What can we learn
from a solar eclipse observation? We know that the
corona is very, very hot (over one million
degrees), but we're not sure why. We're interested
in finding out what makes it so hot. We think
waves might carry energy into
the corona, so we've been looking for waves
in the corona, which are visible during a
solar eclipse.
We use a special digital movie camera to study
the corona during
a solar eclipse. The problem is that solar eclipses don't
last very long, so the camera has to work really,
really fast. Our camera takes 50 images every second.
What we are looking for are waves moving through
the corona,
just like waves on the surface of a pond.
Our camera, and the computer system which drives it, is called SECIS (Solar Eclipse Corona Imaging System).
You can observe detailed movement more clearly if you take lots of pictures in rapid succession.
One great thing of course is that we get to go to eclipses in lots of interesting places. We went to Guadeloupe in 1998, to Bulgaria in 1999 and to Zambia in 2001. In Zambia, we set up our equipment on the roof of the University in Lusaka. There were lots of African students and families up there with us. When totality happened, they got so excited that they started to sing and dance, which gave us a few more waves and vibrations than we had hoped for. Doh!
Credit: Habbal et al.
Here is an eclipse image take with different filters in the visible. Red corresponds to plasma around 1 Million degrees and green is around 2 Million degrees.