3 ms·
It's just barely feasible with fusion energy densities. To accelerate a million tons to 0.1c you need as much kinetic energy as is theoretically contained in a
by mateo1 4y ago
It's just barely feasible with fusion energy densities. To accelerate a million tons to 0.1c you need as much kinetic energy as is theoretically contained in a million tons of hydrogen you'll fuse. Maybe with antimatter, but traveling so fast causes a ton of other issues, like every single particle you encounter is also traveling at ~0.1c.
- deleted 4y ago[deleted]
- titanomachy 4y agoThis checks out! Kinetic energy = 0.5 mv^2, where v = 0.1c => E = 0.005mc^2 (relativistic effects not too important at this speed). Fusing a kilo of hydrogen converts ~6g to energy; at E = mc^2, that's 0.006mc^2. So the energy needed to accelerate a given mass of hydrogen to 0.1c is almost exactly equal to the energy produced by fusing that hydrogen.
- hinkley 4y agoI believe the math works out such that any slag you create while refining construction or fuel materials needs to be launched out the back of the ship as fast as you can (frequency and velocity) so that you're not accelerating it along with the rest of the rock. Though probably not exactly straight out the back, since that would create a navigation hazard for the next ship...