For the first time, a death-diving comet has been observed as it vaporized in the sun’s atmosphere, thanks to new data from a NASA satellite. More than a thousand known comets are so-called Kreutz sungrazers, a family of icy bodies that pass very near to the sun’s surface on their orbits through the solar system. Using NASA’s Solar and Heliospheric Observatory (SOHO), astronomers are able to spot many of these sungrazers as they get close to our star. Now, using a variety of data from NASA’s Solar Dynamics Observatory (SDO), astronomers have been able to watch a sungrazer’s last moments as it disintegrated inside the sun’s atmosphere. According to Karel Schrijver, a fellow at the Lockheed Martin Advanced Technology Center in Palo
Alto, California, the observations should provide valuable information about both comets and the sun. Comet was traveling some 400 miles per second and made it to within 62,000 miles of the sun’s surface before evaporating. Before its final death throes, in the last 20 minutes of its existence when it was visible to SDO, the comet was some 100 million pounds, had broken up into a dozen or so large chunks with sizes between 30 to 150 feet, embedded in a “coma”, that is the fuzzy cloud surrounding the comet, of approximately 800 miles across, and followed by a glowing tail of about 10,000 miles in length. As sun-diving comets disintegrate, they could reveal much about how comets in general are put together and what their components are. Since comets date back to the origins of the solar system, such details about their death throes could lead to a better understanding of how the planets evolved from protoplanetary gas and dust. The behavior of these comets as they graze the sun also could shed light on the sun’s mysterious high-altitude atmosphere. According to scientists understanding how the sun’s atmosphere works could in turn reveal more about the operations of the sun’s roiling surface, which can often burst with solar flares that affect Earth.