#### SH

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« on: 05/02/2015 01:43 pm »
I'm curious about the practical trajectories that might be used by a solar sail to make interplanetary or even interstellar travel -

(1) assuming solar pressure is the sole source of propulsion, what do the ideal (fastest) trajectories look like for going to various other planets in the solar system?  It seems like an interesting problem because your thrust vector must always be within 90 degrees of the vector to the closest star.  I imagine for longer range missions, you'd want to fall close to the sun and then slingshot out, whereas for closer missions you'd just go directly, but not sure where this practical threshold lies.  I'd love to see some pictures of the most efficient ways to get to each planet in the solar system.

(2) For the purpose of interstellar travel, it seems that the velocity would eventually asymptote at some value dependent on sail size.   Is this maximum velocity well quantified?
« Last Edit: 05/02/2015 02:41 pm by SH »

#### scienceguy

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##### Re: Curious about solar sails
« Reply #1 on: 05/02/2015 05:30 pm »
e^(pi*i) = -1

#### Raj2014

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##### Re: Curious about solar sails
« Reply #2 on: 10/09/2015 09:16 pm »
I did a search and could not find a Q&A on Solar Sails so I thought I post this here. I was watching a video on HELIOS advanced solar sail and did some research on it. Has NASA decided to test this in orbit?

#### Jim

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##### Re: Curious about solar sails
« Reply #3 on: 10/10/2015 12:14 pm »
There is no NASA mission testing solar sails at this time

#### ThereIWas3

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##### Re: Curious about solar sails
« Reply #4 on: 10/10/2015 02:03 pm »
The Planetary Society has a solar sail project, currently scheduled to ride one of the early FH launches in 2016.