There are roughly 40,000 pieces of debris larger than a softball in Earth orbit, about 1.1 million between a marble and a softball, and an estimated 130 million smaller than a millimetre. All of it is travelling at around 17,000 mph. So what is space debris in practical terms? It is the reason the International … Read more
The hardest part of explaining how do mars rovers work is that the rover itself is the easy half. Designing a car that can drive around Mars is a solved problem. Getting it onto the surface intact — through an atmosphere too thin to brake with parachutes alone and too thick to ignore — is … Read more
Most explanations of how do satellites work start with gravity and stop there, which leaves the interesting parts out. A satellite is not a machine that floats; it is a machine that is permanently falling and permanently missing the ground. Get that one idea straight and the engineering — the orbits, the power budget, the … Read more