Asteroids and comets come in all shapes and sizes—from small pebbles, to larger SUV-sized fragments, to massive asteroids like Ceres, which has a diameter of about 621 miles. Much of the asteroid material that crosses paths with the Earth burns up when it enters the atmosphere. About once every 100 years, though, a fairly large asteroid strikes the Earth.
Russia's proposal for an Armageddon-style mission to deflect the space rock Apophis seemed bold, but it's not the only one fretting about a catastrophic impact on Earth. The U.S. National Research Council (NRC) released a new report that calls for an international asteroid defense agency that can organize a proper mission to counter possible asteroid threats, New Scientist reports.
The harvest moon--which came a couple weeks late this year, on Oct. 4--has long allowed farmers to gather their crops late into the night, using moonlight as a beacon.
Someday, the moon might yield a harvest of its own, thanks to a natural supply of water. A NASA probe is set to crash into the moon this week in search of that potential bounty. Here's how you can watch it from here on Earth.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.