Asteroid Hunter the First Private Deep-Space MissionThe B612 Foundation announced a few days ago a new, private space telescope called the Sentinel. Its sole purpose will be to hunt out asteroids that could pose a threat to our continued existence, of which most have yet to be discovered. This mission will be a landmark not only in that we will finally be combing the skies regularly for danger, but that tis will be the first privately funded deep-space mission.
The telescope will be a half-meter telescope similar in design to the Spitzer and Kepler telescopes already in operation, though it will be a bit smaller. Construction will begin this fall.
It will hunt the heavens for asteroids larger than thirty meters in size that will intersect with the Earth within the next 100 years.
If you remember, a kilometer-wide asteroid flew quite close to the Earth last month. It did so just four days after its discovery, which would have been far too little time to intercede in any way. The further out we catch the rock, the better our chances are of averting disaster.
Until now, there have been no concerted efforts to detect large incoming asteroids. NASA's Wide-field Infrared Survey Explorer (WISE for short) added 33,500 objects to our astral catalog, but it was retired in 2011 due to a lack of funding. It also wasn't meant to hunt for asteroids but instead Y-dwarfs, which are nearly invisible brown dwarf stars.
While the fact that the human race is still alive would seem to indicate that there haven't been too many large asteroid impacts, much of our history is not well documented. We do have a record of one impact with what was at most a 100 meter rock, though, from 1908. It has become known as the Tunguska event.
The Tunguska event resulted in an air burst of the incoming rock that was the equivalent of between a 10-15 megaton explosion, making it rougly 1,000 times more powerful than the one dropped on Hiroshima. It flattened 2,150 square kilometers of trees. If that had hit a populated area (of which there are far more than at any other point in history) then million or more would have died. And estimates put the number of rocks larger than that one in the inner solar system at around 500,000.
If you want a more detailed analysis of the mission, go check Ars Technica's coverage here. As always, they are detailed nearly to a fault.