Today I wondered if I could detect a data stream from the JWST.
I've done this with ham radio satellites and INMARSAT, but what about objects much further away?
This thread will be a running tally of the project. So it is less of a how-to, and more a public notepad for you guys to follow along in case you were interested, or had something to add.
There are a few challenges as I see them now
A search produced some frequency ranges to answer for #2:
The best SDR I have is the SDRPlay2, which tops out at 2ghz. The RTL v4s only go to 1.7ghz. I'm going to need a receiver with higher range or a block down converter.
#4 is pretty easy to solve. NASA does it for us.
We can use a planetarium application and a script, along with NASA data, to plot the position of points important to this project.
The program I am using is called Stellarium. It is free and feature-rich. https://stellarium.org/
This repo contains a Stellarium script to plot the position of the James Webb Space Telescope (JWST) and the Sun-Earth-Moon-Barycenter L2 Lagrange (SEMB-L2) point using coordinates from the Nasa Horizons service.
github.com
This is the plot for ~10pm tonight.
The JWST will be fairly high to the east, clear of trees and obstructions. I'll have to adjust the data of course when we're ready for a measurement attempt.
You can see Sun-Earth L2 point in yellow off to the right. The JWST orbits these points.
L2 or the LaGrange Point 2 is a point in the solar system where objects can be placed and not have to use much or any fuel to stay in orbit.
In red, I've plotted Earth-Moon L4. This is for another experiment I've been planning since the bottom of last solar cycle, but since I just figured out this script, I thought I'd try mapping other points.
So it appears I have enough to at least start finding the RX gear and planning the antenna.
The coffee can antenna comes to mind, but I am thinking it won't be enough gain.
I do have a 22 inch dish with a 5ghz feed. This might be suitable with a custom 2.2ghz feed. Only way to know is to get an RX and test it out.
I'll update as I make some progress.
I've done this with ham radio satellites and INMARSAT, but what about objects much further away?
This thread will be a running tally of the project. So it is less of a how-to, and more a public notepad for you guys to follow along in case you were interested, or had something to add.
There are a few challenges as I see them now
- JWST is far away, orbiting around Earth-Sun L2 (a million miles) so signal might be very weak and hard to detect with small antennas.
- The spacecraft uses frequency bands outside of shack capabilities
- Once the freq is discovered, we need to design and build an antenna
- We still need to figure out where it is to point the antenna
A search produced some frequency ranges to answer for #2:
JWST uses S-band at 2270.5 MHz to transmit telemetry. The science data will be transmitted in K-band at 25.9 GHz, with a rate of up to 28 Mbps.
The best SDR I have is the SDRPlay2, which tops out at 2ghz. The RTL v4s only go to 1.7ghz. I'm going to need a receiver with higher range or a block down converter.
#4 is pretty easy to solve. NASA does it for us.
We can use a planetarium application and a script, along with NASA data, to plot the position of points important to this project.
The program I am using is called Stellarium. It is free and feature-rich. https://stellarium.org/
This repo contains a Stellarium script to plot the position of the James Webb Space Telescope (JWST) and the Sun-Earth-Moon-Barycenter L2 Lagrange (SEMB-L2) point using coordinates from the Nasa Horizons service.
GitHub - nbhasker/JWSTStellarium: Stellarium script to plot the position of the James Webb Space Telescope (JWST) and the SEMB-L2 Lagrange point using coordinates from Nasa Horizons
Stellarium script to plot the position of the James Webb Space Telescope (JWST) and the SEMB-L2 Lagrange point using coordinates from Nasa Horizons - nbhasker/JWSTStellarium
github.com
This is the plot for ~10pm tonight.
The JWST will be fairly high to the east, clear of trees and obstructions. I'll have to adjust the data of course when we're ready for a measurement attempt.
You can see Sun-Earth L2 point in yellow off to the right. The JWST orbits these points.
L2 or the LaGrange Point 2 is a point in the solar system where objects can be placed and not have to use much or any fuel to stay in orbit.
In red, I've plotted Earth-Moon L4. This is for another experiment I've been planning since the bottom of last solar cycle, but since I just figured out this script, I thought I'd try mapping other points.
So it appears I have enough to at least start finding the RX gear and planning the antenna.
The coffee can antenna comes to mind, but I am thinking it won't be enough gain.
I do have a 22 inch dish with a 5ghz feed. This might be suitable with a custom 2.2ghz feed. Only way to know is to get an RX and test it out.
I'll update as I make some progress.
