The Solar and Heliospheric Observatory (SOHO), launched in 1995, stares mostly at . . . yeah. The sun. But when its instruments are trying to image other things near the sun, all that light gets kind of overwhelming. So sometimes instruments on the SOHO just block the sun out and turn their attention to other things. Like this sungrazer comet.
Imaged in 1996, the Christmas Comet SOHO 6 is moving through the corona of the Sun, a sort of cloud of plasma around the star. The image shows the inner 8 million kilometers of the corona, and the gas being released by the comet as it comes closer to the sun and begins melting (comets are icy by definition).
SOHO has imaged over 1,500 comets, including other sungrazers like this one. Most sungrazers, like this one, are thought to come from a single large comet that passed the sun in the 12th century and broke up, creating the Kreutz family. SOHO 6 did not survive its rendezvous with the sun, though the incredibly bright Comet ISON, which is not from the Kreutz family, is expected to pass the Sun and escape later this year. [Astronomy Picture of the Day]