• Question: Do you think we will ever be able to travel beyond our solar system and discover new species?

    Asked by 349bera39 to Colin, John, Kevin, Shikha, Triona on 7 Nov 2014.
    • Photo: Colin Johnston

      Colin Johnston answered on 7 Nov 2014:

      Maybe. The stars are really far away. Let’s look the nearest star system to our own, the triple star system of Proxima Centauri, Alpha Centauri A and B which everyone knows is 4.36 light years away. “4.36 light years”, just rolls off the tongue, doesn’t it? Let’s convert 4.36 light year to kilometres, we get 41 trillion km. That sounds impressive, but just how big is a trillion? Start counting with me, a number every second, 1…2…3…4…

      When we get to 600, ten minutes will have passed. We get to 10,000 and two hours 47 minutes have gone by, keep going, don’t stop! A million seconds takes us 11.5 days. By the time we reach a billion seconds more than 31 years have gone by. Counting to trillion, a number every second takes more than 31 thousand years. A trillion is a ludicrously big number.

      The New Horizons probe is the fastest space vehicle made by humans so far. It was launched in 2006 and will get to Pluto in 2015.

      Let’s point the New Horizons probe at Alpha Centauri, start the clock and see how long it takes to get there. The journey will last 80 thousand years! And that is only the distance to the nearest star!

      Technology will improve and one day spacecraft will be faster, but we could still see voyages of centuries to nearby stars. Our robots will have to explore them for us!

    • Photo: Kevin Motherway

      Kevin Motherway answered on 9 Nov 2014:

      Voyager one and two have already left our solar system after about 30 years travel and are on the way through interstellar space.

      Are they on the right trajectory and will the last long enough to encounter life ? Highly improbable unless a passing vessel picks up their signal and flies to them.

      (Rest of my answer is from my answer to a similar question)

      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 349bera 39,
      Yes one day we will definitely travel beyond our solar system. NASA’s Voyager 1 satellite has already crossed solar system and still sending signals to us. No human being has traveled beyond solar system. But as science progresses mankind may travel through solar system in near future. But finding living species is just a chance. It is million time difficult to find a yellow marvel in desert of Sahara with a naked eye!!!!