Thursday, January 20, 2022

The Winter 2022 EVE Cruciform is Complete

Yesterday SDO performed an EVE Cruciform maneuver starting at 1400 UTC (9:00 am ET). During this maneuver the SDO spacecraft nods back and forth and up and down. The science images appear to move as well and can be blurry.

Over the next few days SDO will be supporting the validation of the PHI instrument on Solar Orbiter. PHI is similar to the HMI instrument on SDO. It uses the same spectral line of iron at 6173 Å to measure the line-of-sight Doppler velocity and the vector magnetic field on the solar surface. This weekend marks a time when the SO orbital position allows the scientists to do stereoscopic helioseismic observations, a first for us.

Next month, on 25 Feb 2022, SDO will support the 11th perihelion passage of the Parker Solar Probe.

Other dates of interest are: The Spring 2022 Eclipse Season starts 24 Jan 2022 and ends 17 Feb 2022. Stationkeeping Maneuver #24 is tentatively scheduled for 2326 UTC (6:26 pm ET), 02 Feb 2022.

Tuesday, December 21, 2021

Celebrate the Winter Solstice at 11:59 am ET today!

Today is the Winter Solstice. The length of daylight is the shortest of the year in the Northen hemisphere and the longest in the Southern. For the Northern hemisphere it corresponds to the beginning of the cold winter season while people in the Southern hemisphere are starting to enjoy their summer time weather.
The occurrence and timing of solstices was known to many early cultures, from Mesopotamia to Mesoamerica. It was a time to celebrate when the Sun stopped moving southward and began moving back to bring warm to their homes. We know that the tilt of the Earth's rotation axis causes the seasons but we continue to celebrate their changes.

Enjoy the Winter Solstice!

Momentum Management Maneuver #42, December 15

SDO executed momentum management (MM) maneuver #42 on December 15 from 1945-2015 UTC (2:45-3:15 pm ET). During an MM maneuver SDO science data may be missing or blurred. These maneuvers are needed to keep SDO accurately pointed at the Sun and taking data.

Thursday, October 28, 2021

X-class flare at 1555 UTC (11:55 am ET)

Active region 12887 emitted an X-class flare today at 1555 UTC. There also appears to be a filament eruption (the precursor to a coronal mass ejection). This is the second X-class flare of Solar Cycle 25 (the first was on July 3, 2021.)

The flare continues to brighten until its peak flux. Check out the flare in the Browse AIA/HMI Images at the SDO website.
Solar Cycle 25 is alive and well!

Wednesday, October 27, 2021

October 2021 Instrument Calibration Maneuvers have Finished

The October 2021 Instrument Calibration maneuvers have finished. During an instrument calibration maneuver SDO science data may be missing, blurry, or misaligned. The first two cannot be corrected but roll angle is no longer seen as a rotation of the solar image.
  • 13 Oct 2021: EVE Cruciform, 1400–1852 UTC (10:00 am - 2:52 pm ET)
  • 20 Oct 2021: HMI Roll Maneuver, 1400-2040 UTC (10:00 am - 4:40 pm ET)
  • 27 Oct 2021: EVE FOV and HMI/AIA Flatfield Calibrations (EVE FOV @ 1315 UTC; HMI/AIA Flatfield @ 1630 UTC)
The next set of calibration maneuvers will be in January 2022 (EVE Cruciform, EVE FOV, and HMI/AIA Flatfield) and April 2022 (HMI Roll).

Wednesday, September 22, 2021

Momentum Management Maneuver #41 today

SDO will execute momentum management (MM) maneuver #41 today from 1820-1840 UTC (2:20-2:40 pm ET). During an MM maneuver SDO science data may be missing or blurred. These maneuvers are needed to keep SDO accurately pointed at the Sun and taking data.

Friday, September 10, 2021

Congratulations to the EVE Team!

NASA 36.353 sounding rocket flight to calibrate SDO EVE and several other satellite instruments was a great success. Hre's the proof, exposures from both the MEGS-A and MEGS-B CCDs in the calibration EVE. The top image is from the MEGS-A CCD with MEGS-A1 spectrum on top and MEGS-A2 spectrum and MEGS-SAM X-ray image on the bottom. The bottom CCD image is the MEGS-B spectrum that goes diagonally across the CCD. The bright (yellow and red) vertical stripes are the spectral lines of the Sun that EVE studies. Just seeing these spectral lines means our Sun has a magnetic field. Without the magnetic field this part of the spectrum would be empty.

I can't wait to see the movie.

Congratulations to the EVE for a successful flight!