Comment Re:Cpt Obvious Observation (Score 4, Informative) 154
That comes from the WISE mission: http://wise.ssl.berkeley.edu/mission.html
WISE is a whole sky infrared survey that happens to pick up asteroids. The spacecraft spins to survey a complete arc of sky roughly perpendicular to the Sun direction.
You'll also notice that during much of the 2000s, there is a gap in discoveries at about the 5 o'clock position. This corresponds to monsoon season in the southwest U.S. (roughly July to mid September). Most of the discovered asteroids in the past decade were made by the Catalina Sky Survey, based just outside of Tucson, AZ, and they generally don't bother observing during monsoon season because of the increase in cloud cover.
You'll also notice that during much of the 2000s, there is a gap in discoveries at about the 5 o'clock position. This corresponds to monsoon season in the southwest U.S. (roughly July to mid September). Most of the discovered asteroids in the past decade were made by the Catalina Sky Survey, based just outside of Tucson, AZ, and they generally don't bother observing during monsoon season because of the increase in cloud cover.