• Question: Do you think that we are alone in this universe?

    Asked by Giller_98 to Colin, John, Kevin, Shikha, Triona on 7 Nov 2014. This question was also asked by 582bera34, jubril, ArnoldLAD.
    • Photo: Colin Johnston

      Colin Johnston answered on 7 Nov 2014:

      Short answer: I don’t know.

      Longer answer: it looks as though basically every star in the sky has planets of its own, that means there could be a 100 billion planets in our galaxy alone. It is hard to image that life has not arisen elsewhere, but we have no evidence yet. That’s why searching for life on nearby worlds like Mars is so important!

    • Photo: Tríona O'Connell

      Tríona O'Connell answered on 7 Nov 2014:

      If you’re referring to “intelligent life”, I don’t think we’ll get an answer to that in my or your lifetime, unless they travel to us (which I think is also unlikely but makes for great sci-fi). We’re pretty far from neighbouring stars and we’d hopefully have found such life already if it existed in the solar system.
      As for life that isn’t “intelligent”, the planet here is covered in all sorts of life. Whether nearby planets contain life, that’s what a lot of research is going into. the mars rover carries equipment to search for signs of life that may have existed in the past. Finding signs of early life on asteroids or other planets might give clues as to how life arose on Earth, or how common life might be.
      TLDR: we might not be alone, no way of knowing till we find some life or check every planet

    • Photo: Kevin Motherway

      Kevin Motherway answered on 7 Nov 2014:

      I thinks it’s a statistical improbability that there isn’t life out there: maybe 100,000,000,000 Galaxies with maybe 100,000,000,000 stars in each Galaxy with maybe 3 or 4 planets around each. That’s a pretty enormous number of chances for planets to be in the right zone for water to exists and life to evolve. The real question is though will that be green slime in a pond or walking talking beings with sophisticated culture or even space travel. But the problem is that Space is called Space for a reason, it would appear it’s mostly empty and the distances between stars and planets is huge. Our Galaxy is maybe 120,000 light years across, so if there is life out there even if you had a ship that could travel at light speed would you or your species live long enough to survive the journey to pop over and say hello. And that’s if life is conveniently in our Galaxy. To put in in Star Trek perspective the entire plot of Star Trek: Voyager is that they get magically transported to the other side or “delta quadrant” of the Milky Way farther away than anyone has ever travelled and they’re trying to get back home or the “Alpha quadrant”. In other words Star Trek is set in 100 Billionth of the entire universe. So it’s big. The chances for life are huge, but the chances we’ll ever run into each other or even communicate with each other are also equally massively against it happening. My head hurts for these numbers. I’m going to lie down now.

    • Photo: Shikha Sharma

      Shikha Sharma answered on 11 Nov 2014:

      Hi Giller_98,
      Till date we are the only living creatures in universe. Astronomers are tirelessly looking into every nook and corner of observable universe to find evidence of life. But nothing has been officially found. Though in almost all mythologies, we read the stories of superior life coming down to earth. Even many people believe some of the oldest great structural monuments e.g. Pyramid of Giza in Egypt, Nazca Lines in Peru, Stonehenge, Wiltshire, in England were made by aliens as human didn’t have such advanced technologies at that point of time. However, these are wild guess. We don’t have any scientific evidence to prove it.
      I guess we are not going to meet any neighbors from other planets soon. 😛