Mysterious ‘Pips’ from the Chinese JILIN Constellation

Why is an imaging satellite constellation acting like a mobile-satellite communications system?

China’s first self-developed commercial remote sensing satellite system known as JILIN is sending strange wideband data pips in a quiet piece of spectrum on L-band. The JILIN system is operated by Chang Guang Satellite Technology Company in Beijing. No public references have been found by the author about what these emissions from the satellites purpose is.

Continue reading “Mysterious ‘Pips’ from the Chinese JILIN Constellation”
Advertisement

You can call me Dmitry Meyer…

History Repeats Itself

Russia operates a constellation of satellites in high Earth orbit called Meridian (меридиан). These satellites perform a critical communications purpose for Russia as much of its land mass is not well served by geostationary satellites. Therefore, you would think this constellation would be held to the highest operational level. Well it’s not as radio amateurs have observed. This fact could raise questions about Russia’s ability and preparedness to act on their recent veiled threats of nuclear war.

Continue reading “You can call me Dmitry Meyer…”

Chang’e 5 Returns to the Moon

Chang’e 5 has quietly departed from the Sun-Earth L1 point to enter a distant retrograde orbit (DRO) of the Moon, a first.

Pre-empting NASA’s planned 1st use of the orbit during Exploration Mission 1 later this year.

Silence from China.

Off Station

In mid August 2021, the Chang’e 5 service module without any notice was noted to not be on station near the Sun-Earth L1 point where it had been since mid-March 2021. Observers were quick to reacquire the spacecraft’s X-band beacon and it was not long before it was clear from the data that Chang’e 5 was headed back to the Earth-Moon system where it would ultimately enter a Distant Retrograde Orbit (DRO) of the Moon.

Continue reading “Chang’e 5 Returns to the Moon”

Understanding LES-5’s Power System Status

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.

Continue reading “Understanding LES-5’s Power System Status”

Recovering Iran’s NOUR 01 ‘Military Satellite’

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.

Continue reading “Recovering Iran’s NOUR 01 ‘Military Satellite’”

A Brief Look at LES-5’s Telemetry Format

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.

Continue reading “A Brief Look at LES-5’s Telemetry Format”

LES-5 – Hacking the Telemetry Beacon?

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.

Continue reading “LES-5 – Hacking the Telemetry Beacon?”

The Recovery of LES-5

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.

Continue reading “The Recovery of LES-5”

Meridian 9’s Odd Argument of Perigee…

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?

Continue reading “Meridian 9’s Odd Argument of Perigee…”

A Review: “Dawn, this is Golden Eagle”

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.

 

Continue reading “A Review: “Dawn, this is Golden Eagle””