04.21.10 - NASA's recently launched Solar Dynamics Observatory is returning images that confirm its unprecedented capability to help scientists better understand our sun.
04.21.10 - NASA's recently launched Solar Dynamics Observatory, or SDO, is returning early images that confirm an unprecedented new capability for scientists to better understand our sun's dynamic processes.
04.19.10 - Over the weekend SDO completed the HMI roll maneuvers and began preparing for the image quality jitter tests. The next major activity is to isolate the main engine. First, the isolation pyros on the main engine will be fired to isolate the Helium pressurant and main engine from the observatory. After that is the first 2 Nms delta-H thruster maneuver, used to dissipate momentum.
04.16.10 - The EVE cruciform maneuver was completed yesterday. Other tests included the high-gain antenna handover with stagger stepping and no-step requests. These tests are required to keep the observatory from moving too much while taking an image with HMI and possibly AIA. Next Tuesday we plan to have an Delta-H thruster burn. These momentum unloads are required to keep the reaction wheels spinning at the correct speeds. More...
04.14.10 - NASA will hold a news briefing and unveil initial images from the Solar Dynamic Observatory, or SDO, at 2:15 p.m. EDT on Wednesday, April 21, in the atrium of the Newseum.
04.14.10 - Today SDO ran the EVE Field of View and HMI/AIA Flat Field calibration maneuvers. HMI tested the re-transmission capability of the DDS by asking for re-transmissions of files that were not successfully transferred.
04.13.10 - SDO continued instrument calibration for the past few days. These included an EVE cruciform and guide telescope monthly calibration. During the cruciform scan SDO left inertial mode (an attitude-control mode) and went into sun-acquisition mode. This was traced to a wrong number in a filter that slowly pushed the spacecraft in the wrong direction until an automated response caused SDO to enter sun-acquisition mode. The number was fixed and the GT calibration was run. More...
04.09.10 - Our initial Science Reference Boresight was defined Friday. This is the target for the fine-guidance system in science mode, or it is the imaginary line that leaves SDO and hits the center of the Sun. All of the instruments can then figure out where they are pointed with very high accuracy. SDO completed several calibration maneuvers this week, with more coming in next 10 days. Last nite the HMI/AIA roll was done. More...
04.08.10 - PI Tom Woods and crew arrived in White Sands Missile Range, NM to integrate the EVE calibration rocket on Monday and perform initial checkouts of the payload to make sure it survived. All is going well, and the launch has been moved up to May 3. Upcoming tasks next week are the environmental tests - vibe, spin balance, and bend test. Hopefully we can get ITAR and security approval for pictures quickly and post those here in the near future.
04.06.10 - Last evening the EVE cruciform was completed and the high-gain antenna raster resumed. A cruciform scan is a slow scan in a line through the Sun from East to West and another north to South, about 2.5 degrees in each direction. This is used to map out the field of view of the instrument. The high-gain antennas move quite a bit over a year and the raster scans are used to calibrate the pointing of the antennas.
04.05.10 - Sunday was a day to reflect on all of the data we have collected so far on the interaction of the instruments and the spacecraft. This week we begin a series of instrument calibration maneuvers and more testing of the high-gain antennas. First up is the EVE cruciform maneuver.
04.03.10 - Today the instruments examined how they affect the pointing of SDO. Filters and shutters inside the instruments have to rotate into new positions before each exposure, so SDO has a lot things spinning around. Each instrument ran their filters wheels and shutters to see how SDO moved. After that they tested the guide telescopes that are part of AIA. The "Science Reference Boresight" is determined by these guide telescopes, so understanding their behavior is crucial to SDO.
04.02.10 - SDO spent another day measuring the jitter of the spacecraft, this time how the motion of the two high-gain antennas affected the pointing of the instruments. The instrument teams helped with these tests while continuing to understand their own observing sequences.
04.01.10 - Today SDO worked to understand how the reaction wheels that provide our fine pointing control interact with the spacecraft. SDO needs to point at the Sun very accurately while taking an image every 0.75 seconds (which means rotating shutters and filters), rotating the high-gain antennas to keep them pointed toward New Mexico, and rotate the entire observatory once per orbit to keep it pointed at the Sun. More...
03.31.10 - The doors are open and the CCDs are cold, what's next? For the next several weeks SDO scientists and engineers will work to check out and calibrate the instruments and to coordinate the spacecraft and instruments. I may call it "Focus and Center" but it is a busy time for everyone on SDO making sure these complex instruments do what is needed to get our data. In mid-April we plan to show the world how great the instruments are working at a "First Light Media Telecon."