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Would it be possible to receive the transmissions from JWST (James Webb Space Telescope) as an amateur, building your own antenna?

Would the transmissions be encrypted?

One source cites it using: S-band at 2270.5 MHz to transmit telemetry and that the science data will be transmitted in K-band at 29.5 GHz, with a rate of up to 28 Mbps.

https://destevez.net/2021/12/decoding-james-webb-space-telescope/

BrendanLuke15
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Jonathan DS
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    I don't have enough for a full answer, but someone can pick up the pieces I'm leaving in this comment and turn it into one: NASA uses the DSN (https://eyes.nasa.gov/dsn/dsn.html) to communicate with JWST. With a 34-meter parabolic dish, the S-band telemetry is coming in at -121 dBm and the K-band is coming in at -98 dBm. That's after a dish antenna gain of 50-80 dB, depending on the band. – Tristan Jan 20 '22 at 02:04
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    different but related: Hijacked space data, notable instances of recovering images or other goodies from someone else's space mission? – uhoh Jan 20 '22 at 02:43
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    also different, but possibly related: https://space.stackexchange.com/questions/50015/does-the-juno-spacecraft-have-an-open-signal-by-design/50025#50025 – Ryan C Jul 16 '22 at 02:26
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    From what I can gather, yes. According to NASA, one year after the data has been downloaded by the observer, they will make it available for public consumption, exactly as they have done with ESA/Hubble. Here ya go: https://www.jwst.nasa.gov/content/forScientists/faqScientists.html#policies – ChairmanMeow Jul 18 '22 at 21:01
  • The transmissions are almost certainly encrypted because the data rate is so high and the data being transmitted is so complex. If we are transferring data at 28 Mbps, then it certainly isn't an analog signal just spewing photos line-by-line (like some Earth observation satellites) and this already significantly complicates amateur radio decryption. I find it very unlikely that we will see amateur decoding of scientific data intercepted from JWST – Dragongeek Jul 19 '22 at 18:46
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    @Dragongeek An ordinary transmission protocol would suffice, no need for encryption. Only the uplink needs to be protected. However, look at Tristan's comment--that's outside the amateur realm. – Loren Pechtel Jul 22 '22 at 05:20
  • @LorenPechtel Are there any radio protocols capable of transmitting 28 Mbps that don't already intrinsically have some sort of encryption? Even if it is "unencrypted", the amount of checksums, redundancy features, compression algorithms etc. would render the data unreadable without the protocol's documentation in hand (or a lot of reverse engineering). That aside, there is national security. While all the data from JWST will eventually be public, first dibs is important to the scientific community and the US wouldn't want eg. Chinese scientists "stealing" the "low-hanging" discoveries. – Dragongeek Jul 22 '22 at 08:35
  • @Dragongeek Yeah, you would certainly have to know the protocol. I suspect that information is available, though. – Loren Pechtel Jul 22 '22 at 14:04

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Yes, it is possible to detect the S band telemetry from JWST as an amateur, and it has been done with a 6.1m dish. Hams have built dishes this big. The source you listed details this, and was written by a ham. The telemetry does not appear to be encrypted.

To receive the Ka band science data would require a much bigger antenna on the order of an 18 meter dish due to the signal strength and wide bandwidth. I cannot find an authoritative source on if the science downlink is encrypted.

John
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