Introduction As space becomes increasingly congested, contested, and commercialized, the need for reliable, secure, and professional-grade space situational awareness (SSA) has never been greater. While the democratization of satellite observation through open-source ground station networks appears promising, it presents significant under-discussed risks. This paper uses SatNOGS as a central example to explore the operational, economic, … Read more

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 … 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 … Read more

STEREO-A is coming home in the summer of 2023 for the first time since it was launched 17 years ago and is providing amateur astronomers with a unique opportunity to do some citizen science. The spacecraft has inferior conjunction with Earth on August 17, 2023 and will be approximately 8.2 million kilometres distant then. While … 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 this 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 … Read more

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 … Read more

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 … 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 … 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 … Read more

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 … Read more