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Hi Dominic, Nice upgrade to the members pages, I’ve just uploaded an image to test out the new plate solving capability!
Is it still possible to add hyperlinks in the “About this image” text for each observation? Also, changing my profile image has been a bit hit-and-miss but haven’t tried again today yet so maybe that was just an issue yesterday.
Thanks, Mike
I guess most of you know this but spectra are now starting to be posted on the ARAS web page for this nova. Well worth checking regularly as the nova develops.
Mike.
Poor conditions last night with thickening fog and a bright Moon but managed to get an image and (very) low resolution spectrum. Shows the main features of a nova in its early stages…bright continuum with hydrogen emission lines. Results on my members page.
Regarding photometry…you could try a small aperture mask on you main telescope to cut the brightness. I sometimes use a 4 inch or even 2 inch on my 12inch scope for spectroscopy of bright stars for example.
Mike.
Hi Gary,
Interesting stuff. Any references to the previous outbursts available online? Curious to known if the 1927 and 1966 outbursts evolved in the same way or were they significantly different from each other?
Thanks,
Mike.
Also being observed by myself and Nick James.
Interesting passing comment in the latest ATel 13967 on the nova:
Quote: “…dust formation will almost certainly take place sometime in the next several weeks.”
So I guess a dramatic fade can be expected??? Well worth watching at every opportunity.
Mike.
A quick look at the spectrum from this morning suggests the sodium emission is much weaker now. Colour images of the dust tail certainly look less ‘orange’ which maybe why the ion tail looks much more prominent(?). I initially put all this down to the poor seeing this morning but I think it’s real.
Will post images/spectra on my members site when I’ve had a closer look. Was also imaging Gyulbudaghian’s and Borisov’s VNe last night so a lot of images to plough through!!!
Mike.
A rather poor image attached taken at 07:04UT on 23rd May. Illustrates that robotic telescopes don’t always return excellent results! However, it is good enough to show that AL Com has faded significantly, as David’s photometry indicates, and is only just visible in this three minute exposure.
Mike
Hi Stewart,
The Gemini telescope is part of the Sierra stars observatory network (SSON). Have a look at their web site at: http://sierrastars.com/ . If you want to use it you will have to set up an account and then buy some credits. Then you can schedule jobs to look at whatever you want.
A word of caution though, as with most things you usually only see the good images. There are often ‘issues’ with using remote telescopes so don’t expect perfect results every time. Prepare for some disappointments…the image I downloaded this morning was rubbish!!!
Have you looked at iTelescope? They have a wide range of telescope sizes suited to all sorts of observing projects (SSON only have two 0.5M instruments). Payment there is with a monthly subscription but you can change the amount you pay on your ‘Plan’ quite easily.
Hope that helps,
Mike.
Hi Andrew,
You are right, the May image isn’t as good as the previous two, probably due to poorer seeing conditions. That’s why my post was more of a question than a statement and I have requested more images to confirm any fading. I think the trend is real but maybe exaggerated by the image quality.
More observations welcome!!!
Mike.
For the record my image of AL Com from earlier tonight. Had to image it well before astronomical twilight as cloud was forecast to come in off the North Sea…as it did just after the image was taken. The disadvantage of imaging from sea level in Suffolk and not from a mountain in Arizona!
And a couple of questions…
1) Is there any literature out there on AL Com? A quick ‘Google’ just came up with an Astrophysical Journal article from 1992 which didn’t really say very much.
2) And are all these observations being collected together for a VSS report or similar?
Mike
I can’t really claim any credit…it’s a great telescope! The UOI 0.5M Gemini telescope is part of the Sierra Stars Observatory Network (SSON) and was upgraded last summer. The new CCD makes images like this possible. The M88/AL Com image was a single 180 seconds exposure with a luminance filter. I’m no image processing expert; I just did a log stretch and a bit of stretching using IRIS to make the galaxy look nice(!). I took the magnitude estimate from the AAVSO web site where people like Gary report all their hard work.
Anyone can sign up to SSON and buy telescope time. They also have a 0.5M at Siding Spring to cover southern objects.
Mike.
My first chance to image AL Com was on 24th April using the 0.5M University of Iowa telescope in Arizona. It had already faded to mag. 14 in the 9 days since Martin’s image.
Is anyone else continuing to monitor/image this object? I’ll aim to take some more images in the coming week…
Mike.
I managed to get a ‘quick look’ spectrum last night as the clouds parted and before the nova went behind a tree!
I used my 4.5 inch F/5 Newtonian with a 12 degree objective prism to image a 2.5 x 1.3 degree field containing the nova. It stands out clearly from the other stars in the field. Even with my un-modified Canon 550D DSLR the red H alpha emission is clear and explains the red colour of the nova seen in other images.
The bright star at top right is mag. 5.6 SAO39688, spectral type A0, showing H beta and H gamma lines.
NLC display also well seen from Ipswich. I took a few shots with a hand held camera from an upstairs window!
This one was taken at approx. 3.45BST
Hi Andy,
Thanks for your comments. I’m learning Visual Spec as we speak! It’s good because it does the non-linear calibration of wavelength which is required when working with a prism.
Not sure I can make the Spectroscopy workshop in October…but hopefully there will be a DVD of the event…???
All the best, Mike
I thought it would be interesting to compare spectra of chi Cygni and mu cephei as they are both famous red stars.
I used the on loan BAA objective prism on my 12inch F/6.8 astrograph stopped to 4 inches and an un-modified Canon 550 DSLR. Despite the limited spectral range of the DSLR the spectra are clearly quite different. Comparison spectra are on the Orwell Astronomical Society forum:
http://forum.oasi.org.uk/download/file.php?id=393&mode=view
Only a quick look at this stage, I hope to get a CCD spectrum with the same set up in the next few weeks.
I also observed visually and chi Cygni was clearly visible to the naked eye. And through my 4 inch F/5 guide scope mu Cephei appeared to be redder than chi Cygni.
Mike.
My latest image of this southern variable nebula came through on Friday. When I compared it to one taken just 23 days earlier it was clear that there had been some small changes in the nebula. I re-processed both sets of images in the same way and then compared them side-by-side. The negative images below show the changes.
The central region has brightened but the small knots of nebulosity extending eastwards have faded. A bigger version is on the Orwell AS web forum: http://forum.oasi.org.uk/viewtopic.php?f=6&t=43
This object is certainly well worth observing regularly to monitor its long term behaviour.
Mike.
