More and more spacecraft are launching into LEO than ever before, and many owners utilize a rideshare program for an affordable ride to space. Along with this convenience, however, comes some uncertainty. In the days following a rideshare deployment, the satellites are all clustered together, which causes some congestion on the frequencies used for commanding and receiving telemetry from the satellite. Most operators do not have the luxury that large operators like NASA or and the DOD have – dedicated ground stations networked for ideal communications. Ground Station as a Service providers do an excellent job juggling their growing list of clients, but at the end of the day, only so much ground hardware exists, and everyone in the industry needs to share those assets. This can lead to long periods of uncertainty before that much anticipated “First Contact”.
To assist alleviate this, most operators rely on a short, but data filled, beacon burst on a regular interval, so that even in the congested frequency bands, a well-timed recording on an antenna can ease the minds of Mission Operations with signs of life. While these beacons can be collected from the same hardware that commanding utilizes, this would limit collections to brief windows, a handful of times per day at best.
Enter – SatNOGS. SatNOGS is an Open Source global network of satellite ground-stations. A grass-roots project, this network sees average people standing up antennas of various shapes, sizes, and specifications to listen in for signals from orbiting assets, cataloguing and rating these “observations” if they see what they expect or not. It’s powered by an evolving software client which uses a standard, compact packet defining the satellites orbit, known as Two Line Elements (TLE), to determine where and when a satellite registered in their databases is passing overhead and can task these ground stations to listen and record their broadcasts as they do. With details such as the modulation, baud rate, and center frequencies, these stations are capable of not only listening in but decoding these beacons, providing data for satellite operators to then take and parse into usable information about their satellite.
Rogue has utilized the SatNOGS network for both of our missions to date, first on Barry-1 where he gained the attention of many of the ground station operators in the SatNOGS network with his MIDI beacon – singing Ode to Joy across the sky. You can still find recent observations with his song as he nears orbital decay by looking through recent postings.
Want to see the great work that the folks at SatNOGS accomplish? Best place to start to dive right in is:
From here you can navigate to Observations > Browse and begin searching through their extensive list of already tracked satellites. Using the filters at the top of the browse page, you can narrow down your search by Satellite and the start and end times you want to see observations within. You can effectively narrow down your search to successful observations by checking only the Green Check status icon.
Once you have narrowed your search to your liking, clicking on the ID of an observation shows you all the details collected, including station information, radio details, a plot of the satellites track overhead, and the data itself. Each page showcases a waterfall recording image, a .jpg of the signal against the background noise over the course of the observation. Each blip you see indicates a transmission, and if the observation was successful, you should see a series of blips right down the center line, like this recent observation of our current mission – OTP-2:
SATNOGS Waterfall
The Rogue team is deeply appreciative of all of the volunteers over at SatNOGS – our mission team would be much more stressed if it weren’t for their diligence and the data we collect from these sources.
So head over to SatNOGS – browse around a bit and see what you can find! And while you are there, take a listen to the audio on some of our beacons (hint, the MIDIs look like that fuzzy part of the waterfall above!) – can you recognize the tune that OTP-2 is singing? It’s origin has had a huge influence on our Mission Director and many other astrodynamicists in the industry…