Part 3/12:
Getting any object off Earth requires overcoming a formidable barrier known as escape velocity—about 11.2 km/s (roughly 25,000 mph). To put it in perspective, this is nearly 30 times faster than a rifle bullet. Achieving such speeds demands monumental energy and vast amounts of fuel. For example, the Saturn V rocket, which launched Apollo astronauts to the moon, contained over 2 million liters of fuel—liquid oxygen and kerosene—just to push a small capsule into lunar orbit.
The Parker Solar Probe, intended for solar proximity studies, exemplifies the complexity: despite its smaller tanks, it required multiple launches, gravitational assists, and years of precise planning to reach its goal.