On a dark late December winter night the United States military launched its secretive X-37B spaceplane atop a Falcon 9 heavy rocket from Kennedy Space Center. After watching the rocket slip from sight and the side boosters return nothing was seen from the spaceplane until the night of February 7, 2024 when amateur satellite observer Tomi Simola found something unusual, read his story below… Read more: The Hunt for OTV-7 Into the Dark At 01:07 UTC December 29, 2023, the US Space Force (USSF) launched their latest X-37B spaceplane mission referred to at Orbital Test Vehicle (OTV) 7 into a ..read more

We often post data online showing the results of a Doppler analysis. The concepts can be a bit intimidating to understand but with a little explanation it’s accessible to anyone. Read more: Understand Doppler Analysis What is the Doppler Effect? When something emits electromagnetic radiation and is moving relative to an observer the observed wavelength of the emitting radiation will be different. Essentially when things are moving their movement effects how the waves of radiation arrive at the observer. If they are moving toward each other the wave crests successively arrive earlier thereby de ..read more

Recent media reports indicate the US has developed a way to track the recent Chinese airships passing over North America. Here, a hypothesis is offered on how his may work and how observers can contribute. In July of 2022, the Chinese commercial JILIN Earth imaging constellation of satellites was found to be emitting strange short burst data signals on spectrum reserved for the mobile-satellite (Earth-to-Space and visa-versa) radio service. This observation while curious at first caused the author to reconsider the meaning of that observation after the recent arrival of a large Chinese airship ..read more

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. Close Encounters with the Moon As Chang’e 5 made it’s way closer to the Earth-Moon system radio positional data was used to develop a state vector and that state vector ..read more

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 ..read more

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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. A Look at the Data Structure In the past I’ve worked with GNURadio in order to process recordings of telemetry and data from several different satell ..read more

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. Telemetry Beacon The LES-5 telemetry beacon emits on 236.750MHz.  It uses BPSK at 100 bps. “The doubled carrier is biphase-modulated (±90°) by the 100/sec telemetry bit stream.” Page 39, Lincoln Experimental Satellite-5 ..read more

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 determine 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 orbit 53 year ..read more

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? Molniya Orbits Satellites are placed into Molniya orbits primarily to allow their payloads to ..read more