Weirdly, spaceships have no direct way to gauge their own speed. Luckily, we can use some physics tricks to figure it out. Here on Earth, it’s easy to know how fast you’re driving. You get a good ...

There is technology being perfected to make particle accelerators 100-1000 times lower cost. This would enable production of nuclear material for space propulsion that could reach up to 0.5% of light ...

When the Sun reaches higher levels of activity, junk drifting in low Earth orbit loses altitude at an increased rate — and for the first time, scientists have measured that increase and identified ...