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Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

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Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#11

Post by BenjiWiebe »

chrisseaton wrote: post #7
gmueckl wrote: post #5

Earlier quoted context omitted.

Looks like this is just data from the GPS receiver, mostly about where the rocket thinks it is at the moment. This doesn't strike me as particularly sensitive. Data from, say, sensors embedded in the engines would be much more interesting.

> This doesn't strike me as particularly sensitive. I'm no rocket scientist but I would have thought you'd want to encrypt and sign everything... by default. Otherwise how do you stop spoofing as well?

Spoofing is extremely difficult when you are pointing a highly directional dish antenna up into the air at a rocket.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#12

Post by rrmm »

gmueckl wrote: post #5
ex3ndr wrote: post #2

I feel that this data is trade secret - why it is not encrypted?

Looks like this is just data from the GPS receiver, mostly about where the rocket thinks it is at the moment. This doesn't strike me as particularly sensitive. Data from, say, sensors embedded in the engines would be much more interesting.

If they were carrying a national security payload, then having a gps feed of the second stage trajectory and target orbit would be less than ideal.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#13

Post by ylere »

ex3ndr wrote: post #2

I feel that this data is trade secret - why it is not encrypted?

People have been running full simulations of SpaceX vehicles just of on-screen telemetry and videos [0]. In the past, SpaceX has been very open towards these kind of efforts, they don't seem to mind at all.

[0] Example for SN9: https://www.youtube.com/watch?v=UeBtBidjlvk | https://flightclub.io/result?code=SN91

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#14

Post by ceejayoz »

rrmm wrote: post #12
gmueckl wrote: post #5

Earlier quoted context omitted.

Looks like this is just data from the GPS receiver, mostly about where the rocket thinks it is at the moment. This doesn't strike me as particularly sensitive. Data from, say, sensors embedded in the engines would be much more interesting.

If they were carrying a national security payload, then having a gps feed of the second stage trajectory and target orbit would be less than ideal.

Amateur astronomers are very good at spotting national security payloads after launch.

https://www.theatlantic.com/technology/archive/2016/06/mappi...

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#17

Post by magicalhippo »

ex3ndr wrote: post #2

I feel that this data is trade secret - why it is not encrypted?

I imagine it adds latency, which at the very least means more data is lost in case of accident, which can make it harder to know what went wrong.

It also adds an additional failure point, as a single bit error during encryption can scramble an entire data packet or worse, rather than just invalidating a single sensor reading.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#18

Post by Cthulhu_ »

_Microft wrote: post #6

Some sleuths repaired/decoded a corrupted video file from (the first?) splashdown of a Falcon 9 in the ocean a few years ago [0], so maybe someone is able to tease out some information from the recorded binary data as well? They only searched for obvious string data so far. It's a different beast of course, as the structure and meaning of the data is basically unknown in contrast to the known format of a video file.…

I'm kinda hoping they'll publish some specs about at least part of their transmission data, I mean given that it's not encrypted either means it's not critical, or encryption is too costly. I can imagine that commands the other way do have some kind of encryption.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#19

Post by rrmm »

ceejayoz wrote: post #14
rrmm wrote: post #12

Earlier quoted context omitted.

If they were carrying a national security payload, then having a gps feed of the second stage trajectory and target orbit would be less than ideal.

Amateur astronomers are very good at spotting national security payloads after launch. https://www.theatlantic.com/technology/archive/2016/06/mappi...

Yup. Easy to do for most adversary nation-states as well, but the NRO still doesn't allow the SpaceX livestream to follow stage 2.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#20

Post by Cthulhu_ »

ceejayoz wrote: post #14
rrmm wrote: post #12

Earlier quoted context omitted.

If they were carrying a national security payload, then having a gps feed of the second stage trajectory and target orbit would be less than ideal.

Amateur astronomers are very good at spotting national security payloads after launch. https://www.theatlantic.com/technology/archive/2016/06/mappi...

And if amateur astronomers can do it, a well-funded national space agency can do it even better. I'm 100% sure that any launch is picked up via radar and sattelites and the like when they happen, and various properties extracted and extrapolated to determine their target orbit.

That said, I wouldn't be surprised if some known launches also contained some unknown payloads. Stealth technology on a satellite would probably thwart detection in space well enough.

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