SDO goes NOVA!

The NOVA special Secrets of the Sun ran Wednesday night, highlighting the SDO data and scientists. You can still watch it at WGBH. The SDO Weekly report for April 26, 2012 was pretty short: The FOT supported the lunar transit on 4/22. They also supported the monthly Atmospheric Imaging Assembly (AIA) Guide Telescope (GT) Calibration on 4/26.

Lunar transit and Camilla on TV

Yesterday SDO had another lunar transit. Here is an example of this grazing transit.
Good Morning America will feature Camilla SDO and the crew that sent her into the stratosphere during a solar storm. This has already been reported on discovery.com, huffingtonpost.com, and BBC.co.uk. I liked the movie of the balloon popping.
Check it out! Here is a link to the segment about the balloon launch.

Maneuvers and Images

Last Wednesday and yesterday (April 11 and 18, 2012) we performed several spacecraft maneuvers to help calibrate our instruments. On April 4 we did an EVE cruciform and an AIA bakeout. This means the Sun moves back and forth and up and down. AIA images may be noisy (because the CCDs were warmed up to reduce contamination) and the Sun absent during this maneuver. HMI images may not show the Sun, or show it whizzing by as SDO moves.

On April 18 SDO did an EVE field of view and HMI flatfield maneuver.

While we do these maneuvers the data may be unavailable but by doing these maneuvers we keep the instruments healthy.

SDO 360 degree roll

The Helioseismic and Magnetic Imager (HMI) instrument, one of three instruments on board NASA's Solar Dynamics Observatory (SDO), is making precise measurements of the solar limb to study the shape of the Sun.

Twice a year, the SDO spacecraft performs a 360 degree roll about the spacecraft-sun line. This roll maneuver allows us to remove the instrument optical distortions from the solar images taken by HMI to precisely determine the solar limb.

Thanks to the high resolution observations of the HMI instrument, solar scientist can measure if the Sun's sphere is changing over time as a result of the solar cycle. On April 4, 2012 SDO performed its 6th roll and the accumulated data is being studied and reviewed and will later be published in a paper.

4 April 2012 Roll Video

SDO Weekly Report for March 29, 2012

The FOT performed the SDO Station Keeping maneuver number 4 (SK4) on 3/28. We used 69 grams of propellant to keep SDO within our assigned box.

An HMI roll was performed this morning (April 4) starting at 0550 UTC.

AIA images are again current.

AIA Images are Delayed in Processing

AIA images in several channels are delayed in processing. They should be up-to-date soon.

Last Eclipse of the Spring Season

Today we had the last eclipse of the Spring 2012 Eclipse Season. Here are 4 images of the Sun at about 0630 UT today. Comparing the upper left image (1600) with the upper right and lower left we see the different ways the Earth's atmosphere absorbs light from the Sun. Ultraviolet light at 1600 Å is absorbed about 105 km above the surface of the Earth while 193 is absorbed at 130 km and 304 at 150 km. (171 is absorbed at 120 km). The 1600 edge is pretty straight while the others are rougher. Changes across the disk of the Sun are important in the other three channels, but the effects of changes in the Earth's atmosphere at 150 km can be seen at the top of the 304 image.

To really see the effects of the Earth's atmosphere you should use difference images. If all of the solar patterns can be determined you can map the Earth's thermosphere with these partial occultations.

Next on the schedule is a ΔV burn today at 2315 UTC (7:15 pm ET).