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Decoding James Webb Space Telescope

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Re: Decoding James Webb Space Telescope

#3

One would wish that for budget-exponentially-overrun taxpayer-funded infrastructure, there would be open-source decoding information available.

I actually don’t know if they want to protect the data. I can imagine they might not want China or other countries listening in and potentially sending commands to the craft.

Does anyone know if there is typically encryption on the downlink? How about uplink commands? I guess we want those to be secured so only authenticated control can send commands

Re: Decoding James Webb Space Telescope

#4
post #3

One would wish that for budget-exponentially-overrun taxpayer-funded infrastructure, there would be open-source decoding information available.

I actually don’t know if they want to protect the data. I can imagine they might not want China or other countries listening in and potentially sending commands to the craft. Does anyone know if there is typically encryption on the downlink? How about uplink commands? I guess we want those to be secured so only authenticated control can send commands

There would have to be some sort of encryption or passkey or digital signature on commands, for sure. Otherwise some hobbyist in the middle of the Ocean on his yacht could be messing with the craft and taking pictures and there'd be no easy way to shut him down.

Re: Decoding James Webb Space Telescope

#9

One would wish that for budget-exponentially-overrun taxpayer-funded infrastructure, there would be open-source decoding information available.

This is just telemetry data which doesn’t have much general or scientific interest, i guess they could publish the protocol spec (honestly it probably is aquirable) but most of the fun for the kinds of people who want this data is going to be doing this reverse engineering themselves.

The real imaging data would require a much more significant dish to even receive (i can’t immediately find what it’s going to use, but I’m guessing something like a 40 meter dish) so there are approximately zero amateurs who could use such open source information.

Re: Decoding James Webb Space Telescope

#10
post #5

Does anyone know offhand when we should receive the first images?

About six months.

https://webbtelescope.org/quick-facts/mission-launch-quick-f...

> After reaching its orbit, Webb undergoes science and calibration testing. Then, regular science operations and images will begin to arrive, approximately six months after launch. However, it is normal to also take a series of "first light" images that may arrive slightly earlier.

It will take about a month for it to get out to the Sun-Earth L2 point which is 1.5M km (0.01 AU) from the Earth. For comparison, the Moon is 384k km away. The telescope will be 4x further away from the Earth than the Moon is.

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