4 ms·
To move towards the sun when orbiting it, you don't need to accelerate towards the sun, you need to accelerate towards your retrograde vector.
by Tuna-Fish 11y ago
To move towards the sun when orbiting it, you don't need to accelerate towards the sun, you need to accelerate towards your retrograde vector.
- TeMPOraL 11y agoIndeed. To explain the technical term, retrograde is the reverse of where you're going (where your velocity vector is pointing). Accelerating retrograde (against the direction of your movement) = dropping your current orbital velocity = when you "slingshot" to the other side, you'll be closer to the Sun. Orbital mechanics is fun :).
- knodi123 11y agothat's a good point, I forgot orbital mechanics. However, what's the ratio of the acceleration due to light pressure vs. due to gravity? If you are at rest 1 au from the sun, and you deploy your sail perpendicular to sunlight, which direction will you accelerate in?
- JoeAltmaier 11y agoDoes a prism get affected by the momentum of the light it bends? Can you use a prism to bend the light to any angle you need to drive your sail?
- Tuna-Fish 11y agoTowards the sun, by a very large margin. Of course, no spacecraft will ever be at rest with regards to the Sun -- it would take 30km/s of delta-v to get there, and there's rather little point. They will be orbiting, starting from leo, which means that the meagre acceleration from a sail is more than enough to get basically anywhere.