ok, you are right;) I was to hasty, sorry:((
Here http://www.pioneerastro.com/USSIT/ussit.html is the original paper on which NASA is referring. It explains much more. Still, it states that anything less then 10 m/s^2 is unpractical for the interstellar flight.
These solar sails are pretty useless. Here http://solarsails.jpl.nasa.gov/introduction/design -construction.html
are calculations from NASA guys. It looks like this
Japanese sail has acceleration of few mm/s^2 and is not able to get out of sun gravitational field (and, of course, the Earth's one). It would take solar sail 100 years to get
to alpha centauri if it had acceleration 10 m/s^2 (table 3 in the above link, there is "-" in the
table for 5 m/s^2 and less , that is it will never get away from sun ).
There was a good idea though to build a huge mirror to focus sunlight on such sail. This would effectivly increase surface area of a sail and
pressure would not drop as square of the distanse from the sun.
Slashdot Mirror
ok, you are right ;) I was to hasty, sorry :((
Here http://www.pioneerastro.com/USSIT/ussit.html is the original paper on which NASA is referring. It explains much more. Still, it states that anything less then 10 m/s^2 is unpractical for the interstellar flight.
These solar sails are pretty useless. Here http://solarsails.jpl.nasa.gov/introduction/design -construction.html
are calculations from NASA guys. It looks like this
Japanese sail has acceleration of few mm/s^2 and is not able to get out of sun gravitational field (and, of course, the Earth's one). It would take solar sail 100 years to get
to alpha centauri if it had acceleration 10 m/s^2 (table 3 in the above link, there is "-" in the
table for 5 m/s^2 and less , that is it will never get away from sun ).
There was a good idea though to build a huge mirror to focus sunlight on such sail. This would effectivly increase surface area of a sail and
pressure would not drop as square of the distanse from the sun.