolved alongside? - Is it possible for humans to ...
Jordan's user avatar
  • 119
4 votes
1 answer
355 views

A colony of humans are sent to an alien world, at what point would the descendants evolve to be genetically incompatible with Earth humans? [closed]

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 ...
timgcarlson's user avatar
3 votes
1 answer
71 views

How much divergence would be needed for classifications as astrobiology?

It is possible that life has invaded mars or the moon by way of probes rovers and other man made tech. How many years or generations of sequential and phenotypical diverge would be necessary to ...
user avatar
4 votes
1 answer
156 views

Life on other planets [duplicate]

first of all I'm not sure if I should post this here or in the astronomy stack. I think biologist are more likely to answer my question. To make it short: Why when looking for any sort of life on ...
Mehdi's user avatar
  • 245
3 votes
1 answer
163 views

What would classify those findings of the University of Sheffield experiment as aliens?

It's in the news that some experiment was able to capture some alien specimens during a meteor shower: http://www.ibtimes.com/aliens-are-here-scientists-say-they-have-proof-alien-life-there-should-be-...
woliveirajr's user avatar
3 votes
1 answer
105 views

In our solar system which other planet could have been in the "habitable zone" in the past?

With changes in our solar system, such as planets moving away from the sun and the reduction in solar radiation, which other planets in our solar system could have been, in the past, in a suitable ...
Ram Manohar M's user avatar
12 votes
2 answers
303 views

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 ...
Drosophila's user avatar
  • 1,538
8 votes
1 answer
252 views

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 ...
Daniel's user avatar
  • 261
6 votes
1 answer
998 views

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, ...
Cat's user avatar
  • 238
9 votes
2 answers
107 views

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 ...
Everyone's user avatar
  • 3,863
10 votes
2 answers
433 views

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 ...
Lorenz Lo Sauer's user avatar
9 votes
3 answers
297 views

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 ...
Brian's user avatar
  • 201
11 votes
2 answers
457 views

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 ...
LanceLafontaine's user avatar
32 votes
4 answers
6k views

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's user avatar
  • 3,006
27 votes
2 answers
880 views

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 ...
Poshpaws's user avatar
  • 7,292
21 votes
1 answer
402 views

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 ...
Poshpaws's user avatar
  • 7,292