Yes, it is easy to penetrate the atmosphere quickly, and burn up like a meteor. The problem is to enter slowly. You can do that too, but it would take a HUGE amount of fuel with ordinary rockets. You can do it with aerobraking, including a surprisingly slow re-entry with an orbital airship; and there are some other ideas that may be possible in the not too distant future, such as a space elevator, or spinning “skyhooks”. To see why it is so difficult with ordinary rockets, here is a quick refresher on orbits. If you could throw a ball from above our atmosphere, gravity still pulls it down in the same way as on Earth, If you throw it fast enough, what happens is that it gets beyond the horizon before it can hit the Earth, and Earth’s gravity continues to pull it around into a curve until it gets back to its starting point. That’s how satellites such as the ISS stay in orbit, and that’s why it is often called free-fall. To skim the Earth’s atmosphere in orbit, your spacecraft has to