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I’m observing V404 Cyg again tonight this time using 30s exposures in Ic. The lightcurve so far tonight is attached. The mean Ic mag is around 10.4 and there are variations of a few tenths of a mag. Nothing like as spectacular as a few nights ago.
Richard,
The McDonald data is very nice. It shows what can be done with a 2.1m telescope and a specially designed photometer running with a 2s cadence. The Argos photometer is described here.
I managed a very short run of less than an hour last night in a short clear patch. There was a lot of variation (> 1 mag). Peak mags were 9.8 in Ic, 11.8 in V.
Michael,
I’ve never seen an eclipse from an aircraft but it clearly gives a completely different perspective on the various wide-angle phenomena, particularly the shadow. Thanks for posting these images. It looks like you had clear windows. I know that some of the eclipse flights had real problems with ice on the windows.
Nick.
Just listened to it. It sounded like a radio adaptation of the early part of Martin’s book with several of the facts changed for dramatic effect. I liked the quote “Does anybody actually read the BAA Journal?”. It’s not every day that you get something like that on Radio 4!
And he did a very good Radio 4 adaptation of Steven Baxter’s alternative history of the Apollo programme, Voyage. I’ve set my recorder for Monday afternoon.
Council on Wednesday agreed that the BAA should produce a DVD of this eclipse. This will include video and stills of the total and partial. We would particularly like to have material from groups around the country who set up public events to observe the partial.
I’ll make a more detailed announcement shortly which will include details of how to submit material.
Nick.
Mike,
That’s a great interview. Do you think they worked out the acronym for your travel group’s name? Remind me to get an autograph next time we meet!
I agree that the shadow bands were very prominent. I did help that there was a very large expanse of white “sheet” to see them on but I’m sure that the very clear atmospheric conditions helped too.
Nick.
Thanks Grant and Gary. It does seem that it was rather hit and miss in the UK but many people saw it.
I’ve just watched my recording of the BBC’s Stargazing Live coverage. I wonder if I can charge them for the cleaning bills that resulted from me throwing stuff at the TV. It seems to me that it would be a good idea for the BBC to actually have someone who knows something about what you see during a total eclipse so they can explain it to the audience rather than having celebs sprouting total nonsense. Perhaps that is too radical an idea?
I’ve spent the day processing my video and stills. Here are some links to stills and video captured in Svalbard on Friday. I apologise for the commentary on the video. It was -21C or so and my brain had died. I do get the impression that the eclipse was “incredible” or “amazing” though.
Nick.
David,
I think it has been suspended for a month while Stargazing Live is on. It’s due back in April.
Nick.
Stan,
The key point is that any filter must go over the front end, or objective, of the telescope. It is not safe to use filters at the backend, i.e. near the eyepiece.
I have a C6 and observe the sun using a full-aperture filter made from Baader Solar film. You can buy this film from a number of UK suppliers and make it into a filter that fits over the objective of your telescope. I made a suitable filter using cardboard and tape as shown in the picture below. Make sure that this fits snugly over the objective so that there is no danger of it coming off when you are looking through the scope.
Let me know if you need any more info.
Nick.
William,
Michael’s pics are excellent. Seeing it in a wide field really shows how bright it was. I wish I’d seen it!
Nick.
Mike,
I think the adopted rotation period is 2.6 hrs with a lightcure amplitude of around 0.2 mags. That means that I should have two rotations on the image set that I took on close approach night but I haven’t managed to find the time to do the initial analysis yet. Richard Miles has been helping me with the details and we hope to have something soon. The lightcurve may even show the effects of the small moon. Keep an eye on the ARPS page for more info.
You’re right that the motion was fast but the asteroid was so bright it was detectable with small instruments. Most of my images were made using a 72mm f/6 WO Megrez refractor and CCD tracked at sidereal rate. The wide field makes photometric reduction easier since there are lots of suitable reference stars visible.
Nick.
Peter,
Good to see your results too. I think we were very lucky with the weather for this event. Hopefully we should be able to extract a good light curve from all of this data.
Nick.
Thanks Gary. Here’s an animation from some of the frames.
Last Saturday night, January 10, I left a camera running taking 60s images of this comet. I have now stacked these into groups of 20 and made an animation from the resulting 8 frames. The mid-times of these frames are from 2015-01-10 17:54:38 to 20:27:34 so just around 2.5 hr. The FoV is 68’x52′ with approximately N up. If you look carefully you can see motion of features down the tail over this short period.
The tail of this comet really does change dramatically from day to day. One of the advantages that we have now is that we can get images taken from around the globe and this allows us to get really good time resolution. The images below are all from the last night and they show tail changes over a matter of hours. Please, please, please, if you are submitting images include field of view/scale and orientation info. Without this we need to do a lot of guessing when we rescale images to look at things like this.
Nick.
