Tuesday, September 3, 2013

Fall 2013 Eclipse Season has begun

The SDO Fall 2013 Eclipse Season has begin. Every day until September 25, 2013 some part of the Earth's shadow will pass through the SDO telescopes. Here are pictures from the first eclipse of the 2013 season. On the top is a He II 304 image from 0659 on September 2 and on the bottom is a AIA 193 image from about a minute later. The Earth's shadow appears more ragged in the 193 image because of the way the gases in that atmosphere absorb the EUV light AIA is observing and the way that light is generated by the Sun. The He II plasma tends to be cooler and be held closer to the Sun's surface while the 193 emitting plasma is hot enough to extend well off the surface. You can see that difference by looking at the glow just off the edge (or limb) of the Sun near the top of the Sun.
You use the SDO data browser to flip through these images and see the interplay between the atmospheres of the Sun and Earth.