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TagsAnd Aries ASAS binoculars BRT BSM Cas comets Dra Draconis EC Pickering Edward Emerson Barnard Eric Stempels Friedrich Wilhelm Argelander Hans Bengtsson Henry Parkhurst Johan Kärnfelt Johan Warell Joseph Baxendell lightcurves Miras novae Otero R Ari RCB R Dra remote telescopes Robert Wahlström Robin Andersson SAAF Sebastian Otero semiregulars SRD sun sunspots SU Tau SVO T.H. Astbury Thomas Karlsson Tomas Wikander V370 And V538 Cas V2331 Cyg variable stars W Aur
R CrB has been on a plateau during some time, hovering 1.5-2 magnitudes below the normal maximum magnitude. But recently an upward trend has been visible; last night I observed it at 7.2.
The current minimum must be one of the longest in recorded history.
The Swedish Allsky Meteor Network tracked a bolide on November 28, 2016 that could possibly have produced a fall. Calculations by Eric Stempels, coordinator of the network, gave coordinates on the ground, should the bright meteor have produced meteorites.
On the initiative of Johan Warell, leader of the Solar System Section of SAAF, a meteorite search was organised during the spring. We didn’t find a meteorite, but still it was good fun trying!
Last weekend SAAF, the Swedish Association of Amateur Astronomers, met in Beddingestrand, for a couple of days of talks, observing &c. Great meeting old and new friends!
50 neglected miras is the theme for a programme run by SAAF/V, the variable star section of SAAF since February 2012. We have, at the time of writing, amassed 8826 observations, observations have been analysed and new knowledge has emerged from these observations. A number of objects in the programme has been updated in the VSX, and we are working on a paper manuscript on the observations. It has been a very rewarding experience to work in this programme, acquiring knowledge and an understanding of these objects that in many cases were discovered to be variable stars in photographic surveys 50-75 years ago but then more or less neglected, besides making several discoveries “on the side” about objects in the vicinty of the miras.
After that, we’ve began another programme on yet another group of neglected miras, this time 25 of them. It will be interesting to see these objects come into light as we observe them.
I just observed the Sun: no sunspots, just like the other day. The current sunspot cycle has been quite low.
Since a number of years, I am reporting my sunspot observations to the international data centre in Brussels; monitoring such dynamic celestial phenomena is very meaningful, I think.
The current R Dra maximum was, as noted earlier, comparatively bright. My brightest observation was at 6.2 on December 13. Here are the latest six maxima as reported by Swedish observers:
R Draconis is heading for a comparatively bright maximum. I observed it at 6.4 this evening. Yet another example of the personality of miras that makes them, even the brighter ones, such interesting phenomena to follow.
We had a great meeting in Gothenburg with the variable star group SAAF/V, our third spring meeting in four years, so it is becoming something of a tradition. Here are some pictures:
Paradoxically as it may sound, I find observing the sun these days very exciting. Few sunspots show up – today’s lunch-break observation with the 90mm Maksutov showed 3 groups and 6 spots – and the maximum last year of solar cycle 24 was very weak. It seems to be one of the weakest cycles since regular observations commenced in the mid-18th century, but by no means is it the weakest cycle sunspot-wise.
So even though there are not much action on the solar disc these days, being there to observe this feeble solar activity is very interesting and it feels meaningful to be one of stations of the network of observers reporting data to the international sunspots data centre. On any given day these at the moment, we are about 25 stations reporting observations, so it really feels that one is making a contribution to the centuries-long series of sunspot data.
Sometimes, in monitoring celestial phenomena, non-activity or low activity is also an interesting fact that would never be known had observers not been there to document it.
I observed C/2014 Q2 Lovejoy on January 14:
comp stars: 5 Tau (V= 4.1) and omi Tau (V=3.6).
The comet was a very easy catch from my urban location, one of the brightest comets I’ve ever seen.
It was a fine sight. It also got me thinking about comets of the past, and I decided to spend some time with old observing journals and other sources to try to put together a personal cometography.
I remember my first comet. I’m pretty sure it must have been comet Austin (C/1982 M1) also known as 1982G. I was 15 years old, very much interested in astronomy, and this was my first comet which made the observation memorable. Passing through Ursa Major close to Canes Venatici, it was easily seen using either the 8×40 binoculars or the homebuilt monocular concocted from a 135 mm f/2.8 photographic tele lens plus Kellner and Ramsden eyepieces I also used. I observed from under the dark skies of Anderstorp, where I was born and lived until the age of 19.
Next memorable object was comet Halley; I saw it both on the inbound leg in 1985 and in the spring of 1986. I also remember a night at the Lund Observatory station Jävan, where I manned one of the telescopes, a C14, on a Halley-themed open night at the observatory. We had long queues lining up in the cold outside the dome.
Next comes Bradfield C/1987 P1, also known as 1987s, which I observed first at 25 October 1987. By then I was a 20 year old student at the Lund University, still an amateur astronomer. It was close to the horizon, but in my 4 inch f/4 Newton I determined its magnitude to be roughly 5.8. I observed it further on on 3 November, 8 November, 18 November (tail visible).
Next came comet Liller, 1988a, observed on 11 April 1988 using my trusty old 2.4 inch refractor and my homebuilt 4 inch f/4 Newton. My old observing log book tells the tale of an almost stellar central condensation, and a straight tail about 25′. With 8×40 I estimated the magnitude to be about 6.0. I observed together with Botvid Heijel, one of my long-time friends in the local astronomy club, during a visit to my parents’ place. Just a few nights later, on the night of 14-15 April, I observed together with Anders Johannesson at the Jävan station. Liller was in Andromeda and estimated to be 6.5 using the finder of the Lund Observatory C14 (a magnificent night during which we, among other things, observed southern objects such as M83).
According to my journals, the next comet observed was 109P/Swift-Tuttle. On the evening of 30 October 1992, it was estimated to be about 7 magnitude.
This observation was made at about the same time as I drifted out of amateur astronomy. Other interests filled my days (and nights!), and this old hobby now became more and more of a memory, and my telescopes, cameras, equatorial mountings, binoculars et cetera gathered dust. I could not, of course, fail to observer C/1996 B2 Hyakutake and C/1995 O1 Hale-Bopp. Of these two, Hyakutake was the most memorable. I doubt I will ever see such a comet in my life time again, with a tail that stretched some 30-40 degrees over the firmament.
Another memorable comet during these years when I was not an amateur astronomer was discovered by myself in October 2007 (and quite a few other observers, including the British amateur Edwin Holmes back in November of 1892). I had been out shopping, and as I parked my bicycle I habitually looked up in the sky and found a bright star where none should be, in Perseus. My initial thought was that it was a nova (Perseus being in the Milky Way). I went inside, turned on the computer and soon found the Sky&Telescope story of the flare-up of comet 17P/Holmes.
Some years later, I became an amateur astronomer again. In fact, my re-entry into the world of amateur astronomy can be dated quite precisely to the evening of 25 October, 2011. It took some four months before a bright comet turned up: on March 3 2012, I observed C/2009 P1 (Garradd) at mag 7.4 using 15×70 binoculars. It was high in the sky; on March 4 it was observed at 7.3.
Next comet was 168/P Hergenrother on 6 October 2012, estimated at 9.8 (Sidgwick method) in my 20 cm Newton at 120x. It was a condensed object with an estimated coma diameter of 0.5′.On 10 October 2012 it was observed a strongly condensed object at magnitude 10.0 and a coma diameter of 1′; there was a hint of tail or at least asymmetrical coma.
Next is C/2011 L4 PanStarrs, seen as an easy object in 15×70 binoculars on April 4 2013 close to M31. I had also seen it when it was brighter and closer to the horizon. It faded rapidly, on the evening of 15-16 May I observed it at 10.0 using my 20 cm Newton at 179x. It was then in the field of RY Cep, so finding suitable comparison stars was easy.
C/2013 R1 Lovejoy was observed on 27 November 2013 estimated at 5.6 in 15x70B. A fairly condensed coma.
C/2014 E2 Jacques was a fairly easy object at magnitude 7.0 on 23 August 2014 in 15x70B, coma diameter estimated at 6′. It was also observed on 25 August (mag 7.1, DC 5, no tail) and 27 August (mag 7.1).
All in all, I have observed 14 comets visually. Not many, compared to some of my fellow amateurs. I find comet observing to be fun once in a while and I try to observe the brighter objects at least if they are well placed high up in the sky (my regular observing location is surrounded by five story buildings).