• Tris Mamone wrote a new post, What it would take to reach the stars 3 years, 5 months ago

    By Gabriel Popkin

    Anybody who longs to see an alien world up close got an exciting gift last year. In August, researchers reported the discovery of a potentially habitable, Earth-sized planet orbiting the […]

    • So if we land something on that planet and it’s occupied, will it screw up the Centaurian religions or will their apologists insist it was sent by their god to prove his existence? “Our Father who art on Earth…”

    • Could you use Proxima Centuri’s Sun to slingshot it back or would it have to get too close. The problems are eminence when you thing about it, the sail would be effected by the solar wind while in the solar system, and the solar wind of Proxima Centuri would also influence it, any tiny fluctuation would blow it off course by an enormous amount. With no ability to steer it’s just shoot and hope for the best. Still, interesting.

    • Reckless Monkey #5
      Feb 6, 2017 at 1:13 am

      Could you use Proxima Centuri’s Sun to slingshot it back or would it have to get too close.

      The proposed velocity would simply be too high to make a 180° turn using a star’s gravity.
      Any deflection from passing at a safe distance, would be too small.

    • Thanks Alan4discussion,

      Sounds like they’d really need some sort of course correction also. All very difficult. Still thinking at the fringes will often give benefits even if not directly for this project.

    • @maria melo

      How to figure out then a way for humans to travel there if it had similar conditions to Earth (“travel in an envelope”).
      Exciting, but a too far future it seems.

      Humans become exponentially more tricky for a number of reasons. 1) no one wants to really be accelerating for any period of time at greater than 1 G. The advantage of constant acceleration at 1 G is that it would give artificial gravity. And half way there you turn around fire the engines and decelerate at 1G for the remainder of the journey. This little electronic chip would be able to accelerate at much higher rates because it is made of things that are not soft and squishy (although I do not know what rate the solar sail is accelerating the device at – however the longer to accelerate the harder it is going to be to focus lasers on a 4 meter sail, so I’m assuming the mean to do so fairly rapidly (without melting the sail). There were proposals ages ago for nuclear powered space craft one would take hydrogen from space and use it run the fusion engines that fire the craft forward meaning no fuel needs to be carried. However you need something like a kilometer wide funnel to channel the extremely sparse hydrogen. No to mention at the speeds we a talking about any speck of ice of rock would cause enormous damage so you would need something to zap any incoming dust particles etc. The powered required would be enormous. But I’d still like to see us pursue the goal I think it would do us a world of good.

      Just looked it up not 1 km across about 100 km across!

      worth watching this though will blow your mind.

    • @ Alan4Discussion,

      We need to get self assembling machines going as soon as possible then certainly mining asteroids and manufacturing in space would be needed for anything like the scales we’re talking about here. It’s hard to fathom how far away this all looks but there was a great bit in “In the Shadow of the Moon” where one of the Apollo Astronauts was explaining how his father born at the turn of the century around the time of the Wright Brothers could barely believe they’d gone to the Moon but that his son who as 5 at the time thought it was no big deal.

    • Reckless Monkey #11
      Feb 9, 2017 at 6:24 am

      The power required would be enormous.

      The evolving Icarus probe designs come in several variations using different sizes of probe and different forms of fusion drive.

      The variants are called: Firefly. Ghost, Resolution, Endeavour, Zeus, and UDD.

      Deuterium and Helium 3 (or Tritium) are the suggested fuels. – injected into the engines in pellet or gas form according to the variant of engine design.

      The plan is not for a flyby, but to turn the craft 180 degrees and decelerate before releasing a nominal payload of 100 to 150 tonnes of science probes in the chosen Centauri system.