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Fireball Reports 2011 July to December

(This report has been compiled from SPA Forum entries posted by Alastair McBeath).
 
July
 
* July 1-2, around 23:00 UT, a fireball-class meteor spotted from Staffordshire. 
 
* July 7-8 produced one bright, fragmenting fireball at 22:58 UT for an observer in Midlothian, followed by a magnitude -5, very slow, yellow event from Stirlingshire around 23:25 UT. The latter may have produced a sudden sound almost immediately after it vanished. 
 
* July 11-12, at 21:22 UT saw a magnitude at least -5 meteor seen from indoors in Suffolk. This may have had a simultaneous rumbling sound associated with it. 
 
* On July 14-15, an event at 01:58 UT was reported by five observers spread across Hertfordshire, London and West Sussex on land, plus a ship off the Needles in the western Solent, off the Isle of Wight. The meteor was of at least magnitude -3, and may have been significantly brighter for those nearer the trail.
Most sightings of it came from a Stargazers' Lounge chatroom topic, at: 
http://stargazerslounge.com/observing-widefield-special-events-comets/148915-earth-grazing-meteor-02-58am-14-07-2011-a.html#post1883030
 
Regrettably, very few people were able to give accurate sky-positions for the event, and most seemed to have missed the end of the flight anyway, as it passed behind near-horizon obstructions or clouds. By assuming typical meteoric heights, a start at around 90-110 km altitude could have seen the flight begin over the SW Netherlands, from where it may have flown on a generally NE to SW path, initially along or near the Belgian and French coasts to about Boulogne, before cutting across the Channel heading towards the NE Cotentin Peninsula. Where the object ended was unclear, as already indicated, but perhaps over or west to southwest of that Peninsula. This is only a best guess, however. 
 
An average of the estimates suggested the fireball's flight lasted about 6 or 7 seconds, with one witness indicating it had had a distinct green colour. If the possible atmospheric path proposed above was right, it would have been roughly 500 km long and thus the object would have had an atmospheric velocity, not allowing for deceleration, in excess of 60 km/sec, so very fast meteorically-speaking, not very slow as I'd earlier thought. 
 
* July 17-18, about 03:35 UT, brought a very bright, very slow, yellow meteor for a fortunate car-bound group of witnesses in Hampshire. 
 
* July 18-19, at 03:21 UT, a brilliant green fireball was spotted by two people in different parts of Banbury, Oxfordshire. 
 
* July 28-29 provided another doubly-witnessed fireball at ~21:16 UT, this time with the observers at separate locations in Wiltshire and Hertfordshire. This meteor was brighter than magnitude -5/-6 and slow-moving. Although no detailed triangulation was possible from the data provided, it is probable the object flew on a direction between east-west to southeast-northwest above the Channel, possibly ending over or near SW England to S Wales. 
 
* Later on July 28-29, at 00:45 UT, another bright meteor was spotted from County Fermanagh. 
 
August
 
* Around 21:30 UT on August 3-4 , a bright, blue-green event was seen from Berkshire.
 
* This was followed at 22:05 UT on August 3-4 by a fireball imaged by all-sky cameras operated by old Meteor Section friend Klaas Jobse at Oostkapelle in the southwest Netherlands:
http://cyclops.klaasjobse.nl/jcms/showpic.php?img=1528_20110803_2205UT_Oostkapelle_w700h716.jpg
and the University of Hertfordshire at Bayfordbury, Herts:
http://star.herts.ac.uk/allsky/imageget.php?jde=2455777.42045&c=1
 
This  seems to have also been seen by two lucky visual observers as well. SPA Vice-President Robin Scagell kindly forwarded these reports, both made from western London.
 
As the meteor chanced to lie on a trajectory angled roughly in-line with the view from both stations towards one another, it has been impossible to accurately estimate its atmospheric path, regrettably. However, it may have been moving roughly between south-north to southeast-northwest over part of southern East Anglia or the adjacent North Sea. Heights for the start and end may have been of the order of 100 and 30 km respectively, as a best-estimate, though this is far from certain. Grateful thanks go to David Entwistle for spotting this pair of reports on the websites noted above.
 
* Near 22:45 UT on August 3-4, a very bright meteor was spotted from Buckinghamshire, which witness was then doubly lucky in spotting a further magnitude -9, blue-white, meteor around 23:00 UT.
 
* Two events were spotted on August 16-17. The first was around 21:55 UT, possibly a post-peak Perseid, as it left a persistent train after its brightest flare (magnitude uncertain), while dropping below Cassiopeia, as seen from North Tyneside.
 
* The second August 16-17 fireball was almost exactly four hours later, at about 01:55 UT. This was a magnitude -4 meteor, which ended in clouds as seen from South Ayrshire.
 
* August 21-22 produced another multiply-observed fireball, at 20:45 UT or so, a magnitude -3/-4 meteor, possibly brighter, that was seen from nine locations across southern England. Some reports of it can be found on the SPA's Observing Forum, here: http://www.popastro.com/phpBB2/viewtopic.php?t=15934
 
Observations came from Herefordshire, Worcestershire, the West Midlands, Essex, London, Wiltshire and Hampshire. Unfortunately, few positional details were secured on just where the meteor had happened in the witnesses' skies, but the fireball may have been moving somewhere between SE-NW to S-N over SW England to SW or mid-W Wales, or the seas nearby, as a best estimate. The colours noted in the meteor's head were equally split between the observers, as either white, yellow or orange, or a mix of two of these. Estimates for the object's visible duration averaged just over five seconds.
 
September
 
* September 4-5, around 20:00 UT, provided a bright fireball for a witness in East Sussex. 
 
* The evening twilight on September 13-14 yielded a magnitude perhaps -12 event, as seen from Suffolk, at about 19:00 UT. 
 
* From September 17-18, Assistant Meteor Director Tony Markham forwarded details that an extremely bright, flaring meteor may have been automatically imaged from Essex at 21:32 UT by Peter Meadows. See: http://www.petermeadows.com/meteor
for the photo. Unfortunately, as the object wasn't witnessed separately, we can't be sure it was definitely a fireball (it may have been an aircraft or a sky-lantern, though it probably wasn't a satellite, as its path was likely too long for the ten-second exposure). Part of the trail is on the adjacent ten-second image, which would not rule out its having been a meteor, if it appeared right at the end of one shot, and was slow-moving enough to be still in-flight by the start of the next, but does somewhat count against it. The obvious brilliance of the object means it could have been widely-observed if it was meteoric, so any confirmatory data would be particularly helpful! 
 
* Two reports have arrived of a magnitude -5/-6 or brighter fireball on September 27-28, at 23:25 UT, one from South Yorkshire, the other Co Londonderry. Early indications are this meteor may have been high above NW England to southern Scotland, or the nearby Irish Sea.
 
October
 
Note that identified Draconid and Orionid fireballs near their respective maxima on October 8 and around the 21st are not included here. 
 
* October 22-23 brought a magnitude -4 event at 17:28 UT for a lucky witness in Hertfordshire at a public star-party. Sadly, nobody else there was looking in the right place at the key moment. 
 
* Around 06:00 UT on October 23-24, a bright fireball was reported from London. 
 
* Two sightings of another bright fireball were received from later on October 23-24, each timed to within a minute of 18:41 UT, from London and Hove. A short note featuring one can be found on the SPA's Observing Forum at: 
http://www.popastro.com/phpBB2/viewtopic.php?t=16268
 
November
 
November's weather was typically poor across the British Isles, judging by the comments and general lack of observations received by the Meteor Section. However, three fireballs have been reported from the second half of the month recently. 
 
* At 18:32 UT on November 22-23, a magnitude -4 or so meteor was spotted by a driver in Oxfordshire; 
 
* At 19:58 UT on November 22-23, a similarly bright object, probably peaking in the magnitude range -3 to -5, was seen from Buckinghamshire. 
 
* At 03:52 UT on November 25-26, a meteor of probably magnitude -4 or more was imaged by an automated video camera in East Sussex, which produced three or four flares in brightness. 
 
December
 
Fireballs, other than those seen from the Geminids near their maximum around December 14, as spotted from the British Isles and nearby during 2011 December:
 
* At 21:31 UT on December 4-5, a bright orange fireball was observed crossing the southern sky by a motorist in Herefordshire.
 
* On December 9-10, around 06:15 UT, another bright fireball was seen, from Essex.
 
The next two may have been Geminids, but there's too little information on either to tell:
 
* On December 13-14, around 21:40 UT, a bright green fireball was seen from Hertfordshire. 
 
* December 14-15, 18:22 UT brought a magnitude -6/-8 meteor for a witness in North Lincolnshire, from where the fireball was seen quite low to the north.
 
* Two reports, from Norfolk and Hertfordshire, of a bright green fireball at 19:57 UT on December 20-21 were first posted elsewhere on the Observing Forum, at: http://www.popastro.com/phpBB2/viewtopic.php?t=16516
 
* A magnitude -4 or so event on December 21-22, at 06:28 UT, seen from indoors in Suffolk.

Added by:  Tracie Heywood