How fast do you need to go to leave each world forever?
Escape velocity is the minimum speed you need to break free of a planet's gravity, without any additional propulsion. If you're going slower, you'll fall back. If you're going exactly escape velocity, you'll keep drifting away forever, slowing down but never stopping. If you're going faster, you'll outrun gravity entirely.
The formula is simple: v = √(2GM/r). G is the gravitational constant, M is the mass of the body, and r is its radius. More mass = higher escape velocity. Smaller radius = higher escape velocity. A neutron star packs the Sun's mass into a city-sized ball — its escape velocity is half the speed of light.
On Earth, escape velocity is 11.2 km/s (40,270 km/h). That's why rockets are so expensive — you need to burn a massive amount of fuel to reach that speed. The Saturn V rocket that went to Apollo was the height of a 36-story building, and 90% of it was fuel.
11.2 km/s, or about 40,270 km/h. That's 33 times faster than a rifle bullet. The Saturn V rocket reached about 11 km/s to get to the Moon.
Yes — but it needs a lot of fuel. To reach 11.2 km/s, a rocket needs to carry about 90% fuel by weight. That's why rockets are so huge. The fastest human-made object is the Parker Solar Probe, which reached 692,000 km/s (192 km/s) using gravity assists.
At the event horizon, escape velocity equals the speed of light. That's why nothing can escape — not even light. Inside the event horizon, escape velocity exceeds light speed, which is impossible.
No. The Moon's escape velocity is 2.4 km/s. A human jump reaches about 2 m/s. You'd need to be moving 1,200 times faster than a running start to leave the Moon under your own power.