posted on Aug, 3 2016 @ 07:52 AM
There is an interesting (and quite detailed) paper on near term feasibility of laser sail systems for interplanetary and interstellar travel.
According to their calculations a small ~1g probe could reach Alpha Centauri in 15 years, at 0.26c speed, driven by a 70GW laser system. The same
system could get a 100kg probe to 0.11c. So it scales pretty decently with increasing mass.
There one minor handicap though. Those would be pure flyby missions. You simply can not afford to carry the massive amounts of fuel required to slow
down from those velocities. So how do we deal with that?
One idea has been to use a magnetic sail. Unfortunately magnetic sail force drops asymptotically with the velocity. The slower you go the lower the
deceleration. Slowing down to orbital velocities would take way too long.
More recently an electric sail has been proposed, which works better at low velocities. Although it requires an energy source to keep the sail
There is a paper looking into combining both ideas and using a magnetic sail as the first stage followed by the electric sail to get down to orbital
With a magnetic sail limited to 50km ring radius (material constraints) their example spacecraft (8250kg total) would take 300 years to decelerate
from 0.05c and would buzz past Alpha Centauri. The combined system reduces this time to 28.8 years, or 0.6 light years deceleration distance. They
didn't look at low mass probes. But I assume those should perform as well if not better as the magnetic sail radius constraint is less of an issue.
Imho combined laser/magnetic/electric sail systems could well be the future of interstellar exploration and travel, especially combined with
My preferred idea for large masses (humans) would be to install a laser driver in the target system to take care of the deceleration issue. It could
maybe even be constructed in situ by bots sent in advance. But that might be a not so near term solution.
edit on 3-8-2016 by moebius because: (no reason given)