It’s be a quarter of a year since LES-5 was recovered and we began decoding telemetry. The spacecraft sends 128 words (8 bit bytes) every 10.24 seconds which is called a format. That format is comprised of four frames of 32 words. Of the 128 words eight are used for syncing and 24 used for parity checking. This leaves 96 that contain telemetry data. Until now we only fully understand eight of the words used for the Radio Frequency Interference (RFI) experiment, leaving 88 words with unknown meaning. What follows is how we determined the meaning of four more words that reveal the health of LES-5’s solar power system and the present rotational period of the spacecraft.
Iran’s new military satellite, NOUR 01, most interesting fact may not be that it resembles a college engineering experiment but rather that it may have a connection to a Mexican military payload launched quietly from New Zealand last year.
It’s also with great pleasure that I can share Scott Chapman, K4KDR’s story of how he found Iran’s NOUR 01 [45529, 2020-024A] radio emissions and confirmed it was alive and well in orbit and noted a twist to the story in a brief interview we had.
It’s not exactly every day that you get the chance to work with any data, let alone telemetry data from a 50-year-old satellite. However, thanks to Scott’s observations of LES-5 and subsequent investigation into its telemetry beacon, the opportunity arose. Based partly on the work of others, as well as what I’ve managed to glean from the technical documentation that has been gathered, I’d like to explain my process for processing data from LES-5.
LES-5 was recovered on March 24, 2020. Since then I have completed a fair amount of research on the spacecraft and collected a number of published papers on the results of the experimental mission. From those papers, I will lay out some possible methods to analyse the decoded telemetry from LES-5 such that we may be able to determine if the command receiver is still active.
On the afternoon of March 24, 2020 EDT, I noted a modulated carrier on 236.7487MHz. I wasn’t looking here by accident, I was looking for LES-5 and after almost 53 years in space and 49 years since it was suppose to have been switched off LES-5 [2866, 1967-066E] had been discovered alive.
What follows is a discussion of the methods used to identify the satellite as LES-5 and determination that the telemetry transmissions may have scientific value as if the spacecraft is sending meaningful telemetry, researchers may be able to obtain valuable information on how hardware launched into a high Earth orbit 53 years ago has faired.
Meridian 9 was successfully injected into orbit on February 20th, 2020. Unofficial reports indicated that the third stage of the Soyuz 2.1a rocket shut down prematurely and that the Fregat space tug needed to compensate to place the satellite into the desired orbit. Later it was noted the Argument of Perigee (AoP) for the satellite was not the typical Molniya value of 270 degrees. Was this an indication that the satellite was not placed into the correct orbit by the malfunction or something else?
A Front Row Seat
Space seems like a far away place that only nation states and large well financed companies dare to go and only the best funded minds can get a first hand glimpse of the goings on ‘out there’. In “Dawn, this is Golden Eagle”, Sven Grahn provides a motivational summary of a radio satellite tracker’s career and reveals how anyone with the interest and aptitude can obtain a front row seat on the goings on in space with the most modest means.
Not Lost in Space, Just Wandering?
On the afternoon of Sunday, September 8, 2019, I was leisurely monitoring deep space when I noted an S-band signal that shouldn’t have been where it was if all was normal with the GEO belt world… GOES-15 presently lives at 128W and GOES-17 at 137W, so what was a GOES N,O,P series spacecraft doing in between them? A quick check of Space-Track.org data revealed it was GOES-13. But why was it here and drifting westward? As we will see GOES-13 isn’t lost, it’s just wandering.
Queqiao was launched by China on May 25, 2018 towards the far side of the Moon where it ultimately took up shop at the Earth-Moon L2 point in a halo orbit. It’s mission is to provide communications for the first landing on the Moon’s far side by Chang’e 4.
On January 3, 2019, 02:26 UTC Chang’e 4 landed on the far side of the Moon ending over a fortnight of tracking the trajectory of the mission as it left Earth, arrived in lunar orbit made orbital adjustments and then finally landed. I discuss the results of our tracking attempts focusing mostly on the final analysis where the landing time was predicted and compare that to a final analysis performed after reviewing the crumbs of data shared from Chinese state media videos to see how close we got.