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Thanks for your report, Lars.
I had good weather and recorded the target field for 5 minutes centred on the predicted time. No occultation was detected from Leeds. I’ll put a summary report on my Member Page.
Hopefully some observers had a positive result to help define the path of the shadow zone.
Alex.
The prediction lists the target star as ‘possible double star’. Let’s hope we obtain timings and light curves of this event. Please observe even if you are 100km distant from the predicted shadow zone.
Clear skies,
Alex.
Melvyn’s family have now arranged refreshments after the funeral at Wakefield Crematorium. They have provided the following directions:-After the service, guests are invited to make their way to The Milnes Gaskell Function Room which is adjoining Howarth Funeral Services at 125 Denby Dale Road, Thornes, Wakefield WF2 8EB. Howarth Funeral Services is shown as Thornes Parish Church of Saint James on online maps, but it is the adjacent building.Parking is limited immediately outside the venue but there is parking available at the edge of the park opposite. A road off the roundabout leads up to the Premier Inn and there are a couple of small car parks on the left of the road. People will then have to cross the dual carriageway to get to the function room.Alex.Sorry Bill, I didn’t record the one at 21:30:14.
Don’t give up hope, because we have a number of video cameras monitoring southern Scotland / Borders and we might have a successful match when their clips have been checked and reported.
Clear skies,
Alex.
Hi Bill,
Very nice spectra!
I think I also recorded your Perseid on my Leeds_N camera so I’ll send you my provisional csv file for August – 1500+ meteors so far.
Clear skies,
Alex.
I fared much better than last year. I sat outside from 23:00 to 00:30 BST and noted some nice bright long-pathed Perseids in the earlier part of my watch. It was great to see a negative mag meteor streak across the sky then watch it again by replaying it on one of my adjacent UFO Capture PCs.
My provisional haul recorded by my video cameras on the night of August 12/13 was:-
Perseids
Leeds_N 123Leeds_NW 182Leeds_SE 164not including good numbers of minor shower members.I’ll put a couple of examples on my BAA Member Page.Alex.Hi Bill,
I was clouded out at that time.
Always like to see your spectral diagrams, the composite intensity plots and wavelength colour strips are a nice way to present the results.
Fingers crossed for obtaining multi-station orbital data this season.
Clear skies,
Alex.
Hi Bill,
I don’t think I’ve ever seen a meteor train distorting whilst the body was still in flight. That’s a great capture.
As discussed offline, my Leeds_N camera wasn’t active at that time. I was AWOL in Cambridge for the weekend, attending the SHA meeting. I don’t leave my indoor system running if I’m away for more than a day. If only the meteor had appeared a day earlier…
Cheers,
Alex.
Hi Denis,
I last saw Rob McNaught at an ASE meeting at Calton Hill Observatory in September 2007. Here’s a pic of him and Dave Gavine taken in the Observatory’s reading room.
You could ask Dave if he’s still in touch with Rob.
Clear skies,
Alex.
Clear blue sky all day in Leeds, so one consideration was trying not to get sunburnt.
I monitored the transit (with my 102mm apo refractor and QHY mono camera) from before first contact up to shortly after 7pm when local rooftops intervened, then quickly transferred to an 80mm refractor set up near the front of the house to follow the last phases. Mercury looked like a tiny ball-bearing in silhouette against the Sun. Seeing wasn’t very good and it was tricky to achieve good focus.
The resident blackbirds weren’t happy that my presence was stopping them from accessing the birdbath, and some wasps took a long-term interest in my laptop computer.
The sunny weather brought back happy memories of observing the 2004 transit of Venus from Cyprus – and as I did on that occasion, had a beer at mid-event.
Cheers,
Alex.
Thanks Jeremy.
I’ve observed a few Aldebaran occultations over the years, with varying success. On 1979 Jan 9 I observed and timed a DD and RB pair, using a stopwatch and time signals. Modern video systems and techniques allow us to obtain much smaller O-Cs than in the days of manual timings, personal equation, etc.
Clear skies for 2016.
Alex.
In recent weeks the weather has been cloudy, cloudy with rain, or clearing and blowing a hooley, so it was a pleasant surprise to have a fairly clear sky and occasional light breeze for recording and timing the D and R events.
Clear skies,
Alex.
Hi David,
There’s some discussions in past Journals of Scaliger’s work, as documented in the BAA Journal DVD Archive.
JBAA vol 57 no 3 (1947 March) has a paper by A. K. Bennett on ‘Scaliger J. J. 1540-1609’, but it may not answer your questions.
Best regards,
Alex.
Hi Bill,
There will be some uncertainty in the result from Analyser if its profile was created from a small number of reference stars.
Analyser sometimes categorises a meteor as a sporadic (or other shower membership), giving an unexpected result. Two reasons for this can be the meteor’s angular velocity and its distance from the radiants stored in its internal catalogue. The meteor’s estimated velocity is an important factor and if this falls outside the expected ranges (for each known shower) it can fail the shower membership tests and be categorised as a sporadic.
Have a look in the UFO Analyser Uty tab and tick the ‘analyzelog’ box. This creates a txt file when analysing a meteor clip. The file contains details about the reference stars, the meteor’s angular velocity and how well it matches against currently active slowers.
Clear skies,
Alex.
Hi Bill,
Yes, UFO_A is normally used to process meteor captures from a wall-mounted video camera, but it can also be used to analyse meteors from a one-off tripod-mounted session.
This would help to assess whether all your spectra are from Quadrantids or if there’s any DaDs in there.
The parent body of the Quadrantids is believed to be 2003 EH1, an Amor NEO. Multi-station observations of the Quadrantids in 2014 by the NEMETODE team showed that the meteors were extinguished at higher altitudes than the Geminids, even though they have similar Vg, suggesting that Quadrantids are more fragile material.
Cheers,
Alex.
Hi Bill,
UFO Analyser can display the meteor trail against the star field, compute its probability of shower membership (from its internal catalogue) and it will measure its offset from the radiant.
This is more objective than an alignment by eye.
Clear skies,
Alex.
Hi Bill,
Here’s a plot of both radiants, from UFO Orbit.
If the December alpha Draconids are accepted as a genuine minor shower we can have cases where some of their meteors are mis-identified as Quadrantids, and vice versa.
Clear skies,
Alex.
Hi Bill,
As discussed offline, the meteor shower data are suppiled in the ULE_J5.csv and ULE_J6.csv files bundled with the UFO software suite.
They are also listed in the IAU MDC
The Vg of the two showers are essentially the same, 41.36km/s (Quads) and 41.6 (DaDs).
UFO Analyser derives an estimate of the meteor’s velocity from a single-station recording, then UFO Orbit computes an estimate of its geocentric velocity using data from two or more stations.
Cheers,
Alex.
Hi Bill,
Fascinating stuff.
You also have additional camera alignment options with David Anderson and Denis Buczynski.
I recorded 103 Quadrantids on Jan 3/4, but in addition there were 18 meteors that UFO Analyser categorised as J5_daD (December alpha Draconids). This shower has been confirmed by SonotaCo data, but its radiant lies close to that of the Quadrantids, being active at a similar time of year and with similar Vg.I always regard shower membership from single-station work as provisional. A single-station meteor could be assigned J5_daD membership, then later identified as a Quadrantid from dual- or multi-station analysis.Is it possible that you have a mixture of Quadrantid and December alpha Draconid spectra?Cheers,Alex.
