Eyes in Space - Canada's sentinel in the sky

Canada's NEOSSat

The surprise explosion of a meteor over Russia on 15th February this year, again served as a reminder of the vulnerability of the planet and its' inhabitants to contact with near-earth objects. The meteor was undetected and estimated to be approx 17 metres wide delivering a 470-kiloton blast with a shock wave that damaged 3,000 buildings and injured over 1,500 people in the Chelyabinsk region of Russia.

Canada has added to the relatively small number of assets available for space monitoring with the launch on 25 February 2013 of the Near-Earth Object Surveillance Satellite (NEOSSat). The suitcase-sized NEOSSat orbits approximately 800 kilometres above the Earth, searching for near-Earth asteroids that are difficult to see using ground-based optical telescopes. NEOSSat is not limited by the day-night cycle but operates round the clock. It circles the globe every 100 minutes, scanning space near the Sun to pinpoint asteroids that have proximity to the Earth. Despite the additional surveillance there remains a significant number of unseen objects as shown below. 

Size in metres	Unknown %
1,000 upwards	7%
150-999	67%
40-149	99%