A few weeks ago, we brought word to Reddit users [derekcz] and [Xerbot] managed to receive the 2232.5 MHz telemetry downlink from a Falcon 9 upper stage and pull out some interesting plain text strings. With even more software fiddling, the vehicle’s video streams were decoded, resulting in some absolutely breathtaking shots of the rocket and its payload from low Earth orbit.
Sadly, it looks like those heady days are now over, like [derekcz] reports that the downlink from the latest Falcon 9 mission was nothing but intelligible noise. Since the hardware and software on its end haven’t changed, the only logical conclusion is that SpaceX wasn’t too happy with radio amateurs eavesdropping on their rocket and decided to use some form of encryption.
Since this data has apparently been publicly broadcast for nearly a decade before anyone on the ground noticed it, it’s easy to see this as an overreaction. After all, what’s the harm when a pair of nerds with antennas hacked together glance at a stack of Starlink satellites? [derekcz] even thought that allowing hobbyists to capture these spatial renderings would bring the company some positive buzz, something Elon Musk never seems to get tired of.
On the other hand, we know that SpaceX is actively looking for more lucrative national security launch contracts for both the Falcon 9 and Falcon Heavy. For these sensitive government payloads, the normal telemetry data and on-screen space views are omitted from the company’s official live streams. It seems that the Pentagon would be very interested in knowing how citizens could obtain this information, and a guarantee from SpaceX that the link would be encrypted for all future flights could have helped smooth things out.
At the end of the post [derekcz] reflects a feeling we have recently heard from other amateur radio operators, namely that space could soon be off limits to us citizens. As older weather satellites begin to fail and are replaced by newer and inevitably more complex models, the days when satellite images with an RTL-SDR and a few lines of Python were retrieved are likely numbered.