Brutkey

AkaSci 🛰🛰️
@AkaSci@fosstodon.org

Starlink satellite anomaly at 418 km altitude. Loss of comms, venting of the propulsion tank, a rapid decay in semi-major axis by about 4 km, and the release of a small number of trackable low relative velocity objects.

Starlink states that there is no risk to the ISS. The largely intact tumbling satellite will reenter the atmosphere in a few weeks.

No explanation for the cause of the low velocity objects. An explosion?

@sundogplanets@mastodon.social
1/n

Tweet from Starlink @Starlink On December 17, Starlink experienced an anomaly on satellite 35956, resulting in loss of communications with the vehicle at 418 km. The anomaly led to venting of the propulsion tank, a rapid decay in semi-major axis by about 4 km, and the release of a small number of trackable low relative velocity objects. SpaceX is coordinating with the @USSpaceForce and @NASA to monitor the objects. The satellite is largely intact, tumbling, and will reenter the Earth’s atmosphere and fully demise within weeks. The satellite's current trajectory will place it below the @Space_Station, posing no risk to the orbiting lab or its crew. As the world’s largest satellite constellation operator, we are deeply committed to space safety. We take these events seriously. Our engineers are rapidly working to root cause and mitigate the source of the anomaly and are already in the process of deploying software to our vehicles that increases protections against this type of event. https://x.com/Starlink/status/2001691802911289712
AkaSci 🛰🛰️
@AkaSci@fosstodon.org

I missed this post from LeoLabs on Dec 18, where they noted that 10s of debris objects were detected from the Starlink 35956 anomaly event of 17 Dec 2025.

They also assessed that the satellite’s initial drop in orbital altitude was likely caused by an internal energetic source (e.g., an explosion) rather than a collision with space debris or another object.

Ed Lu of LeoLabs posted today 100s of debris objects being tracked.

No info on fragment sizes or apogee.

No new word from SpaceX.
2/n

1. Tweet by Ed Lu @astroEdLu We @LeoLabs_Space are tracking hundreds of debris objects associated with @starlink 35396. As per usual, these objects tend to spread out along the orbital track, and have already spread out over 6000km. 2. Tweet thread from LeoLabs @LeoLabs_Space 1/ LeoLabs orbital diagnostics tools captured early evidence of the SpaceX Starlink 35956 fragment creation event on 17 Dec 2025. 2/ We quickly assessed that the satellite’s initial drop in orbital altitude was likely caused by an internal energetic source rather than a collision with space debris or another object. 3/ LeoLabs Global Radar Network immediately detected tens of objects in the vicinity of the satellite after the event. Additional fragments may have been produced — analysis is ongoing. 4/ Due to the low altitude of the event, fragments from this anomaly will likely de-orbit within a few weeks. 
Prof. Sam Lawler
@sundogplanets@mastodon.social

@AkaSci@fosstodon.org I call BS on that "no risk to the ISS" - if this satellite is only a few km lower altitude and just ejected a bunch of debris, there will definitely be ISS-altitude-crossing debris. But maybe the orbits don't intersect for the next few days? Would be nice if SpaceX specifically stated that.