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I'm a bit shocked at how low bandwith was allocated. 421 Megabytes per day is the theoretical upper limit. 16 Terabytes for the entire mission. I have more bulk storage in my desktop.
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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
I highly suspect that China (and almost every other country) are not the issue. Chinese and the whole international scientific community will profit immensely from the data coming from James Webb, so I don't think the Chinese have any interest in sabotaging the project. More dangerous would be some average joe, somewhere who would try to mess with it for the lulz.
One would wish that for budget-exponentially-overrun taxpayer-funded infrastructure, there would be open-source decoding information available.
Even in CS papers directly dealing with a piece of software there is no obligation to publish code.
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Yes, CCSDS Magenta and Blue reference books mandate AES-256-GCM as a minimum for data encryption and mandate that encryption and authentication should be used, particularly for commands/uplink. Sliding scale of requirements based on application of course - your cubesat's imaging system is less critical than the flight termination system on a manned mission, for instance.
Fwiw, sat c&c is the one thing you're allowed to use encryption on the Amateur radio bands for.
Does anyone know offhand when we should receive the first images?
2.0 % observation calibration
4.9 % instrument calibration
7.9 % solar system (comets, asteroids, kuiper belt objects, etc)
16.1 % exoplanets
17.2 % nearby galaxies
20.4 % galactic (debris disks, etc)
31.5 % distant galaxies and cosmology
This doc was drafted in 2012, and so this might've already changed or will be: https://www.stsci.edu/jwst/about/history/science-operations-...
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But in a really open project, the design of the whole lot would be on the web, and the data sent back would be sitting on an FTP server somewhere for anyone to download and use. In many ways, an open project is cheaper to do than a behind-closed-doors project where every new contractor needs to get access to only the bits of the project they need access to, and misunderstandings happen because not everyone has enough…
> the data sent back would be sitting on an FTP server somewhere for anyone to download and use I'm sure they could actually do that without too much fuss. But it would require significant amounts of scientist time to document those datasets to enable others to use them for any arbitrary dataset . I'm sure we'll see fully open data sets from JWST appear, but lots of the stuff it collects isn't going to be interesting…
Once the data is collected and downloaded it is added to the catalog with all of that metadata attached. Then it's a matter of opening up that catalog to the public, although I'm guessing the downloads will be quite sizeable so the bandwidth could be an issue.
The trick to making this work is to integrate the publishing into the workflow so it doesn't require any additional effort on the part of anyone.
One would wish that for budget-exponentially-overrun taxpayer-funded infrastructure, there would be open-source decoding information available.
Science in general still basically operates on the "NASA invented xyz while going to the moon"-model from the 20th century. Things get developed and then trickle into industry via back-channels (or people moving) but the idea of open-source is still both culturally alien and legally suspect. Even in CS papers directly dealing with a piece of software there is no obligation to publish code.
I'm a bit shocked at how low bandwith was allocated. 421 Megabytes per day is the theoretical upper limit. 16 Terabytes for the entire mission. I have more bulk storage in my desktop.
That’s insane. Where did you read that?
Does anyone know offhand when we should receive the first images?
Of some interest, this is the proposed imaging breakdown by time: 2.0 % observation calibration 4.9 % instrument calibration 7.9 % solar system (comets, asteroids, kuiper belt objects, etc) 16.1 % exoplanets 17.2 % nearby galaxies 20.4 % galactic (debris disks, etc) 31.5 % distant galaxies and cosmology There's a whole huge breakdown of what instrumentation calibration entails: https://www.stsci.edu/jwst/about-jwst/h…
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Fwiw, sat c&c is the one thing you're allowed to use encryption on the Amateur radio bands for.
how is that enforceable? you can't determine what the encrypted communication is.