Friday, May 1, 2015

Happy 5th Birthday to SDO Science Data!

Today is the 5th birthday of SDO Science Data. On May 1, 2010, SDO was commissioned as a NASA observatory and began sending science data to scientists and the public. We have watched Solar Cycle 24 rise to solar maximum, storing about 7 PBytes of data, releasing almost 200 million images, and having about 1900 scientific papers published describing new things we have learned.
I thought I would share two new images that show the solar magnetic field as only SDO can. The first is the average of the HMI magnetic field at each point on the Sun. White areas show where the magnetic field points out of the Sun and black regions are where the field points into the Sun. Grey regions have a magnetic field of zero. The Carrington longitude is used to give features on the Sun a position. We use the sine(latitude) rather than the latitude to avoid having the Sun look distorted like the Mercator maps of the Earth. The little circles are individual active regions. Even though this is an average over the last 5 years, we can see diagonal swaths of field in both the north and south hemispheres.
The other picture is how much each point on the Sun changed over those five years. The white points changed a lot while the black points changed very little. Now you see the diagonal lines a little better. Most of the changes in the solar magnetic field happen in the "active latitudes" where sunspots and flares are found. Very little happens at high latitudes. There is also very little happening along the Sun's equator.
You should compare these pictures with the averages of AIA 171 released two years ago.

SDO was launched to study the Sun's magnetic field. It is done a great job of recording the magnetic field, flares, filaments, and coronal holes during the rise of Solar Cycle 24. As Solar Cycle 24 fades SDO will continue to measure and report the magnetic field and what that magnetic field does in the solar atmosphere.

Thanks to the HMI for creating the maps of the magnetic field I used to create these pictures, and many thanks to the entire SDO team for the amazing mission they have run for the last 5 years.

SDO is GO!