First, some background. Comet C/2011 N3 (SOHO) belongs to a group of comets known as the Kreutz family. The Kreutz family is notorious for cruising perilously close to the sun's surface. In the last ten years, solar monitoring observatories have detected over 1,600 members of the Kreutz family playing chicken with the Sun's corona; but for all those daredevil comets, not a one had been tracked making an entrance into its roiling, plasma-laden atmosphere. Consequently, nobody had ever seen what happens to a Kreutz comet in its final moments.
When it made its death dive, researchers at NASA's Solar Dynamics Observatory (SDO) were able to capture a 20-minute movie of Icarus' transit, a time lapse of which is shown here (the coronal mass ejection that you see shortly after the comet passes in front of the sun, while awesome-looking, is entirely coincidental). With the comet traveling at speeds exceeding 600 kilometers per second, those 20 minutes were enough to capture the comet's approach, its complete obliteration in the Sun's lower corona, and everything in-between.
The SDO's Atmospheric Imaging Assembly (AIA) instrument captured the first ever video of a comet passing directly in front of the sun in the early morning of July 6, 2011. The comet comes in from the right and is very faint.
On the evening of Tuesday, July 5, a comet flew into the sun. Such comets are not unusual, and they're called "sungrazers" since they come so close to the star that it is believed they evaporate and disappear. However, no one has actually seen the end of that journey, since the comets are best seen in cameras from SOHO (SOlar and Heliospheric Observatory) that block out the bright disk of the sun itself.
At its most basic, the movie has scientists excited since it's a "first," but additional analysis of the data may hold more clues about the fate of the comet. Most likely, given the intense heat and radiation, the comet simply evaporated away completely.
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