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Thanks Tim for highlighting these.
Of course ‘Britastra’ is named for the BAA and so it would be especially poetic if the weather cooperated and lots of timing chords were achieved.
Unfortunately am away in France for that event but will hopefully have returned in time for the second one.
I suspect that this could be much larger than depicted on the supplied map and that observers much further afield should try to observe this very bright star disappear momentarily (for up to 2 seconds). Asteroid occultations of ‘naked-eye’ stars visible from the UK are extremely rare and so, if clear, I recommend observers trying for this. Use optical aid, or better still video recording, together with as large an aperture telescope or other optical aid as is convenient. Naturally timing the disappearance and reappearance would be good, and do remember that the asteroid may actually be multiple (we do not know this however) and so watch out for the star to potentially disappear TWICE – you never know.
Andrew – I’ve just sent an e-mail to see if your request can be acted upon.
Presume your preferred name as displayed to members is “Andrew Thomas”.
Best regards,
Richard Miles
Hi Doug – Very pleased to hear that your library group is interested in getting involved in using telescopes on the Las Cumbres Observatory (LCO) network. There is a BAA Robotic Telescope Project that looks to encourage amateurs to pursue observing projects on remote scopes, so if you are seriously interested then there are lots of potential targets (comets and asteroids are usually very fruitful) – in some ways, the main difficulty is in deciding what is a worthwhile target to go after. Ask the Perton folk where their interests lie and let us know. We are currently setting up a small panel under the auspices of the BAA RTP to provide guidance of this kind.
Chat again soon,
Richard Miles
Thanks Nick – Looking at its trajectory, I doubt that it is visible because of a bright outburst, rather it looks that it could have been discovered by an amateur survey in the morning sky when at a solar elongation of about 70 degrees and visible from the southern hemisphere – that would have been during the previous dark lunation, several weeks before its actual discovery by the ASASSN team.
I also see there may be some issue about the poorly chosen acronym, ASASSN, when it comes to the MPC/CBAT ascribing a discoverer’s name to this comet. No name has yet been issued. ATEL #10597 describes this object as Comet ASASSN1, which in my book is incorrect. The survey that discovered it refer to themselves as ASAS-SN so it should be Comet C/2017 O1 (ASAS-SN) – the IAU stoppeda while ago adding numbers following the name.
Nick – Thanks for getting these online so promptly. Much appreciated.
Martin – Great stuff. Having the full story of the Comet Panther near-miss on your part further to what you wrote in your excellent book, “Hunting and Imaging Comets” is very useful. So, thanks for responding. For a second I wondered if I was mistaken in my assertion.
Thanks David, and Nick for posting the video from the March 29th meeting that I was unable to attend – so being able to watch the recording was great. The sound and vision quality were very good – comments from the audience occasionally breaking through into the audio. With YouTube it is possible to switch on auto-generated subtitles, which might help non-native English speakers from around the world. Good to see the report of Peter Birtwhistle’s latest achievement too as well as Tony Angel’s comet observations. Well done everyone. Richard
Hi Paul, Peter and Andy,
Trappist-1 and its system of at least 7 planets is fascinating. Yesterday we held our second BAA/UCL exoplanet workshop in London and I finished the day able to read Gillon et al.’s 2017 paper in the journal Nature on the subject. Shame that I am away in Australia and so not able to attend Winchester Weekend.
I think I may have seen Didier Queloz in 1991 when I participated in a French-language workshop at Haute Provence Observatory – I was working in France at that time. The astronomers had plans to build a new high-res spectrometer for the telescope there with a view to detect planets by the radial velocity method: this led to the ELODIE spectrometer in 1993. People thought that they were ambitious at that time. Michel Mayor was also involved and Andre Baranne was the main protagonist at OHP.
As to the question of liquid water: despite not yet measuring its presence directly, we can infer it should exist on one or more of the Trappist-1 planets. H2O is a very common constituent in the universe and almost certainly should exist as a liquid somewhere on one or more of its planets!
Cheers, Richard
Sorry to hear that, Keith. I haven’t had the problem myself but I know that the vestibular system can be affected by viruses, etc but it eventually sorts itself out. Hopefully that will happen soon in your case.
Visual observing is great to do – I was round at a friend’s last night eyeballing the Trapezium in the Orion Nebula last night for instance – but do consider not just imaging with a camera, but also taking quality monochrome images of stuff like comets, asteroids, or variable stars. Generally speaking you need an astronomical CCD camera and a photometric V hfilter for asteroids or variables, or a Cousins Rc filter or Sloan r’ filter for comets.
As we get older our eyesight inevitably declines in performance, whereas as time goes by the power of CCD cameras in the hands of amateurs is increasing year on year. This is partly because of the improvements in software such as Astrometrica, Canopus and MaximDL, but also because of the better star catalogues that are coming out. We are only a few years away from the completion of the Gaia mission, the data from which will further transform this type of observing by amateurs and others.
Excellent – the date is in the diary and will keep it free.
As for Gary and Winchester 2017, unfortunately I shall be in Australia during late March / April so will miss the VSS knees-up. My apologies.
Eric – Distilled water is usually difficult to come by as these days, de-ionised water is often sold (e.g. for lead-acid accumulators). If you can get it then you would only need to use ‘half a drop’ of washing up liquid, i.e. as little as possible, in say a litre of pure water. So say 1 mm cube of detergent would give 1 part in 1 million. Then there’s the problem of getting pure Cotton Wool BP to wipe the surfaces with. You would need the medical sort.
It would be good if some of this could be the basis of an article in the Observers’ Forum of the Journal, Alun. Something about the kit and a few examples of the resulting observations using your dual spectrograph. I haven’t seen anyone operating two systems in parallel before. Nice.
Nick, Re. the very bright meteor image – one way you can do photometry on the image to measure its brightness is to calibrate the degree of attenuation in the lens system of the internal reflection, which can be seen diametrically opposite a bright source across from the optical axis. See the secondary reflected image of the meteor towards the bottom of the frame. Try imaging a bright planet so you can integrate the light of the secondary image of it. Then image a starfield and calibrate the zeropoint of the direct image. You can then determine the equivalent brightness of he secondary image and therefore the attenuation factor in the lens.
Yes – when the daytime sky is really clear and blue you could even try to observe the brighter stars in a GoTo telescope but beware of getting too close to the Sun, Paul. Clear skies. Richard
For info: The email from Jeremy about the Survey reached me at 16:05 today (Feb 13).
I encourage everyone to complete it as the more that do so, the better the wishes of members can be reflected in any changes made to the Website in the near future.
Go for it!
Hi Roger – Your issue isn’t so much trying to focus but rather ‘How to obtain a flatter field?’
One explanation can be that the focal plane of your camera is not exactly orthogonal with the optical axis. That may mean that the way the camera has been attached is skewed slightly.
Got back from France at 10pm last night and woke at 4am. Sky here suffered from high misty cloud with one or two clearer patches. The cloud made the sky very bright within 10-15 degrees of the Moon. Since the main observatory is ‘hors de combat encore’, I would have had to use a tripod-mounted 4″ short-focus refractor to observe, but from experience I was convinced I would never have found the star in question. With a telescope of 10″ aperture or more, it might have been possible. Looking at the track of the shadow, the location here in Dorset would have been very close to that of Tim Haymes and David Arditti so not a great deal lost in the event. Congratulations to those two folk and to Peter Carson for their positives. Not easy!
Richard
Very good suggestion – since the light is supposed to be associated with emission then your spectrograph would be an ideal way of tackling what is supposed to be an ephemeral phenomenon that comes and goes. You’ll have to work out a good methodology of offseting to measure the sky and back again – bobbing to and fro on some time-scale to ensure changes in the Earth’s atmosphere are properly subtracted from the Venus signal. Beware of scattered light from the bright side contaminating the signal you are after. You might therefore need to also measure the bright side (with the gain turned down on your spectrograph – or by just measuring the sky north/south of the cusps to quantify this). That makes for 2 or 3 sky positions as well as the dark side of Venus herself.
Richard
These r-band data were recorded from McDonald. Not quite overlapping with your data, Nick.
