Space mining is an idea that began taking hold at the turn of the century, and 10 years ago, it was passionately discussed. Many argued that space mining could revolutionise the commercial space economy by employing robots and private astronauts to explore and mine near-Earth asteroids (NEAs) for precious metals and even rare earth metals.

A U.S. military space plane is being used to flight-validate the best ways to gather the sun's energy for power beaming from Earth orbit. In mid-March, the latest classified mission of the U.S. Space Force's X-37B robotic space plane winged past 300 days in Earth orbit.

airspacemag.com A spacewalk in Earth orbit-any spacewalk-requires working in a deadly vacuum for six hours in a stiff spacesuit. It's an exhausting physical and mental challenge, and that's if everything goes well.

The U.S. military thought it had cleared the decks when, on 9 July 1962, it heaved a 1.4-megaton nuclear bomb some 400 kilometers into space: Orbiting satellites were safely out of range of the blast. But in the months that followed the test, called Starfish Prime, satellites began to wink out one by one, including the world's first communications satellite, Telstar.