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Lovely sight from Silbury Hill tonight. Quite easily naked eye including a fair chunk of the tail. Just managed to capture it before it grazed the horizon
Great project – Robin is a pioneer.
Taking inspiration Emil Kraaikamp deep sky images using CMOS cameras at fast(ish) frame rates using big scopes – I wonder if the chopper could be replaced with a CMOS camera. If the camera was run at 60Hz (twice as fast as the Crab’s pulse rate). All even numbered frames were stacked together and the same with odd numbered frames. Then the two images would be subtracted from each other. Only the light from the pulsar would remain – proving the pulse rate?
It would rely on a bit of luck with the timing – if the capture started at the maxima or minima there would be no difference in the pulsar’s brightness between the frames. Also I’m not sure you could trust the camera to run at a constant speed and not drop frames whilst capturing. Finally whilst the read noise very low on CMOS chips I’m not sure there would be enough flux to overcome it.
With all this thinking I might need a lie down…
You could try using my website https://eclipsingstars.org/ to search for observable candidates. You can’t specify future dates; however can update observing sites and look stars available tonight for all your sites.
Eliot
Thanks Mark.
I’ve updated the website with a sort by magnitude difference option. It calculate the difference in magnitude between the faintest and brightest, and then re-orders the list with the greatest difference in magnitude first.
The sort was fairly trivial; however I noticed that the GCVS magnitude data was more complex than I originally thought (I should have learnt this by now). I’ve updated my catalog of eclipsing stars accordingly.
A few things to note:
- GVCS uses Min1 and Min2 magnitudes this site just uses the faintest of these.
- If the Minimum or Maximum magnitude GCVS is not in V or is missing then the star is omitted.
- GVCS list magnitudes with a “<” or “>” indicating the limiting magnitudes I treat both these cases as the faintest magnitude.
- GVCS also lists magnitudes in brackets i.e. “()” here I add this value to the maximum value to get the sites faintest value.
The intent of this site is to provide observers with just enough information to quickly decide which stars might be of interested that night. As such compromises have to be made to simplify the catalog data available. The links to the source catalog(s) can be used to get more detailed information.
I have merged Krakow University’s catalog (TIDAK?) with GCVS. The website uses the TIDAK epoch and period where possible to calculate the eclipse timings. All bar about 10 stars in the TIDAK catalog are matched to GCVS, however there are almost twice as many eclipsing binaries in the GCVS than in TIDAK. I have also included GCVS stars with a non-eclipsing type that are listed in TIDAK. There has been some additional data sanitisation to remove stars with incomplete data. Hopefully this shouldn’t affect most observers, but please comment here if you are.
I thought it might be useful to add the spectral types, and links to the catalogs where the data was obtained. I would have liked to added links to VSX as well, but there is no easy way to build the link from the star name. An obvious omission is a link to SIMBAD, which I will put in a future release.
Briefly scanning the GCVS data file the other variables that look as if they fit this format are Pulsating Variable Stars, although given the long periods knowing the time of the maxima or minima might not be as much use.
Do you have any links to those other applications it would be good to compare and contrast?
Looking at the Krakow University’s site there appears to be to files:
http://www.as.up.krakow.pl/ephem/allstars-cat.txt
and
http://www.as.up.krakow.pl/ephem/EPHEM.TXT
They both look like they contain the same data. The EPHEM.TXT looks easier to read. There isn’t a field for the percentage of the period the eclipse takes part for. It might be nice merge this with the GCVS, but that does raise questions of how to show where data originated from.
Yes sorry should have said that Longitude is positive going East so La Palma will be 343. I was thinking of implementing -17 or 17W, but at a minimum I’ll add a note to the site.
I did a quick search of the Transient Name Server and there appears to be no reported events events since the 1st March within 5 degrees of M51. Here are the search criteria I used.
I’m still waiting for the cameras to come from China. With economy shipping then sorting out the import duties they could be a few weeks yet.
I found on ebay 2 Osprey 230 video capture cards for £6 from the UK. I’m going to look into the Climax Digital usb grabbers as I have an old laptop that I can use to get a mobile test system up and running.
