Caption: This image shows the large, diffuse cloud of CN gas around the nucleus of Hartley 2. It was obtained on October 27th, when the spacecraft was approximately 9 million kilometers away. The image has been processed to remove most of the stars and to bring out the faint coma (logarithmic stretch). The image measures approximately 20,000 km on the side. Because the comet's gravity is very small, gases in the coma can escape freely until they are destroyed by UV light from the Sun. At the comet's distance from the Sun, the CN gas forms a cloud of more than 200,000 km in radius - 10 times larger than the spacecraft's MRI field of view.
|Spacecraft:||Deep Impact Flyby|
|Instrument:||Medium Resolution Instrument (MRI)|
|Mid-exposure Date/Time (UTC):||2010/10/27 06:58|
|Pointing:||RA 20h 42' 31"
Dec +37° 13' 24"
|Field of View:||approximately 23,000 km at the comet|
|Solar Phase Angle:||79°|
|Sun-Comet distance (r):||1.0588 AU (158 million km)|
|DIF-Comet distance:||0.0588 AU (8.8 million km)|
Table 1: Data about image.