Tuesday 22 August 2023

A new North Korean satellite launch attempt upcoming [UPDATED]

Click map to enlarge

UPDATE (24 Aug 2023)

The launch took place around 18:50 UTC (so at nighttime this time) on August 23. The payload failed to reach orbit.

According to the North Korean State News Agency KCNA, the first and second stages worked nominally (the second stage failed during the May launch), but there was an "error in the emergency blasting system during the third-stage flight".

This sounds like the self-destruct mechanism was triggered by mistake.

KCNA reports that a third launch attempt will be conducted in October. Apparently, they have a lot of spare satellites and rockets in store...

[end of update]

North Korea has issued a Navigational Warning for a new satellite launch attempt from Sohae. The launch window runs from 23 August 15:00 UTC to 30 August 15:00 UTC.

The three hazard areas from HYDROPAC 2699/23 (blue in the map above)  are similar to those for the failed June launch attempt. They are different from the 2016 KMS-4 launch (shown in red in the map above, for comparison)

(more on the failed June attempt in a previous post here, which also discusses the two possible launch trajectories I have depicted in the map).

The text of Navigational Warning HYDROPAC 2699/23:

211953Z AUG 23
HYDROPAC 2699/23(91,92,94).
DNC 11, DNC 23.
   231500Z TO 301500Z AUG IN AREAS BOUND BY:
   A. 36-06.94N 123-33.11E, 35-24.52N 123-22.78E,
      35-20.02N 123-48.62E, 36-02.44N 123-59.18E.
   B. 34-05.90N 123-01.99E, 33-23.47N 122-51.88E,
      33-16.54N 123-29.66E, 33-58.97N 123-40.07E.
   C. 14-54.17N 128-40.10E, 11-19.30N 129-10.84E,
      11-26.81N 129-54.13E, 15-01.70N 129-24.05E.
2. CANCEL THIS MSG 301600Z AUG 23.

Tuesday 8 August 2023

The reentry of a Soyuz rocket stage over southern Australia on August 7

click map to enlarge


On 7 August 2023 at 13:20 UTC, Russia launched the first of it's improved GLONASS-K2 navigation satellites from Plesetsk Cosmodrome. The launch employed a Soyuz 2.1b rocket with a Fregat upper stage. The payload and the Fregat upper stage were subsequently catalogued in 19156 x 19135 km resp 19182 x 19005 km, 64.8 degree inclined Medium Earth Orbits (MEO), as catalogue numbers 57517 and 57518.

Some 40 minutes after the launch, people from southern Australia and Tasmania were treated to a spectacular sight of a bright slow-moving, fragmenting fireball that crossed the sky. Many eyewitness video's were posted on social media and poicked up by the News media: for a few fine examples see here, here, here and  here. Immediate suspicions were raised that this was space debris.

Indeed, the fireball was the Soyuz 3rd stage reentering the atmosphere. A Navigational Warning for space debris connected to this launch had been published earlier (HYDROPAC 2502/23), for an area south of Australia and Tasmania:

021113Z AUG 23
HYDROPAC 2502/23(75,76).
DNC 05, DNC 06.
   071300Z TO 071600Z AUG, ALTERNATE
   1300Z TO 1600Z DAILY 08 AND 09 AUG
   43-10.00S 148-55.00E, 53-30.00S 163-20.00E.
2. CANCEL THIS MSG 091700Z AUG 23.

The time window matches well with the Australian reentry sighting. The area defined by the Navigational Warning matches a launch into a ~63 degree inclined parking orbit from Plesetsk:

click map to enlarge


The Soyuz 2.1b rocket consists of four side boosters ('stage 1'), a core stage ('stage 2') and a third stage. On top of that is (for this launch) the Fregat upper stage. The Soyuz rocket brings the Fregat upper stage and GLONASS payload in a low parking orbit. From there, a series of firings of the Fregat stage bring the payload to 19150 km Medium Earth Orbit (MEO). The Fregat upper stage is left on orbit, but the Soyuz stages deorbit downrange from the launch site: the last of these stages, is the stage that reentered over southern Australia about half a revolution after the launch.

GLONASS is the Russian equivalent of GPS.