Asteroid impacts on Earth are more common than we think, and the B612 Foundation believes that its proposed $250 million Sentinel telescope could help detect when one might strike.
The group — which includes several former NASA astronauts — says that the Sentinel would be able to track 90 percent of Earth-orbit-crossing asteroids larger than 100 meters, and would give years or even decades of notice before one of them potentially hits the Earth.
From 2000 to 2013, a network of sensors operated by the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) picked up 26 major explosions on Earth, all of them caused by asteroids making contact or bursting apart in the atmosphere. They ranged in energy from 1 kiloton to 600 kilotons (the bomb that destroyed Hiroshima was 15 kilotons) — and just one was picked up hours in advance. That's why the B612 Foundation wants Earth to have a fighting chance when it comes to predicting asteroid strikes.
"In the cities that have a major danger — Tokyo, Los Angeles, San Francisco — they know the odds of big earthquakes by observing how many small earthquakes there are," B612 Foundation CEO Ed Lu, a former astronaut, tells BBC News. "And you can do this with asteroids.... These asteroid impacts in the last decade have been ones that we haven't had much data on until recently, and they tell us that in fact asteroid impacts are more common than we thought." To find out more about the Sentinel project, watch a video of various asteroid impacts below. --Catherine Garcia