NASA researchers are working on a laser propulsion system that could get robots to Mars in 3 days
NASA researchers are working on a laser propulsion system that could get to Mars in 3 days
"There is no known reason why we cannot do this."
FIONA MACDONALD
22 FEB 2016
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NASA scientist Philip Lubin is working on a system where lasers propel spacecraft with giant sails to the Red Planet in as little as three days. Much like Bill Nye's much-hyped solar sail, this 'photonic propulsion' system relies on the momentum of photons - particles of light - to move forward. But instead of photons from the Sun's rays, Lubin's design would be given a push by giant Earth-based lasers.
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While Lubin and his team haven't yet tried out their system, their calculations show that photonic propulsion could get a 100-kg robotic craft to Mars in just three days.
A larger craft, like the kind humans might travel in, would take around a month to get there - one-fifth of the time it would take the Space Launch System (SLS), the world's most powerful rocket currently being developed to take us to Mars.
Lubin also explains that in the 10 minutes it will take to get the SLS into orbit, photonic propulsion could propel a spacecraft to an unheard-of 30 percent the speed of light - and it would also use a similar amount of chemical energy (50 to 100 gigawatts) to do so.
But the real benefit of photonic propulsion comes over longer distances, where the spacecraft has more time to speed up, and could eventually take us outside our Solar System and to neighbouring stars.
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= new reply since forum marked as read
The rocket equation applies for all propulsion. It's Newton's laws, basic physics. One does not get to wave ones hands and have it go away.
Why photonic propulsion is so efficient is that the propellent is going at light speed. It is better than VASIMR, which propels ions of Ar or Xe fucking fast, but not light speed.
It is the speed of the propellent that sets the maximum speed limit of the space craft. Yes, by the rocket equation.
There is no other way. Physics 101, my friend. Newton is in the driver's seat when traveling in space. It's not nice to fool Mother Nature. The rocket equation rules. Yes, even for light sails. Action results in an equal and opposite reaction kind of stuff. No way around that one.
My best to you.
Whether it is onboard or not, the same basic Newton's third law applies, momentum is conserved. That is what the rocket equation states.
I know I am probably being picky here, but the thrust has to come from somewhere. The LASER thrusting the sail will have an equal and opposite thrust. Momentum is conserved. The rocket equation technically still applies.
As always.
