Questions tagged [life]

Questions regarding life in the universe, especially the possibility of life outside our planet, or the influence of astronomical forces on life on Earth.

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31
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2answers
2k views

Could any known, living organisms on Earth survive on Mars?

No life has been discovered outside of Earth (yet?), but do we know if anything that would be considered "living" on Earth could conquer Mars? (or maybe Venus?) With the Mars One project on the way, ...
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6answers
26k views

What will happen to life on Earth when the Andromeda and Milky Way galaxies collide?

It is said that the Andromeda and Milky Way galaxies are coming close to each other with a speed of approximately 400000 km/hour. They will be together in the next 4 billion years. What will happen ...
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3answers
3k views

how far away could we detect that Earth has life?

My guess is that life bearing planets are too far apart to be detected. I think we can only find the ones within a sphere around our planet that is 100s of light years in diameter but I suspect life ...
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2answers
1k views

Whats the probability of a hazardous impact for human life on Mars?

Yesterday my sister and I have discussed the recent efforts of SpaceX to create a permanent colony on mars. When coming to the several dangers of creating a habitat on a different planet, we got ...
18
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2answers
3k views

How many planets have we discovered that can support human life?

I have heard a lot of buzz about distant planets that could potentially be second homes for human existence, but what is that approximate number?
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4answers
2k views

Why is liquid water considered a requirement for life?

I`ve heard about different extremofiles living on earth. Is water a requirement for life because we have not seen life survive on earth without it, is it a chemical reason which makes life without ...
15
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1answer
328 views

Any possibility for life on moons of planets in our Solar System

We all focused on our moon, to find water or life, or any thing related to life. But my question is, is there any chance for life in moons of other planets in our solar system, others have too many ...
14
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2answers
363 views

What earth organisms would survive if they arrived on Mars?

Contaminating other planets is a concern in space exploration. My question is what organisms, or small collections of organisms, from earth would be able form a self-sustaining population on Mars? I'm ...
14
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4answers
911 views

If we found evidence of life on Mars, how would we know that it originated on Mars rather than Earth?

Consider this scenario. One of the probes sent to Mars either very soon, or within the next century, finds conclusive micro-fossil evidence that life once existed on Mars. One theory today that is ...
12
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1answer
141 views

Is it possible to observe if there is traces of life on an exoplanet?

We can observe exoplanets, but is it possible with today's technology to observe if there is life as we know it on an exoplanet? What do you look for when doing this kind of observation?
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Method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle? [closed]

What is the method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle? (Not from occlusion but actually visible on its own.) Further, ...
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3answers
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Life planets orbiting black-holes. Can/Do they really exist?

So, I watched Interstellar and if you watched it too you know that there's a planet orbiting a black-hole, they call it Miller's Planet. According to the movie, every hour on Miller's Planet is ...
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3answers
297 views

Is there anything special about our position in the galaxy thats necessary for life?

It's a fact that our planet's location from our parent star (among other factors) is of crucial importance to the existence of life. But can our position in the galaxy be considered a factor when ...
9
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3answers
685 views

Do we expect life to develop only in certain regions of the galaxy?

If I understand correctly, the Earth lies in an area of the galaxy - the "local bubble" - that is relatively free of dust and gases and where no new stars are being born. What is the current theory ...
8
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1answer
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How likely and severe is the threat of a gamma ray burst to earth?

In the National Geographic article: http://news.nationalgeographic.com/news/2009/04/090403-gamma-ray-extinction_2.html it is suggested that a gamma ray burst likely caused a mass extinction in earth's ...
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6answers
227 views

Evolution of Life

Since life evolved here on Earth does that mean that life had to have existed before or in the future elsewhere in the Universe or could it be a one time only freak accident ?
6
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1answer
249 views

What is the underwater temperature of Europa?

If Europa has an oxygen atmosphere with a water mantle, is it possible that there could be life under the crust of Europa ice on the ocean where it is warmer? What could be the temperature under the ...
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5answers
243 views

Could there be life beneath the surface of Mars or moons?

I realize radiation and extreme temperatures would probably destroy life on the surface of most planets and moons, but could life exist beneath the surface (e.g. like earth worms on earth)?
5
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1answer
203 views

Proxima as Supernova

Follow this question. If a star at the same distance from us as, say, Proxima Centauri had exploded as a Supernova 4 years ago (I know, it can't explode as supernova, let's say it can)... How bright ...
5
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1answer
138 views

Will the conditions that allow life to evolve still be around in a trillion years?

Some billions of years ago, systems like the Earth couldn't emerge and therefore life couldn't arise, because not enough of the heavy elements had formed yet. Assuming there'll neither be a big ...
5
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1answer
572 views

Why are ice giants not considered suitable for life?

Ice giants are currently not considered suitable for life due to temperature, pressure and composition. This paper gives some parameters for life in regards to temperature, pressure and composition: ...
5
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2answers
375 views

Would being ejected from the Milky Way Galaxy have any major impact on life on Earth? [duplicate]

I was reading about the impending collision of our galaxy with the Andromeda galaxy, and learned that there is a small possibility that our solar system could be ejected during the collision. ...
4
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2answers
904 views

Would a Phobos full impact make Mars temporary habitable?

Due to tidal deceleration, Phobos is predicted to be destroyed by Mars in the next 30-50 million years either by collision or by breaking up in a planetary ring. If Phobos falls on Mars in one piece ...
4
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2answers
242 views

Has life been discovered outside of Earth?

I've just watched a movie that made me curious as to whether life has really been discovered on another world such as Europa??
4
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1answer
376 views

Do all stars have the potential to have life supporting planets?

Regardless of how big or small, how hot or cold, do all stars have a goldilocks zone, and if so, could any given planet in this zone (with the right configuration) support life?
4
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1answer
131 views

How early could life supporting planets been formed?

In thinking about exclusion options for where its not worth to look for habitable planets, the past came to my mind. Right at the beginning of the universe, there was no possibility for (carbon based)...
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2answers
326 views

What if we are looking for the wrong signs of life on other planets?

I am by no means an astronomy expert, having only taken 2 semesters in college. But I am an avid follower of news reports that look for signs of life on other planets. Today it was announced that 20 ...
3
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4answers
247 views

Could the solar system survive in a void?

If the solar system were suddenly placed in the middle of a large void... would everything still function as normal? Would we even notice any difference here on Earth apart from the night sky? ......
3
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2answers
637 views

Why do scientists think life requires water? [duplicate]

As far as I know, scientists seeking extraterrestial life are simply looking for plantets containing water in liquid state. To be honest, I find this weird. It is true that life - in the form we know ...
3
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1answer
135 views

The Solar System formation

I've recently watched one conversation (I won't post a link since the conversation is not in english) involving a physicist (at least he claims so), who spoke about probabilistic estimates of the ...
3
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2answers
141 views

Consequences of strong wind on an alien Planet on the possibility of life

I was surprised to learn recently that Neptune has winds of 1500 miles an hour. My question is whether life could ever evolve on such a Planet that has such powerful winds? Not necessarily on ...
3
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3answers
157 views

Plant on large Asteroid?

I'm just curious if it is possible for a plant to survive on a large asteroid. Some say no, some say it depends. With the scenario of an asteroid at about 1 AU from the Sun, receiving a similar ...
3
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2answers
280 views

Can life survive on the equator of cooled and fast rotating white dwarf or neutron star?

As I know, some stars produces carbon, nitrogen and oxygen when they are old and become white dwarfs or neutron stars. And even their surface gravity is strong, it may rotate very fast so that the ...
3
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1answer
283 views

Does liquid water on Mars means life?

We need to figure if liquid water is present throughout a Mars year, and how long the planet has been at its current distance from Sun. That will give us the length of time that liquid water has been ...
3
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1answer
73 views

Other than liquid water what factors could make way for life to be on Europa?

I know that Europa has liquid water, but I just don't know if there is anything else on it that could give way for life.
3
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1answer
236 views

Is there enough light to grow plants in the ocean of Europa?

What is the underwater temperature of Europa? I know Jupiter emits infrared light but does it emit any light able to support plant life of any type on near by Moons? Can under water volcanic activity ...
3
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3answers
2k views

How close would the sun have to get to Earth for there to be severe consequences?

According to earthsky.org the Earth gets 3 million miles closer to the Sun than its usual distance of about 93 million miles on average. My question is, how close would the earth have to be to the ...
3
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1answer
147 views

Why did Earth need material from comets to assemble the raw materials for life?

It's often speculated that matter from comets played a crucial role in the development of life on Earth. For example, Maps of Time says, Many of the ingredients of the early atmosphere (including ...
3
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1answer
1k views

Could human life thrive on a planet in a pulsar star system?

Aleksander Wolszczan of Pennsylvania State University found three planets circling a pulsar called PSR B1257+12.Two of the planets were the size of Earth.The pulsar observed by Spitzer, named 4U 0142+...
3
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1answer
267 views

Available energy for potential life on Titan

There is an interesting discussion about whether there could be life on Saturn's moon Titan. (For example here.) The life could use reaction of hydrogen and acetylene which are being produced by ...
3
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0answers
64 views

How strong are the stellar flares on YZ Ceti?

Doing research for a game and trying to understand the implications of the stellar flares from YZ Ceti. In short (ignoring the planets for now), if people were to build large space stations of various ...
2
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1answer
299 views

What is the probability that there is life on other planets?

From a mathematical point of view, what is the probability that 1) There is organic life on other planets 2) There are advanced species like us or even greater than us on other planets? Is there ...
2
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4answers
214 views

Why haven't detected life in the universe?

It would seem that if life were relatively common in the universe that there would be a cacophony of noise somewhere in the electromagnetic spectrum. Is life so rare and distant that the waves haven't ...
2
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2answers
229 views

What planets and moons have we seeded with life (if any)?

Which planets and moons have we accidentally (or purposely) seeded with life? I would expect this to be any planet or moon we have sent an unsterilized (or not fully sterilized) lander to, or crashed ...
2
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2answers
185 views

Explaining the Drake Equation on a smaller scale

So me and my friend were planning a video to explain the Drake Equation (within a time limit of 5 minutes), and we needed some help. This video is aimed at explaining the concept to an age group ...
2
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1answer
151 views

Red dwarf variation in Luminosity

I recently saw this video. The creator of the video says that one of the reasons for non-existence of life on planets around red dwarfs might be that these stars can increase luminosity roughly by a ...
2
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4answers
493 views

Notable differences if all stars would disappear except the Sun

I am not an astronomy expert, but as of today, all other stars than the Sun have little to no effect on life on Earth. So I was thinking, would there be any differences for the Earth at all if all ...
2
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1answer
112 views

Could an Earth-like magnetic field protect life at exoplanet Proxima Centauri b?

I took a look at Wikipedia's page for Proxima Centauri b, the exoplanet that orbits Proxima Centauri, where it is said it is expected to receive 2000 times of stellar wind pressures than on Earth. It ...
2
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2answers
374 views

How does space time differ within a galaxy?

Not the same question but is similar to other marked duplicate. How much time dilation does the center of a galaxy can exist and sustain human life from our point of view? What would a day equal to ...
2
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1answer
80 views

Probability of finding life-supporting exoplanets

We've found over a thousand exoplanets by now, but how many of them could support life? What percentage of newly found planets are potentially life-harbouring? Or haven't we found any exoplanets that ...