This visitor from deep space, seen here by NASA's Wide-field Infrared Survey Explorer, or WISE, is comet Hartley 2 -- the destination for NASA's EPOXI mission.
The comet, known officially as 103P/Hartley was discovered recently, in 1986, by Malcolm Hartley in Siding Spring, Australia. It probably originated from an icy orbit close to that of Jupiter's, before something knocked it on a path toward the sun. The comet circles the sun every 6.46 years -- its upcoming closest approach to the sun, called perihelion, will take place on Oct. 28, 2011. EPOXI, which utilizes the already "in flight" Deep Impact flyby spacecraft, will reach the comet on Nov. 4.
The fuzzy background in this picture is noise, primarily from dust in our own solar system. Stars cannot be seen because they are subtracted out during the process of averaging multiple WISE pictures together into this one view.
Infrared light of 4.6, 12 and 22 microns is colored blue, green and red, respectively.