• Question: is there life in the galaxy.

    Asked by vast499kay on 8 Feb 2024. This question was also asked by area499kay.
    • Photo: David Bremner

      David Bremner answered on 8 Feb 2024:

      I know relatively little about space so am not sure i can answer this, but what we know about this is probably far less than the number of questions we still have about it.

    • Photo: Bruno Silvester Lopes

      Bruno Silvester Lopes answered on 8 Feb 2024:

      I don’t think so.

    • Photo: Alexander De Bruin

      Alexander De Bruin answered on 8 Feb 2024:

      I believe so, we just haven’t found it yet. The galaxy and the universe are so big that it would be odd if life wasn’t out there. The life that is out there, however, may be completely different than the life we find on earth

    • Photo: Ben Dryer

      Ben Dryer answered on 8 Feb 2024:

      This is a tough one! We haven’t found any yet, but our sun is one of 100,000,000,000 stars in the galaxy, that’s such a huge number it’s harder for me to believe that we are the only life out of all those stars rather than we are unique. We have only been able to look in such a small pocket of the galaxy that it seems inevitable that the same conditions of Earth are out there somewhere and life could have appeared. Missions like JUICE and Europa Clipper are going to Jupiter to look for signs of life in the liquid water under the icy surface of its moons, and might be our best bet of finding an answer in the next 10 years or so.
      If we find the conditions of life on Jupiter, we know that Jupiter-like planets are quite common around other stars, so it would have wide-reaching implications for the possibility of life around other stars.

    • Photo: Andrew McDowall

      Andrew McDowall answered on 8 Feb 2024:

      Technically, yes, but so far we’ve only found it on this planet. Astronomers are searching hard for signs of life elsewhere and their ability to search is steadily increasing with some exciting new technology expected in the next few years.There’s also continued research into the conditions life can exist in and what are the chemical signs that only life can create that we might be able to look for elsewhere.

      On Earth, it appears life can exist almost anywhere there’s liquid water. The raw materials of life can be found abundantly in the galaxy but the circumstances under which they’re assembled to move from being geologic to biologic are unknown at the moment. It’s unclear if life needs a specific set of circumstances to get started, after which evolution can get to work enabling life to exploit those more challenging environments in which liquid water exists; or whether life can emerge anywhere there’s liquid water, the required chemicals, and a viable source of energy to use. How life gets started will have a big impact on the number of places and the environments in which life could be found elsewhere in the galaxy. Finding, or failing to find, life in the different environments water exists in our solar system will help answer some of these questions.

      Unfortunately geology and biology only have access to one chemistry, so finding signs of life that couldn’t be signs of geology (certain chemicals, preference for certain different weights of atom or only one of two or more mirror image chemicals and so on) is quite difficult. The report of finding phosphine (PH3) in the clouds of Venus in 2020 is a good example of this problem. When first announced, it was claimed as a possible indication of life, then of geology, now it’s doubted to be there at all.

      We are a little hamstrung by only having one example of what life is and how it works but we are, at least, looking.

    • Photo: Rachel Edwards

      Rachel Edwards answered on 8 Feb 2024:

      Astronomers are finding so many planets orbiting around different stars, so there must be life somewhere! It is likely to be very different from life on earth though.

    • Photo: Martin McCoustra

      Martin McCoustra answered on 8 Feb 2024:

      The physical and chemical processes that form stars and planets, and produced the primordial chemical soup from which life evolved are pretty much the same everywhere in the Milky Way. There is every chance that life might have evolved somewhere else within our galaxy. The question is can we find it out there and astronomers are gearing up to address that question.

    • Photo: Michael Schubert

      Michael Schubert answered on 8 Feb 2024:

      We have no proof that there is life anywhere else in the galaxy yet, but we have seen some signs that could potentially suggest life. This is a hard question to answer, though, because if we find life, we’ll have proof that it exists – but if we don’t, we can’t prove that it doesn’t exist somewhere we haven’t looked yet.

      With so many different stars, planets, and possibilities, though, we have to think about what life might look like in a completely different environment and how we might recognise it. Life is so diverse even on Earth that it might look very different on another planet to anything we can imagine right now!

    • Photo: Vicky Fawcett

      Vicky Fawcett answered on 8 Feb 2024:

      Short answer: we don’t know, we haven’t found it yet!

      However, there are roughly a billion stars in every galaxy and roughly a billion galaxies in universe. We also know that it is very likely for a star to host a planet, potentially multiple planets per star, and so 1 billion x 1 billion x let’s say 1 planet = 1,000,000,000,000,000,000 (or 1 quintillion) planets in the universe!!
      That’s a lot of planets! Therefore it’s very unlikely that our planet is the only one that hosts life.

      We have also discovered many planets that look very similar to the Earth, orbiting stars that look very similar to the Sun. Maybe one of them is similar enough that it also hosts life…

    • Photo: Kirsty Ross

      Kirsty Ross answered on 15 Feb 2024:

      I hope so. I don’t think we are alone in the universe, but it is unlikely that we will ever meet a species like us. The distances involved are too great.

    • Photo: Sheridan Williams

      Sheridan Williams answered on 27 Mar 2024:

      Almost certainly depending on your definition of life. If your question was “is there intelligent life” that is a different matter, and also depends on your definition.
      However, why limit your question to the galaxy? Be aware that there are billions of galaxies.