Hydrogen is the first element in the periodic table and essential for life on Earth. It may also be key to shifting away from fossil fuels toward clean sources of energy, but challenges remain.
Feb. 28 marks the 75th anniversary of Operation Gunnerside. A stealthy group of skiing commandos took out a crucial Nazi facility and stopped Hitler from getting the atomic bomb.
Some atomic ratio detective work on our solar system neighbors tells us a lot about their watery pasts. That Venus and Mars are mostly dry now could be a cautionary tale for us on the Blue Planet.