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David,
thanks for posting about this brief opportunity to see this NEO from the UK.
I find it frustrating and amusing in equal measure that the MPC’s ‘Daily Minor Planet’ often tells us about NEO flybys the day after they’ve been and gone. 🙂
I had to smile this teatime as I checked my e-mails and ESA’s 2010 WC9 Close-Approach Fact Sheet arrived in my Inbox at 16:09. Informative but no use for planning a UK observing session.
Thankfully other resources such as the Minor Planet Mailing List and some astro magazines tell us in advance. I recorded 2010 WC9 last night and will add something to my Member Page this evening.
Clear skies,
Alex.
Hi,
It looks like my NW camera recorded the same event, although the meteor was near the edge of my FoV, so unfortunately I only recorded one of the trails.
Cheers,
Alex.
We’re all likely to produce unintentional typos after a long observing session!
I used my Watec video camera and 50mm f/1.7 Vivitar SLR lens to record the field of V392 Per. I’ll add a pic to my Member Page later this weekend.
Come along to Newcastle tomorrow. My talk won’t be flawless but I hope there’s something in there of interest. 🙂
Alex.
On Denis’ Member Page entry for May 2 a typo describes V 392 Per as a ‘comet’, so keep observing! 🙂
Clear skies,
Alex.
Hi Ian,
Many thanks for expressing an interest in these items. My message was posted last year and I should have updated it because all the Journals and Handbooks have now found good homes, such as with the BAA Archivists.
I noted in the For Sale column in the 2018 February Journal there is a set of Handbooks on offer.
Alternatively, as a BAA member you can download PDF versions of the Handbooks and Journals via the Publications – Downloads tabs on the BAA website. Another option would be to purchase the BAA Journal Archive on DVD from the BAA Shop.
Clear skies,
Alex.
…and this 6th mag ‘nova’ was a ghost image of Aldebaran…
http://www.astronomerstelegram.org/?read=4513
Clear skies,
Alex.
Jeremy, in due course all contributing observers should receive a copy of the Lucky Star team’s paper, perhaps a preprint. Depending on where it’s published we’ll have to see if general readers have to negotiate a paywall, although the key results should wend their way into the public domain.
Ray, I’m just summarising the results of many observers. The real science will come from the work of Bruno’s team, hopefully revealing any changes in Triton’s atmosphere since 1989.
Cheers,
Alex.
Most observers of this asteroidal occultation have now reported their timings and the asteroid’s profile (derived from multiple chords) has been updated on Euraster (maintained by Eric Frappa). There’s still one or two reports to come in. There looks to be some discrepancies in the set of chords.
I’ll add the shape profile link to the observation on my member’s page.
Clear skies,
Alex.
Hi Dominic,
The video camera will output 25 interlaced frames per second (PAL) and the VTI timestamps each video field, 50 per second. Many occultation (and meteor observers) record to AVI files using a USB video grabber. Limovie and Tangra can read and analyse these at the deinterlaced field level. We use this to get good time resolution (0.02s) on lunar occultations and bright asteroidal events…
https://www.britastro.org/node/8992
The pairs of video fields from an integrating video camera will give (almost) identical images.
UFO Analyser processes meteor AVIs at field level to estimate the meteor’s velocity.
Cheers,
Alex.
Hi Tom,
If you are timing lunar impact flashes I guess a timing accuracy of only 0.1s is required to confirm a simultaneous event but researchers may prefer to 0.01s for light curve analysis.
Analogue video at 50 fields per second gives exposures of 0.02s per field, which is the fastest rate currently used by most occultation observers. All these GPS-linked VTIs have an accuracy of 1 – 100 microseconds.
For more information on VTIs and video camera timing delays (internal delays and integration effects) have a look at the work of Gerhard Dangl (AT) here.
Cheers,
Alex.
Hi Tom,
Wojciech Burzyński (PL) gave a talk on this at last year’s ESOP in Freiberg. The PDF of his presentation can be found here.
Using a 1PPS GPS receiver module they found that their Arduino-based VTI gave timing accuracies as good as the off-the-shelf IOTA-VTI and GPSBOXSPRITE2 models used by many occultation observers around the world.
Happy assembly!
Alex.
Hi Tony,
I have never seen a copy with the set of negative prints. When I visited Skalnate Pleso we were shown their collection of Becvar atlases and catalogues, so I might have been shown a special edition like yours, but I don’t recall it.
Len, the Stara Lesna ESOP was in 2007. As you know I was in Wakefield yesterday, assessing the extent of Melvyn’s collection of star atlas and catalogues. It includes Atlas Coeli and its Catalogue, so we can set them aside for you if you wish. Melvyn’s atlases have a personal touch because some pages contain his pencil sketches of the tracks of comets that he observed.
Clear skies,
Alex.
Hi Bill,
Here’s some plots from NEMETODE data showing the detection and extinction altitudes of the meteor family. The geocentric velocity of each meteor shower is indicated by Vg.
I’ll be updating these plots in the New Year with data from 2016-2017.
Clear skies,
Alex.
Hi Bill,
The analysis gave the meteor an apparent magnitude of -1.5, as seen from my location. A meteor’s absolute magnitude is its estimated magnitude had it been in the observer’s / camera’s zenith at an altitude of 100 km. This meteor could easily have appeared brighter from your station.
It can be challenging to record meteors with a DSLR. Lens effective aperture and ISO setting are big factors. I have an example of a bright Perseid that was spectacular on my video camera but a much more feeble streak on my DSLR image.
Clear skies,
Alex.
Hi Bill,
I think you can conclusively claim this to be a Leonid meteor spectrum.
The attached composite image was captured by my indoor Leeds_N camera, a mag -1.5 Leonid, confirmed by UFO Analyser. The meteor was recorded as it flashed into the RHS of the field of view. The brighter upper trail is the Leonid, the fainter lower trail is an artefact of the double glazing.
Cheers,
Alex.
Hi Bill,
just checked my Leeds_N camera. A fairly clear sky from here but I didn’t get your listed meteors. Perhaps David A or Denis B might have them.
Cheers,
Alex.
Oops, I was going to attach an occultation report form template, but the website doesn’t support uploading txt files.
Clear skies,
Alex.
Hi Richard, William,
Thanks for your confirmations of a miss from you locations..
Tim and I haven’t received a positive report, yet. The hunt is still on for the shadow track!
Clear skies,
Alex.
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.
