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Nick,
The sequence between 20:50 and 21:10 or so is very good.
That after about 23:00 to 23:20 or so is remarkable by the overall brightness of the display at time.It was cloudy but not fully overcast here in Dorset and I saw the one around 21:00 UT lighting up the clouds with red and green.
Two spectacular displays in the one year. I’m not complaining.
With all these high-energy particles from the Sun, I am wondering if that explains why smoke alarms and the electronic door bell have been going off spontaneously. Could there be a link with this year’s aurorae?!Richard
Thanks Bill for sharing this tremendous observation. Certainly the best I’ve seen from the amateur community. I thought about comparing the spectrum with that recorded in Chile at the VLT FORS1 instrument taken in 2002 but sadly the two spectra are from different regions of the optical spectrum. So you may very well be correct that yours is the best so far obtained in that spectral range. See:
https://repository.arizona.edu/bitstream/handle/10150/656680/azu_meteoritics_v39_n4_609_616_m.pdf?sequence=1Giovanni,
Interesting two references you give. Thank you. The Mazzoleni et al. (2023) article I came across myself a week or so ago and the Voigt et al. (2024) is new to me. Although people have speculated about the link between light at night and neurodegenerative diseases in the past, it seems that in the last few years more significant findings have been appearing. Another angle is the importance of melatonin’s day-night cycle on the health of humans and other creatures and how higher levels of melatonin are protective. I often find it remarkable that evolution has taken advantage of the day-night cycle for the benefit of creatures. Darkness permits the triggering of hormones and other functions that cleanse the system ahead of a new day dawning. Inhibition of melatonin production by light occurs at very different light levels for different creatures. So in my mind, the health arguments are getting stronger in recent years and are much more credible than they were a decade or two ago.
Thanks Jeremy for clarifying the thinking behind Brad Schaefer’s predicted eruption date of 2024.4 ± 0.3 and the two refs that you pointed to – they both worked fine in the end. The pre-eruption dip looks to be a good harbinger although what happened re. its high state before and after the 1946 event does seem to assume that the object will follow a similar behaviour as last time. We shall see!
btw: Since my earlier message, I have had some useful feedback privately from Graeme Waddington about heliacal rising/setting of stars. It sets a good example of how the BAA Forum can work well.
Richard
Jeremy. In reviewing the 4 definitely observed eruptions, Brad Schaefer’s comments that the recurrence timescales are 7×81.4, 78.5, 79.7, and then states a likely 78.3 ± 0.3 yr should apply between 1946 and the next eruption. So that translates to 2024.4 ± 0.3. I don’t understand how he can ascribe such a small uncertainty (± 0.3 yr) in this prediction. Statistically from the above numbers you could envisage a distribution in which 9 eruptions span the range 77 to 85 yr, and that since the last two have been in the lower half of that distribution, the next event has more chance of being in the higher half, i.e. more like 82 ± 3 yr, which then takes it to the beginning of 2026. It does look like he has made an assumption that the periodicity is for some reason decreasing on average monotonically in a somewhat linear fashion. Is there some theoretical reason why that might be the case, I wonder?
P.S. Brad Schaefer has done all sorts of research over the years. Am putting together a paper at present that uses three references to his work from 1985, 1986 and 1987. He writes that he was the first to work on this subject since antiquity and few if any other visual observers have since investigated this topic. The references are:
Schaefer, B.E., 1985. “Predicting heliacal risings and settings”, Sky and Telescope, lxx, 261–3.
Schaefer B. E., 1986, “Atmospheric extinction effects on stellar alignments”, Archaeoastronomy (Supplement to Journal for the History of Astronomy), (10), S32–42.
Schaefer, B.E., 1987. Heliacal rise phenomena. J. Hist. Astron., 18(11), S19.A few of us had a stargazing session at the Giant viewing area in Cerne Abbas, Dorset late yesterday evening.
Early on about 10.00-11.00pm there was quite a bit of high cloud that largely dispersed by midnight.Here below are some hand-held views – one towards Giant Hill.
Brightest star is Vega in Lyra and the clouds are visible as dark silhouettes.Although am at a relatively southerly latitude compared to other UK observers, at one point the aurora was visible above the southern horizon.
You can see the parallelogram-shaped constellation of Corvus the Crow at a declination of -20° low down in the last two shots, where the brightest star is Spica.Attachments:
Thanks Howard. The claimed mechanism affecting chance of stroke to quote is: “Continuous exposure to artificial light at night can suppress production of melatonin, a hormone that promotes sleep. People with poor sleep, compared to good sleepers, are more likely to experience worse cardiovascular health over time”.
Am not sure the researchers have been able to prove a causative link. Their argument is a multi-step one with some doubt that one can link each of the steps directly. People who are exposed to a lot more light at night are leading a very different lifestyle to someone who lives the saying, “Early to bed, early to rise makes you healthy, wealthy…”
Richard
Thanks Pauline for making these pictures of the 2016 50th WW available.
I attended that particular extravaganza on that occasion.
Downloaded a few choice photos: one of Bob Mizon, Alan and John Mason wearing what??, group photo, that one of you, telescope and George Sallit, etc.
Yep – a few memories indeed!Matt,
Well then where do I start??
I met Prof. Brian Cox at a BBC event in London to celebrate 55 years of The Sky at Night and strangely enough I mentioned to him that my school prize in 1963 was The Observers Book of Astronomy, which I read from cover to cover during a train journey heading off on holiday that year. He of course mentioned his encounter with ‘TOBOA’ which might also have been in 1971 like you. So you, me and Brian C. have that one thing in common!I cut a lot of the colour plates out of TOBOA (together with some from the non-PC “Boys Book of Astronomy” by Patrick) and stuck them on the front cover of my school scrapbook, which I carried around with me to the various lessons. I still have it somewhere ….
Thanks Wayne – I saw your latest note on ARPS’ groups.io
This asteroid is well placed for evening sky observation so we should keep observations going over the next month or two at least.Richard
Thanks Wayne for flagging this need.
A few questions – given we are December 12, can you indicate at what Phase value that corresponds with for the two possibilities?
Another is the magnitude system used. The plot does not show this. I imagine it is either V, R or G?
Cheers,
RichardPaul, That ‘node/12028’ link took me to: ‘https://britastro.org/2018/finding-the-way-part-1’. Is their a typo in your last note of October 10?
RichardRead all of the article – fascinating accounts of the life of these two ladies. Well done to you and to the Historical Section. The article also helps keep the BAA’s name in the public eye and helps our mandate to highlight the roles of women in astronomy, hopefully encouraging others to sign up as members of the Association.
Good to have the two Paul’s potted descriptions of facets of cosmology. Makes for a nice read on a Saturday evening!
Richard
Thanks Tim.
I have updated our MISSION 29P News page to illustrate what was found. See:
https://britastro.org/section_information_/comet-section-overview/mission-29p-2/mission-29p-centaur-comet-observing-campaignRichard
David – What a tale! – I know that windy road well but had not realised that you and Bob were joint partners in crime over there. very nice. If only Bob were here to give his side of the story!
Thanks Howard, David, Paul, etc. on recollections of Bob.
Whenever local lighting issues came up, Bob was always the person we relied on for guidance and wisdom.
I feel that the UK and anyone with aspirations to improve the lot for nature and dark skies have lost one of the country’s leading ambassadors for dark skies.
Who amongst the younger folk will pick up the baton and run with it like Bob has done these past 30+ years?All the talk of saving the environment and that’s what it usually seems to be just talk.
People action’s tend to obey some other law, by which they see little if any obligation to change what they do themselves that may have a bearing on societal aspirations. Or in many cases people know not what they do!Are young people in schools made aware of this issue by their teachers, I wonder?
I’ve seen this:
https://greenspacedarkskies.uk/learning/
