Tuesday, August 23, 2022

Weak Geomagnetic Storm Claims an Old Satellite

Last Friday, August 19, the giant satellite service provider Intelsat reported that they had lost control of one of their older satellites, Galaxy 15.  They're attributing the loss of control to the mild geomagnetic storm that hit last Friday as a result of coronal mass ejections earlier in the week.

“The satellite is otherwise operating nominally, keeping earth pointing with all payload operations nominal,” Intelsat spokesperson Melissa Longo said.

While Intelsat is working to restore its ability to command the satellite, Longo said the company expects all customers to “have service continuity” until its Galaxy 33 replacement arrives in November.

Galaxy 15 is in geosynchronous orbit at 133 degrees west, providing satellite coverage to the Americas.  It was built by Orbital Sciences corp and launched in 2005.  Orbital Sciences has since been bought by Northrup Grumman, and they're now in the final stages of preparation on Galaxy 33.  SpaceX is expected to launch Galaxy 33 and 34 in October, and Galaxy 33 is to take over for 15 by November.  

It's fortuitous that the satellite that gets crippled by the geomagnetic storm was scheduled for replacement anyway, and it's not hard to think that the satellite's age might have something to do with it being damaged.  Strangely, this isn't the first time Intelsat lost control over this particular satellite. 

In 2010, the company lost contact with the satellite for over eight months before it finally began accepting commands from Intelsat's control center after its batteries fully drained and prompted a reset.

Geomagnetic storms are a feature in any solar cycle, and while cycle 25 is pretty much just getting started, it is starting out stronger than cycle 24.  Still, it's a long way from challenging even cycle 23, which we thought was pretty mild.  (Graph at the bottom of this page)  After all, 23 was the weakest cycle I'd lived through by that point.  The warning from NOAA for geomagnetic storms predicted G1-G3 depending on UTC date.   The scale runs from 1 to 5, so G3 is not an extremely strong storm.  Note that the chart says that the "Physical Measure" for a G3 storm is X1 and there were no X-class solar flares.  There were a couple of M-class (next class down from X) that were close enough in time to being a cannibal Coronal Mass Ejection storm

The wild card in how damaging a geomagnetic storm can be, though, isn't this scale but could be the Earth's magnetic field and how its weakening faster than has ever been seen before, while the north and south magnetic poles are simultaneously moving faster than has ever been seen before.  The magnetic field's protection from solar storms is critically important.

Intelsat Galaxy 15 in easier days.  



  1. Poor old G15. We used to get programming from them to "turn around" and rebroadcast to our subscribers.

  2. Hopefully they can kick it out of orbit once it's "decomissioned"...

    1. If they can't command it to get out of its assigned place in the GeoStationary Orbit, there's that new little "Mission Extension Vehicle" that Intelsat came up with that can latch onto the satellite and nudge it far enough out to not take up space there. The GSO is kind of "prime real estate" because so many services want access to it.

      If I understand things, there's one MEV up there now and another scheduled for '24.

    2. Just imagine how many MEV's Starship could put in orbit...