Important notice about STEREO Behind
CME across space
Several instruments on STEREO (Behind) observed the progress of a good-sized coronal mass ejection (CME) as it blasted out from the sun and into space (Jan. 21-25, 2009). The burst of particles was first spotted late on Jan. 21 by the COR2 coronagraph as a bulbous cloud with a bright core, which expanded to the right. With its broad field of view to the right of the sun the HI1 instrument picked up the cloud early on Jan. 22 and watched it expand even further over the next two days. (The very bright object to the right of the middle is Venus.) Lastly, the HI2 imager (see video) tracked the much fainter CME cloud as it crossed millions of miles of space and continued to expand further through Jan. 25. The CME did not appear to generate any effects here on Earth, but the CME was detected by the other STEREO spacecraft (Ahead) as it passed by. With their suites of instruments the STEREO spacecraft are providing us with new views of how CMEs evolve over time.
Last Revised: March 19, 2018 15:00:39 UTC
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