18 Jun 2023 Lunar Transit

Between 0557--0612 UTC (01:57--02:12 ET) on 18 Jun 2023, SDO is experience a brief lunar transit. The Moon will cover about 3% of the Sun, but because it will pass over the top diode SDO will leave science mode during the transit.

Here is the Flight Ops Team movie of the transit

I hope everyone is enjoying SDO's view of the Sun as we near the maximum of Solar Cycle 25!

20 May 2023 Lunar Transit and the Long-term Predicts for the 3rd Quarter of 2023

The 2023-094 FDS Quarterly (Long-Set) Predicts have been delivered. They include events through 05 Nov 2023. The highlights are:

• 20 May 2023, 0222--0306 UTC (22:22--23:06 ET) - LunTran_2023140_3dc_82pshdw
• 18 Jun 2023, 0557--0612 UTC (01:57--02:12 ET) - LunTran_2023169_1dc_3pshdw
• 21 Jun 2023, TBD - Tentative date for Momentum Management Maneuver #47
• 04 Jul 2023, 1148 UTC (07:48 ET) - Handover Season Starts with First Handover (-Z HGA Active Prior)
• 20 Jul 2023, 0725 UTC (03:25 ET) - Eclipse Season Starts
• 26 Jul 2023, TBD - Tentative Date for Station Keeping Maneuver #27
• 04 Aug 2023, 1913--1919 UTC (15:13--1519 ET) - Solar RFI
• 05 Aug 2023, 1910--1918 UTC (15:10--1518 ET) - Solar RFI
• 06 Aug 2023, 1909--1916 UTC (15:09--15:19 ET) - Solar RFI
• 15 Aug 2023, 0248 UTC (22:48 ET) - Handover Season Ends with Completion of Last Handover (+Z HGA Active After)
• 16 Aug 2023, 0659 UTC (02:59 ET) - Eclipse Season Ends
• 05 Nov 2023, 0200 ET - Daylight Saving Time Ends, GSFC Local Time now UTC-5:00

(All dates and times in parentheses are GSFC Local time.)

Here is a movie of the predicted 20 May 2023 lunar transit:

And here is what a daily movie shows for that date:

EVE Calibration Rocket, May 3, 2023, Streaming on NASA TV

All is Go for the launch of the SDO EVE calibration rocket (NASA #36.389) on May 3. The EVE Team has approvals from NASA, WSMR (White Sands Missile Range, where the flight will occur), and the Navy (who run the launch pad) for a launch window of 18:10-18:40 UTC (2:30 PM - 2:40 PM ET). The weather forecast for White Sands, NM, is also looking good.

The EVE sounding rocket used to calibrate the SDO EVE instrument launches from the White Sands Missile Range in New Mexico in 2015. (Image courtesy LASP.)

NASA TV will stream the launch starting at 11:45 AM MDT (1:45 pm ET) at the link https://video.ibm.com/channel/nasa-tv-wallops.

Enjoy!

Calibration Activities Today 1700-2030 UTC

The SDO Team will power cycle Inertial Reference Unit #2 (IRU-2) today. These cold starts are used to maintain the IRUs and ensure their longevity. The spacecraft will execute a series of off-point maneuvers after the power cycle. These will be done in all three axes, so images will appear to move left to right, nod up and down, and roll to and fro. Once the testing and calibrations are over SDO will return to routine science data collection.

During the calibration activity science data may be missing, blurred, or shifted.

Website Status Update - Data Outage

Power is out at the Stanford data site due to the current atmospheric river. Power is being restored to the university and the JSOC should be back in operations soon. The data is stored at the SDO ground station and will be available once power is restored.

Happy Launch Anniversary to SDO!

SDO was launched into orbit 13 years ago yesterday, at 10:23 am ET on 11 Feb 2010. Thirteen years and millions of observations later, SDO is still producing excellent solar data. It is hard to pick out a favorite sequence of SDO data. But the Sun did provide us with a nice filament eruption a few days ago as an early anniversary present. If you look in the northern polar regions of this combined AIA 211 Å (red), 193 Å (green), and 171 Å (blue) video, you can see the dark filament rising up and breaking apart. It appears to include one of the magnetic vortices we saw in the last Solar Cycle.

These polar filaments are a key part of removing the previous cycle's magnetic field from the poles of the Sun. As Solar Cycle 25 field erupts near the equator, some of it moves towards the poles where it meets the last remaining magnetic field of Solar Cycle 24. The fields tend to have opposite directions and they form a filament where they meet. This filament will circle the pole. Some of the oddity in this movie is seeing the plasma move around the pole in both directions.

The Sun will continue to surprise us, in SDO's 13th year and probably for many years to come.

I would like to thank the people who built and launched SDO, it has been an amazing observatory. I congratulate the people who run SDO on keeping this fantastic tool on station and performing great!

SDO is GO!

Perihelion Interrupts Instrument Calibrations

SDO executed the EVE FOV and HMI/AIA Flatfield instrument calibration maneuvers yesterday, 04 Jan 2023, at 1415 UTC (9:15 am ET) and 1730 UTC (12:30 pm ET), respectively. During these maneuvers, at 1617 UTC (11:17 am ET) the Earth reached perihelion, the point in its orbit when it is closest to the Sun. Here is a picture comparing AIA 1600 images at 1649 UTC (10:49 am ET, right) and 04 Jul 2022, 0711 UTC (03:11 am ET, during DST, on left) when the Earth is farthest from the Sun.

The blues lines are drawn to touch the poles of the Sun in the image from last July. You can see that the Sun appears to be a bit larger near perihelion than at apohelion. The SDO telescopes cannot change the size of their images and HMI in particular had to allow for this change in apparent size when designing the optics.

Happy Perihelion 2023!

Data Outage is Being Fixed

We apologize for the lack of SDO data over the long weekend. A major software update was done last week and the system was released to production too early. The issues are being fixed, partial connectivity has been restored, and full service should be restored soon.