The next couple of days we expect GRIFEX to re-enter, I’ve opened this thread to track it and publish updated TLE.
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It looks like that GRIFEX stopped transmitting unexpectedly (it hadn’t been re-entered) around 2024-02-18 23:22:12. Without signal is impossible to track its re-entry which is expected later today.
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GRIFEX is back alive!
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@jwc any idea what went wrong and the satellite was silent for ~12h? As the time value looks very rounded, could this be a kind of watchdog that resets the satellite after 12 hours?
By the way for those that scheduling in Network, please make sure from now on, that we approach the re-entry, to not schedule too far away in the future as the TLE/orbit of the satellite will change significantly. Another request, please when you schedule use the advanced settings to set custom horizon with value 0, this will allow us to use the whole pass duration for calculating the orbit when the TLE is not very accurate.
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Thanks for tracking! The beacon software has a memory leak and it has been crashing more frequently over the last few months. GRIFEX is transmitting based on commands that we scheduled early this morning. Our next pass here in Michigan is in about 6 hours. I’ll see if I can restart beacons then. It should be automatically rebooting any time now, which typically recovers the beacons.
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GRIFEX beacons are back online!
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It looks like I my guess was wrong, it seems that it will last at least one more day 
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AOS 15:21:39 UTC, Max El. 76 deg over Minsk, Huge QRM
TLE is almost perfect. The maximum frequency deviation in the apogee is about 800 Hz (regarding TLE).
Orbit has not changed much since yesterday.
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Here is a first attempt for updated TLE set, is not very accurate but better than the current:
GRIFEX
1 40379U 24051.75000000 .00000000 00000-0 12817-2 0 01
2 40379 99.0631 63.9902 0013668 123.6290 200.8708 16.27018943 05
grifex_51_v1.dat (1.5 KB)
sites.txt (5.7 KB)
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Such stability of the orbit at an altitude of 215 km is extremely amazing!
Maybe GRIFEX is captured by an American or Chinese military shuttle, a Russian satellite inspector or aliens? 
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let’s wait for the next batch of observations…
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A fix on the previous TLE set:
GRIFEX
1 40379U 24051.75000001 .00000000 00000-0 12804-2 0 08
2 40379 99.0631 62.7150 0013668 123.6290 199.7617 16.23558753 06
sites.txt (5.7 KB)
grifex_51_v3.dat (910 Bytes)
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It’s great to see the beacons continuing to be received!
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There is a new space-track.org TLE:
0 GRIFEX
1 40379U 15003D 24051.57144849 .03146737 34886-5 12356-2 0 9990
2 40379 99.0621 62.1307 0011352 129.2559 230.9735 16.23668558502091
And one update from the Network observations which I’m going to use in Network and DB:
GRIFEX
1 40379U 24051.80000000 .00000000 00000-0 12811-2 0 01
2 40379 99.0631 62.2165 0012302 117.2160 138.6306 16.25197477 07
grifex_51_v5.dat (945 Bytes)
sites.txt (5.7 KB)
Both fit pretty well the latest observations, will see for the next ones.
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Oh no, my favorite satellite for testing SatNOGS station and antennas… Need to find a new one now on UHF
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Still alive up there as of 45 min ago. 
SatNOGS Network - Observation 9067728 TLE still fitting great.
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There is a new TLE from space-track.org that fits better the latest observations:
0 GRIFEX
1 40379U 15003D 24051.75625529 .03982988 35035-5 13772-2 0 9995
2 40379 99.0617 62.3904 0011106 131.1863 229.0383 16.25203847502139
EDIT:
The same TLE propagated to 24052 epoch:
0 GRIFEX
1 40379U 15003D 24052.00000000 .00000000 00000-0 13772-2 0 00
2 40379 99.0617 62.7326 0011375 131.0363 215.1734 16.27143739 03
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Still flying as of 00:07 UTC as seen here at EM00
https://network.satnogs.org/observations/9070822/
Maybe it is tumbling as I saw deep fades during the pass.
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Looking at the dashboard for the time of your observation, it is definitely spinning around up there in some direction (sinusoidal temperature and magnetometer readings ) Grafana
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