Aside from, can eyes in the sky help save us from asteroid hits?
Canada thinks so, and it has launched a space telescope to track hazardous objects including asteroids, space junk, and satellites.
The Near-Earth Object Surveillance Satellite (NEOSSat) was launched from an Indian rocket this week as the first dedicated space-based sentinel of its kind.
Managed by the Canadian Space Agency (CSA) and Defence Research and Development Canada (DRDC), NEOSSat is about the size of a suitcase and orbits some 500 miles above Earth, circling every 100 minutes.
Unlike ground-based telescopes, it can operate 24/7 and won't be limited by the day-night cycle. It will generate hundreds of images per day for analysis by researchers on a team including Alan Hildebrand at the University of Calgary.
"There are currently no space telescopes that are dedicated to survey the sky to discover near-Earth asteroids (NEAs)," CSA Senior Program Scientist Denis Laurin told Crave.
"In order to find as many as possible NEAs, a systematic or strategic survey and search procedures must be followed occupying all of the observation time of the telescope. Although many space telescopes could image asteroids in general, they have other mission goals (e.g. space astronomy)."
Based on Canada's Microvariability and Oscillations of Stars (MOST) satellite, NEOSSat has a highly stable attitude control system that allows it to point its 5.9-inch aperture f/5.88 Maksutov telescope at the same area of space for up to 100 seconds.
While its baffle design lets it gather data within 45 degrees of the sun, NEOSSat would not have been able to detect the meteor that hit Russia earlier this month as it came out the star's direction.
"NEOSSat's observations will probably reduce the impact hazard from unknown large NEOs by a few percent over its lifetime," the project's Web site says, "but it isn't designed to discover small asteroids near the Earth that may be on collision courses."
With potentially millions of undiscovered NEOs out there, at least it's doing something.