Browse Archive

  • SDO Day 48: AIA Gets Cool

    03.30.10 - All of the instruments are now working with doors open and cold CCDs. Around 20:00 UT Monday the AIA CCD heaters were turned off, upon which the CCD temperatures dropped rapidly from about +40C to -70C then slowly settled towards their final temperatures. With that drop in temperature, we saw the camera background decrease markedly, and the image quality in all channels improve dramatically.  More...

  • SDO Day 47: A Weekend of Work

    03.29.10 - SInce opening all nine doors, work has continued getting the instruments ready for normal science operations. HMI continues to work on sequences and the image stabilization system. EVE is working on understanding their data. AIA is looking at solar images superimposed on the thermal background of their still-warm CCDs and updated their on-board flight software.

  • SDO Day 45: AIA Doors are Opened

    03.27.10 - The AIA team members at the MOC celebrate the successful opening of all four AIA telescope doors by 15:30 UTC (11:30 am ET) on Saturday. The doors were opened in the order (by telescope number): 1, 4, 3, and 2. The AIA CCDs are still warm. On Monday the decontamination heaters will be turned off, and the sequencer will be started so the CCD cool-down can be observed. All nine SDO instrument doors are now open.

  • SDO Day 45: EVE Doors Open and the Sun Celebrates

    03.27.10 - Almost immediately after the EVE doors opened active region 11057 provided some fireworks and let loose with 4 C-class flares! Here is a graph from the NOAA SWPC in Boulder, CO showing the GOES X-ray fluxes. The EVE doors were all opened by 19:43 UTC, and the flares started at 21:08 UTC. EVE will study the energetics of such flares while HMI and AIA tell us how and why they form. Welcome to Solar Cycle 24.

  • SDO Date 44: EVE Door Opened

    03.26.10 - At 3:43 pm ET all four EVE doors were open. HMI and AIA were able to measure the jolt of the doors. AIA doors are to be opened tomorrow.

  • SDO Date 44: Spacecraft Jitter Tests

    03.26.10 - Thursday was spent testing the "jitter" of the observatory. Why do we care? SDO needs to keep its imaging telescopes pointed at the Sun with a steady hand. Our pixels image an area of the Sun that is about 0.5" across. While that's a patch the size of New Mexico on the Sun, it easier to think of it in terms of a quarter.

  • SDO Day 42: HMI Opens Door, West Coast Style

    03.25.10 - During the HMI door opening a large part of the HMI team was at Stanford. They celebrated the successful door opening and our first chance to see what the HMI instrument will do for solar studies.

  • SDO Day 42: HMI Opens Door

    03.24.10 - At 11:00 am EST this morning HMI began opening their door. This door protected the front window and optics from damage but can now be opened to let the Sun shine in. Sunlight was used to illuminate the front window and study the optical performance of the telescope. A sunspot could be seen in these engineering images.

  • SDO Day 42: The Doors Begin To Open

    03.24.10 - This morning the HMI door will be opened. Engineering images to test HMI will begin to flow. These will start with pictures of the door opening that allow the HMI team to study scattered light inside the instrument.

  • HMI CCDs Are Cold, EVE CCDs Are Cooling

    03.23.10 - The instrument teams of SDO began their work to start taking data. HMI allowed its CCDs to cool over the weekend and EVE started the cooldown cycle on Tuesday. AIA plans to watch the Sun while their CCDs cool to operational temperatures later this week. The Ka-band transmitter was turned on and high-rate (150 Mbps) data is flowing to the SOCs.

  • A Busy Day for the Instruments

    03.20.10 - Friday was a day to run in science mode. SDO ran all three instruments over night with test patterns. The EVE instrument completed its component check outs.

  • From Tom Woods, EVE PI

    03.19.10 - Great news for EVE: all of the EVE subsystems are now turned on and all are doing very well !!! We turned on ESP, MEGS-A CCD, and MEGS-B CCD for this first time this morning. Their dark data look fine. Every component looks healthy.

  • Ka-band Up And Running

    03.18.10 - Wednesday was a very good day for the SDO observatory and team. The Ka-band transmitter was turned on, the antennas pointed at the ground station, and data started to flow. Both ground antennas locked immediately and had good signal strength. HMI and AIA generated test pattern data, which was transmitted to the ground and forwarded to the JSOC without any errors.

  • SDO Is On Station

    03.16.10 - The third Trim Motor Firing (TMF #3) was successfully completed Tuesday evening. This apogee burn raised our perigee to geosynchronous with an orbital period of one day. SDO is on station, next is to start up the instruments!

  • Tracking SDO's Attitude With the Stars

    03.16.10 - How does SDO know where it is pointing? Seems easy, just point at the brightest object in the sky! But what about our roll angle around the Sun, or where is the Sun's North Pole? SDO uses star trackers to measure its attitude. CCD images are compared to a library to see where the star tracker is pointed. Once we know where the star trackers point we can figure out our roll angle on the Sun.