ISS and meteor close call

[Tomatobro]

Recorded this morning.  Scary stuff! See how the ISS track and meteor almost coincide

[Coto]

Could you explain what we're seeing here? What kind of data was the ISS transmitting? Or did you transmit a radio wave signal to the ISS and measured the time it took to return? What about meteor detection? Doesn't that require at least two radio telescopes (one transmitting and one receiving) with them being miles apart?
(Sorry I'm new to radio astronomy and I'm trying to figure out how various things are observed! )

[Tomatobro]

Coto Hi and thanks for your interest

 

There is a radar station located in Dijon France. With simple kit you can detect the reflected radio signals using this radar from objects and ionised meteor trails high in the sky.

Because the radar sweeps back and forth the ISS station appears as a series of spikes or blips (depending on the software used) and these are the smaller spikes seen going diagonally from top left to bottom right in the image.

The meteor reflection is the larger of the spikes. There is only one spike as meteors are (usually) short lived and only reflect one sweep of the radar beam.

In reality the meteor posed no threat to ISS but its an interesting observation.

If you are interested in getting involved in meteor detection there are lots of websites (search " meteor detection using GRAVES ") and an article was published in Sky at night magazine on how to get started. Its not too difficult to get started. And there are threads on this forum you can read.

The software is free to download and use, The antenna can be constructed from copper water pipe from a DIY store. The receiver is one of the SDR (Software Defined Radio) types that plugs into a USB port on your computer. The whole setup can be put together for about the price of a decent eyepiece.

Hope this helps

Tomatobro

p.s. Tip on buying an SDR Dongle. Avoid cheap! A "Funcube Dongle Pro +" is the one to go for. Members of my local Astronomy club will bear me out on this.

[Coto]

Hi, thanks for the info!

If you see my other post you should see I’m currently building my own radio telescope for solar observations. I do have a few questions about the required equipment which can be found on the post (feel free to provide any info that might be helpful). Is meteor detecting much more difficult compared to solar observations? And what frequency do those radars transmit on? Where in the world are you receiving those signals? Do you experience any Doppler shift?

 

Thanks!

[The Admiral]

4 hours ago, Coto said:

Hi, thanks for the info! Is meteor detecting much more difficult compared to solar observations? And what frequency do those radars transmit on? Where in the world are you receiving those signals? Do you experience any Doppler shift

Relatively easy once you get set up. Graves transmits on about 143MHz from a site near Dijon, in a southerly direction, and with meteor detection doppler shift is what it's all about. The scatter can be detected widely around Europe with a simple Yagi. With the ISS you can expect a shift of about + or - 6kHz, horizon to horizon.

This long thread has a lot of information and links.

Ian

 

[Waddensky]

If you just want to get your feet wet, there are some online tools where you can eavesdrop on actual receivers tuned to Graves to listen for meteors.

[Tomatobro]

19 hours ago, Coto said:

Hi, thanks for the info!

If you see my other post you should see I’m currently building my own radio telescope for solar observations. I do have a few questions about the required equipment which can be found on the post (feel free to provide any info that might be helpful). Is meteor detecting much more difficult compared to solar observations? And what frequency do those radars transmit on? Where in the world are you receiving those signals? Do you experience any Doppler shift?

 

Thanks!

The only radio Solar obs I have done is using a satellite dish in response to a request to set something up for a school. I got hooked and wanted to see how far I could push the technology and ended up building my own receiver. There is a post somewhere on SGL of the dish and some results. I will try to find it for you.