WMAP moves into solar orbit

WMAP was sent into independent solar orbit on Wednesday Sep. 8 2010 at 11:20 am EDT. Throughout its 9 year mission, the observatory orbited at the outer Lagrange point (L2) of the Sun-earth system. Because this point is unique & is used by other observatories, NASA wanted WMAP to vacate this orbit.

The re-orbiting maneuver required a 20 minute burn producing a delta-v of 6.69 m/s. If no further burns are done, WMAP will have entered a superior heliocentric orbit roughly 7 million km above the Earth's orbit (recall that L2 is 1.5 million km above). In this configuration, the Earth will lap WMAP roughly every 14 years.