Farewell Comet ISON

The STEREO Ahead spacecraft was in a great position to observe Comet ISON as it raced to its closest passage by the Sun (Nov. 28 - 29, 2013). It featured a brilliantly elongated tail as it passed the coronagraph’s occulting disk (within 1 million km). Then, it apparently broke up into smaller pieces that continued on its orbit path, much reduced in brightness and with little tail. Hopes that it would become a very bright comet were dashed. the comet is still visible in Ahead HI1, and we will continue to observe it as long as we can. (Lower left bright object is Mercury.) Credit: STEREO/NASA.

• ISON_COR2_best.mov   
• ISON_COR2_sm.mov   
• ISON_COR2_vs.mpg   
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