Where the wild satellites fly Weather data directly from the source

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A contribution by Patrick Krämer.

Satellites have been causing excitement not only since Lena’s triumph at the Eurovision Song Contest. What’s cooler than sophisticated machines orbiting the Earth, gathering and sending information? Rhetorical question. For the average consumer, however, they are quite far away. Not only because they’re floating in orbit, but also because you’ll probably never get access to their data, right?

Wrong thinking! A friend already showed me a few months ago that it is possible to receive satellite images directly from American NOAA weather satellites without any special know-how.

Step 1 – Preparation is half the battle

The project took off on a very boring quarantine afternoon. The theoretical knowledge of how and that you can tap into the NOAA satellites I already had, as I said. And a suitable receiver for the satellite data (for example an old DVB-T USB stick) was also already in my possession. The last – and still missing – piece of the puzzle: a suitable antenna.

After some pondering, I had the thought of using a radio antenna (mounted on the roof anyway). The frequencies are at least in the same range (up to 108MHz radio, NOAA satellites from 137MHz). So it was worth a try.

My first attempts with the roof radio antenna quickly showed that the endeavor is not completely outlandish. But a little fine-tuning couldn’t hurt.

Step 2 – Houston, we need to do some readjustment

After a bit of playing around with the recording settings, the first recognizable images could be received, at least at high overflights. The variation comes from the fact that these satellites are not geostationary. It always varies at what angle they fly over a point on the earth. This is not the case with all satellites. For example, the Astra satellites we receive satellite television on have geostationary orbits.A large-scale satellite project that also uses non-geostationary satellites was recently launched by SpaceX.

Satellite images directly from the source. And here you can even already see something!

Step 3 – Automated Satellite Data Recording

Sitting in front of the computer and manually recording every time a satellite is in the area is of course quite inconvenient. Unacceptably cumbersome, so of course I promptly went in search of automation.

Here I came across the project wx-ground-station, which automatically starts and stops recording, converts the data into images and uploads them to the cloud.

After a fork of the project and some adjustments the scripts were adapted to my needs and could be used. In the meantime, the hardware was also expanded to include an FM filter (to avoid interference from radio stations) and a receiver amplifier.

Step 4 – Only shared satellite images are happy

However, these images are of no use to anyone (including me) if they gather dust in a lonely folder on my server. So in the last step I developed a web application to display the received data.

For this, many technologies familiar to me from my work at mmmake were also used: ASP.NET Core, TypeScript, KnockoutJS, Bootstrap, Docker. After a lengthy coding session, I was finally able to install the proof-of-concept on the server. Over the next few days, the application was then enhanced with features such as paging, sorting, a dark theme, an improved preview and the display of future satellite overflights.

What about you?

Did you also realize some extraordinary projects during the lockdown? Let me know or write to us directly.

The project is hosted at and is of course open source. You can find the code on GitHub.

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