The Admiral

The crop factor is irrelevant to my mind. Assuming that your images are processed in exactly the same way, then one should be twice the size of the other. If you bin one and not the other, or if you crop the frame differently in processing, then that could account for it. Another thing springs to mind, depending on your settings, DSS will only give you a resultant image for which data in all frames is available. So, if there is significant drift over the imaging period, such that the frames don't completely overlap, then the image that DSS will produce will only cover the region where there is overlap, and so will cover a smaller field. Such 'hidden' cropping could account for it. Ian

Can't offer an explanation, but most of the brighter stars all over the field seem to show some evidence of it. Ian

Forgive the inane question, but is it what looks like an open cluster, or one of the bright objects? Ian

Welcome to the forum Geminids. A couple of years ago Steve Nickolls and myself wanted to get more information on the head echos. We were using a script which I had written for logging meteors, not the same as the referenced Brit Astro ones, and although I forget the details now, I had sort of concluded that a faster FFT was likely needed. IIRC the FFT cycles every 33ms, which is a bit slow for head echoes I think. Mind you, I know little about FFTs, and there may well be a cunning plan to extract more information! Ian

Well, that just goes to show what can be done with the ultimate Alt-Az mount - one that is stationary! Great perseverance there AA, a fine achievement. Ian

Even more strange (to me!) is that if you turn on the 'Night Blight' layer some of our local so called dark sites have no measurements in them! So how do they conclude that? Mind you, I'm not sure exactly what that layer is representing. Ian

Well to my mind, our theoretical abilities are limited by our our mental abilities, which don't demand much by way of resources. Proving our theories does take resources, but in the grand scheme of things, not a lot, and are in any event dictated by what the laws of physics (and computing power) allow us to do. Leaving our planet, on the other hand, will ultimately be dictated by the physical limitations of our bodies, about which I don't think we can do much, even if the resources were to be available. My twopence worth. Ian

That's nice! Now I didn't see that one at all! Ian

Will Spectrum Lab run satisfactorily on a RPi? I've always thought, possibly wrongly, that the FFT process demanded quite a bit of processing power, not to mention a 192kHz soundcard. I've set mine running at the moment to see what is coming through. Ian

. But I'm truly amazed given your location! It would be interesting to establish whether this is from any antenna backfire or the normal forward lobes (even more amazing!). I know little of long distance radio propagation, but I also wonder if it also down to some particular conditions that currently favour it, and therefore might not be reliable. DXers can obviously provide some insight here. Are you going to run for a period now? Ian

Indeed, I feel your excitement! What makes me think it is, is because there is a sharp descending frequency transient, with a more intense region at the end. With bigger meteors, the intense region will extend along the time axis at the Graves (zero Doppler) frequency, to give the appearance of a hook. But I'm sure you know this. You are most likely to see those during the meteor showers. It'll be interesting to see how frequent you see them, and how they compare with measurements made from the South of England. It would still be interesting to try VOR stations that you are able to get aligned to. I suppose the problem then might be to see meteors along with the background carrier. That leads me to wonder if you could point your antenna much higher in the sky so that the sensitivity to the direct path is reduced, and maximise reception of backscatter. After all, some professional monitoring sites have the transmitter and receiver co-located. Just a thought. Ian PS. I use Heavens Above https://www.heavens-above.com/PassSummary.aspx?satid=25544&lat=47.322&lng=5.0415&loc=Dijon&alt=249&tz=CET centred on Dijon, and on the 'ground track' tab, with a result like this I find it easy to interpret, but need to be aware of the time difference between Dijon and here. But, each to his own.

Well it does look like a meteor! It would help though if there were some axes of the chart included. I assume for example that the RHS is the higher frequency side. What is the scale? Given that the ISS is about 4x higher than typical meteor trails I would have thought it might have been more visible (though perversely I've not found this to be true in practice, the meteors can can give a lot more signal). What time was the expected transit? I don't think the 13.24 pass would have been good, and the 16.34, 18.11, and 19.48 too far north of Dijon unless there are significant rear lobes. So that just leaves the 14.58 as a potentially viable one. And the next one at 21.25. I suppose you didn't have the Spyserver running from the south of England to correlate it did you? Ian

Congratulations! A nice feather to have in one's cap, but I think you are being too modest! Ian

That was one advantage of the Funcube, it would work straight into SpectrumLab, though as Biggardigger points out, it offers less control. Spectrum lab does have it's manual on line, but I confess I found it pretty hard going. A couple of years ago I would have been much more familiar with it, but time has erased much! Ian

That's true, but once onto the mainland isn't the problem likely to be the 1000+ metre high Cairngorms 200km away? I haven't done the maths, but would you expect the radio waves to diffract over the top? Your location surely gives a better Southwesterly view I'd have thought. That said, is a higher gain antenna likely to help? It looks as though there are some VOR beacons on Iceland that would be worth exploring, though their frequencies are around 100MHz. If you could get that to work it would open up a new avenue of interest! Ian