Is it a plane? Is it aliens? No, its a meteor, as caught by SCAMP and FRIPON

From an original article By Jim Rowe
With updates by Mark McIntyre

At 5:51 on the morning of Sunday 8th September a very bright, slow meteor was spotted from southern England and France.

Or a plane crash, as it was initially reported – it caused quite a stir in both the press and on social media. It was caught on camera by SCAMP in Honiton (part of the FRIPON network) and by several UKMON and BOAM cameras in England and France respectively.

This image was taken from Hampshire by Steve Bosley of UKMON.

 

Most newspaper websites picked the story up promptly, with the notable exception of the Daily Star, which therefore missed an opportunity to use the words “UFO” and “Alien” in a meteor report.  Full marks go to “The Sun” for its infographic which is pretty close to being right. Less full marks to the BBC for their lead image below, which seems to be a contrail left by the plane that the meteor wasn’t. Oops. Thanks also go to Richard Kacerek of UKMON who helped the press get the story right.

 

As mentioned earlier, the meteor was initially misreported by the public as a potential plane crash, leading to police helicopters being scrambled to search for survivors. Fortunately this misunderstanding was soon cleared up.

So what actually happened?

A meteor entered our atmosphere with a very shallow trajectory and left a long trail. It took as much as 30 seconds to cross the sky – meteors normally burn up much more quickly because they come in more steeply.  The meteor was caught by twelve FRIPON cameras in France and the SCAMP camera in Honiton, Devon. These are shown in shown in green on the map to the left.

 

From the UK it appeared very low in the south but was seen by many members of the public. Here’s a composite image of the meteor from the Honiton SCAMP camera. It’s the white streak at the top right of the image – very distant, and so very low on the horizon.

 

 

 

Science!

Firstly FRIPON was able to calculate the meteor’s velocity curve. When first visible the object was almost 80km up and travelling around 15-16 km/s. About 28 seconds later it was 40km up and had slowed to about 7-8 km/s, but in that time had travelled around 380km across the Noth Sea, France and the Atlantic. It seems to have been on a very shallow trajectory, but too slow to escape Earth’s gravity and escape back into space.

 

FRIPON also calculated the trajectory, shown here as the black line. The ground track (the imaginary line on the ground exactly below the meteor) is the line at the bottom of the wedge. The Sun picked up a version of this image but then reported that the meteor crossed England’s south coast, which is incorrect.  In fact if it didn’t burn up entirely, then the meteor landed somewhere in the Atlantic.

Other data from UKMON suggests that the meteor was at least magnitude -4 and was a sporadic, meaning that it wasn’t part of any known meteor shower.

And finally here’s where FRIPON think it came from. The orbits of Mercury, Venus, Earth and Mars are shown as red rings (Mars is the dotted one) and the object’s orbit is the black ellipse. It seems to have been a chunk of asteroid that orbited mainly between Earth’s orbit and that of Mars, but crossed the orbits of both. This time, it didn’t make it past the Earth.

 

 

 

Of course, this is just the sort of rock that we’d love to recover for the Natural History Museum. But sadly this one, like the last few, is somewhere at the bottom of the Atlantic – safe in Davy Jones’s locker!

Hopefully next time we’ll have one land on land…

About SCAMP

SCAMP (the System for Capture of Asteroid and Meteorite Paths) is a network of all-sky cameras based in the UK.  SCAMP detects and records bright fireballs so that the location of any resulting meteorite fall can be estimated.  Any meteorites recovered using SCAMP will be donated to UK museums or universities, along with all images and data recorded.

For more information on SCAMP see www.scamp.org.uk.  To receive alerts from SCAMP you can sign up here.

SCAMP is fully integrated with the French FRIPON network of about 100 cameras.  For more information on FRIPON see www.fripon.org. For a daily e-mail summary of all FRIPON multi-station fireball captures (including SCAMP captures), click here to subscribe or send an email to newsletter-request@fripon.org with “Subscribe” as the subject.

Bright Fireball over the UK!

At 03.52 on the 30th of March 2019 a very bright fireball was detected by a number of observers around the UK. As well as visual observations, the fireball was picked up by multiple stations in the UKMON & NEMETODE networks and by the newly-installed Scamp system. The video below shows the view from one of my meteor cameras in Oxfordshire.

Scientific Analysis

Multiple detections enabled quite detailed analysis of the object. William Stewart of NEMETODE calculated that the object weighed between 190 and 330g, was of asteroidal origin and was between 36 and 60mm in size. The flight path and the meteoroid’s original orbit were also calculated (see below).

This is a great example of the real science that can be done with meteors, and of great collaboration between UKMON, NEMETODE and Scamp to help generate that science.

Now, if only one of these would fall over land….

Mark McIntyre, Meteor Section Director

Data collected by Nick James, Jim Rowe, William Stewart, Mark McIntyre and others.

Fireball reports from 2012 April to July

The lighter evenings and shorter nights of late spring and early summer inevitably lead to a reduction in the number of fireballs being seen. This also makes it more likely that a fireball will only be reported by a single observer and hence it is often not possible to confirm whether an object was definitely a fireball or just a local event, such as a sky lantern.

The following reports have been received :

Sam Mundell (Gosport, Hants) reported seeing a mag -3 fireball at 2058UT on April 21, travelling from Ursa Major towards Cassiopeia and lasting for 5 seconds.

Peter Meadow (Great Baddow, Essex) imaged this Lyrid fireball (below) at 01:55 UT on April 22. It has a short path because it is almost head on from the observing site. The second set of images show the decay of its persistent train.

Peter Grego (St Dennis, Cornwall) imaged a fireball at 0229UT on May 13. He described it as “very slow, flaring and fragmenting mid-flight, 20 degrees alt and almost parallel with horizon, appeared in southeast, brightened, visible in flight for seven or eight seconds, brilliant white head with orange-yellow trail about ten degrees long, trail not persistent. Terminated due east. Magnitude -5 at brightest.”

Katie Sludden (Comrie Forest, Perthshire) saw a fireball descending in the ENE at 2257UT on May 15, including the description “It burned with a slight green haze and left a bright white trail in the sky. It lasted up to 3 seconds but I think I only caught the end of it.”

Nick Wright (Roundswell, Devon) saw a fireball of duration 5 seconds, possible of mag -10, at 0130UT on May 26 low in his western sky. His description included “Trail was very clear, straight and white. The explosion at the end of the flight was very bright and instantaneous”

Melanie Dunkley (Ely, Cambs) saw a fireball at 2325UT on June 15, describing it as “Started as what I thought was a shooting star but then the orange tail appeared which was pretty long.  This tail disappeared and the white became brigher and also looked green until it vanished. The entire show lasted probably between five and ten seconds”

Kelli Hicks (Church Crookham, Hants) reported a fireball seen in the northern sky at approx 2115UT on July 22, describing it as having a glowing red tail. The time of this object roughly coincides with a fireball reported on Twitter as heading in a NNE direction by an observer in Felixstowe.

Peter Grego (St Dennis, Cornwall) imaged a fragmenting fireball at 2217UT on July 27, which included flares to mag -4 and mag -6 as it descended steeply towards the SSE horizon. He described it as ”appearing a golden-yellow with a bright white head. No fragmentation noted, nor was there any sign of a persistent trail. It lasted only around two seconds but it was very impressive.”

Four reports were received of a fireball, possibly around mag -7, at 0058UT on July 28. It was imaged by Alex Pratt (see below) in Leeds and by William Stewart from near Nantwich in Cheshire and was seen visually by Colin Cooper in Tynemouth, Tyne & Wear) and by Ian Matthew (Saltash, Cornwall). The end of the fireball is probably present ion an image secured by the Exmoor camera of the University of Hertfordshire. Alex described the sequence of flares near the end of its path as “Bright Flash – Very Bright Flash – Flash – Flash”. An initial analysis by Alex of the two images suggested that the fireball’s radiant was near the head of Draco.

As always, any new reports of these or other fireballs (meteors of magnitude -3 and brighter) would be welcomed by the Section.
Advice regarding what to record and where to report fireball observations to can be found at :  www.popastro.com/meteor/fireballs/makingobservations/index.php

Fireball reports from 2012 March

(This report has been compiled from the SPA Forum entry posted by Alastair McBeath)

Here is a summary of fireballs spotted from the British Isles and nearby during 2012 March.
 
March 3-4 proved to be a particularly interesting night because of the unusually long-lived fireball (perhaps lasting for 45 ± 15 seconds) which was seen very widely across the UK around 21:41-21:42 UT. Thanks to the publicity generated by that event, several other fireballs that night were reported as well, plus a fireball seen earlier in daylight on March 3rd from North Yorkshire. Many of these additional sightings can be found among those reported for the ~21:41 meteor on the American Meteor Society’s website at: 
 
or on the BBC News’ webpage for the "main" fireball: 
 
Unfortunately, the witness of the March 3 daytime event was unable to give a time for it, noting only that it was moving north to south in the sky (see BBC report 305). 
 
* The first of the overnight events on March 3-4 was around 19:10-19:15 UT, when a bright, slow, orange meteor was seen in the western sky moving southeast according to one unlocated witness, with another possible witness in Hampshire (BBC 159 & 269). 
 
* Then came the 21:41-21:42 fireball, on which 376 reports were received by the Meteor Section from all across Scotland, England and northeastern Wales. A full description of what probably happened, with links to many of the sightings and videos, can be found elsewhere on the Observing Forum, at: 
 
* At some stage within half an hour either side of 22h UT a bright yellow or white possible fireball was spotted from Exeter in Devon (AMS report 322fc). The witness there recorded it at about 45° elevation to the southeast. If correct, and this was a genuine meteor, it would have been likely high above the Channel. As the 45° elevation angle meant any object would have to have been exactly as high above the surface as it was horizontally from the observer, this cannot have been another sighting of the 21:41-21:42 UT fireball, plus it was visible for less than two seconds and had a very short path. 
 
* Within roughly five minutes of 22:25 UT, a magnitude -5/-12 event was seen from at least three places, Dublin, Lancashire and Manchester. Details from the observers suggested this fireball had plausibly occurred over the northern Irish Sea, and was likely red, orange or yellow in colour, visible for a few seconds (AMS 322fh, fi & fj). Three other reports, one from Manchester and two from Glasgow were perhaps timed between 22:30-22:35, but from the descriptions, they seemed more likely to have been mistimed observations of the 21:41-21:42 event instead (AMS 322fm, fn & fo). 
 
* Another bright meteor between 23:00 and 23:15 UT was spotted possibly from North Yorkshire and Kent. The Kent witness indicated the fireball – assuming both reports were of just the one meteor – had likely ended above the Channel to the south-southeast of Kent, or possibly over the French coast (BBC 104 & 227). 
 
* The final March 3-4 event reported to the SPA probably took place between 00:05 and 00:15 UT, according to six reports (BBC 87, 244, 259, 263, 273 & 372), although there were uncertainties in the timing of some of these. Those observers who mentioned their locations were in North Yorkshire, Norfolk, Cambridgeshire and near London, with most describing a steeply-descending meteor which may have ended over East Anglia or the nearby North Sea. 
 
* March 9-10 at 00:04 UT provided a magnitude -7/-10 meteor in their southern skies for two lucky motorists in Essex and East Sussex. The initial sighting from Essex is elsewhere on the Observing Forum, at: 
 
while that from Sussex is on the AMS’s summary page for the March 3 meteor, at: 
 
* On March 10-11, a slow-moving orange-white meteor of magnitude -2/-3 or so produced some small-scale sparkling fragmentation at circa 20:30 UT for an observer in North Yorkshire. 
 
* March 15 brought another daylight fireball report, this time from Hertfordshire at 13:02 UT, from where it was seen low to the north. 
Subsequent investigations located four other sightings beyond the original from Hertfordshire, one on the American Meteor Society’s website from Croydon: 
 
and the remaining three, from Cambridge, Suffolk and Essex, on the Lunar Meteorite Hunter’s Blogspot: 
(note that from this link address, you need to work backwards down the long list of reports to find those from March 15). 
 
Too few details were forthcoming from the witnesses to make triangulation to the object’s atmospheric path practical (though the British and Irish Meteorite Society’s Forum included a noble try, at: 
 
However, it is likely the fireball passed somewhere over northern, probably northeast, England moving towards, or maybe even above, the adjoining North Sea. Two of the witnesses reported it may have shown some fragmentation during its flight. 
 
* March 21-22, at 20:45 ± 15 minutes UT saw a magnitude -7 fireball appear for a witness in Somerset. That event was seen descending almost vertically in the western sky, not far from Venus. 
 
* March 27-28 at 01:37 UT, a magnitude -6/-7 event was recorded crossing the high SSE sky by two observers at the same site in Suffolk. The meteor was described as bright white with a hint of green. 
 
* On March 28-29 around 21:05 UT, a magnitude -3 or so orange-red meteor was seen heading northwards in the western sky from Cornwall. 
 
As always, any new reports of these or other fireballs (meteors of magnitude -3 and brighter) would be welcomed by the Section.
 
Advice on what to record and where to report to  can be found at :

2012 March 03 Fireball

(This analysis by Alastair McBeath of the widely seen UK fireball, which was visible at approx 21:41UT on 2012 March 03, originally appeared on the SPA Forum)

The final analysis of this fireball has taken rather longer than I’d anticipated, largely because of the substantial number of reports received on it, including many comments extracted from the BBC News webpage at:

www.bbc.co.uk/news/world-17248959

161 fully detailed observations from the American Meteor Society – see their website at:

www.amsmeteors.org/fireball2/public.php

and the summary page:

www.amsmeteors.org/2012/03/fireball-over-the-united-kingdom-march-3-2012/

as well as notes from Twitter. I’m especially grateful to Bob Lunsford and Mike Hankey of the AMS for alerting me to the huge number of reports they had been sent, and for making those sightings freely available to me, and to (then) Assistant SPA Meteor Director Tony Markham for rounding-up the Twitter details.

Excluding duplicates, a total of 376 reports, including 15 videos or images of part of the trail, were probably of this event, stretching from Wick and the island of Lewis in northern Scotland to Somerset, Hampshire and Essex in southern England, with several sightings from northeast Wales. Of the 353 observers whose locations could be identified, 116 were in Scotland, 168 in northern England (north of roughly 53° N latitude, somewhat variable to allow for county boundaries), 9 in Wales, and 60 in southern England.

It has been difficult to confirm some of the reports due to differences in the estimated timings, and where in the sky the object was claimed to have been seen. Outlying suggestions for the time of what was plausibly this fireball ranged from 21:00 to 22:30 UT, for instance! However, 80% fell within ten minutes of 21:41:30 UT on March 3, while the fireball most probably happened between 21:41 and 21:42 UT. The longevity of its flight, likely around 45 ± 15 seconds, meant the timing could not be more precisely-determined. A further complication has been that there were at least four, and possibly five, separate fireballs spotted from UK locations overnight on March 3-4.These are discussed elsewhere on the Observing Forum:

www.popastro.com/phpBB2/viewtopic.php

The preliminary estimate for the meteor’s trajectory given earlier has scarcely changed at all. The most plausible start area remains vaguely-defined as between the Faeroe, Shetland and Orkney Islands, perhaps within 100 km of 3.9° W, 60.5° N, assuming a start height range between 140-90 km, but it may have been some way west or north of this zone. The end area was more closely-confined to within 25 km of 0°45.3′ W, 52°13.3′ N, with a best-estimated average for its final visible height of 61.6 ± 8.5 km. As noted before, the centre of this zone on the ground was close to Bozeat, Northants, near the Northants-Beds-Bucks border.

Using this relatively fixed end-point with the data from those observers who suggested the meteor had passed overhead, or very nearly so (and excluding a few outliers), would imply the meteor’s direction of travel across the British Isles was towards azimuths 165° to 170°, so moving NNW to SSE. There was a small majority in favour of the ~170° line, which would have been above the surface track described previously – so, Orkney Mainland – Duncansby Head – Moray Firth – Banff – Inverbervie – North Sea off the Firth of Forth – near Lindisfarne, then passing overhead for Newcastle, Gateshead and Durham, as well as almost so for York, Leeds, Sheffield, Nottingham and Leicester.

Other details derived from this estimated flight-path were chiefly unchanged too, such as its intra-atmospheric trajectory being from 1060 to 900 km long, descending at between 5° to 2° from the horizontal. The larger range for its potential visible flight time, 30-60 seconds, did alter the possible atmospheric velocity range though, which would then have been circa 25 ± 10 km/sec, with no allowance for atmospheric deceleration.

An unusually large range of estimated brightnesses were suggested from magnitude -1 to brighter than the Sun (magnitude -27), although as no one reported any serious eye problems after viewing the meteor, the more extreme brightness estimates seemed more likely a result of the surprise at seeing such an amazing meteor, rather than its actual brilliance. The more reliable estimates averaged magnitude -12 or so, with the likely brightest parts of the trail probably falling in the range from magnitude -9 to -15, roughly of half to full Moon level. The object seemed to have been about at its brightest during its passage between approximately Aberdeenshire to North Yorkshire, and judging by the descriptions (albeit with an unavoidable degree of subjectivity, as not everyone agreed what happened) it may have begun breaking up or shedding small sparkling fragments from about the time it crossed the Northumberland coast onwards, or perhaps a little before then. The degree of fragmentation overall seemed relatively slight and fairly gentle however, with people often reporting a train or tail with and/or after the meteor. There was also a degree of confusion for some people about the difference between the persistent train left after the meteor had gone, and the tail seen behind the head of the meteor while still in-flight, making determining just what took place quite difficult. Some of the videos certainly would support an amount of minor fragmentation during the later flight.

Sounds potentially associated with the fireball were reported from seventeen places, twelve of those simultaneous with the meteor’s flight or almost so, five some time afterwards. The simultaneous sounds were mostly of the kind expected from previous events of this kind, described here as often quite faint, but distinct rustling, hissing, sizzling, crackling or popping. Two witnesses, one each in Derby and Wolverhampton had their attention drawn to the fireball by hearing the sound, which has also occurred before. One report from Dumfries & Galloway (the most distant place from the projected surface track to have reported a sound associated with the meteor) suggested a boom was heard a couple of seconds after the meteor vanished, much too soon for ordinary acoustic waves to have arrived at that site, but which might still have been linked to the event, although a more earthly explanation could not be ruled-out. Another witness in Manchester mentioned sounds like the whirring and banging from a helicopter were noted during the meteor’s appearance. Again, a man-made cause nearby could not be excluded. Four reports of simultaneous sounds were from Northumberland and the Borders almost directly beneath the probable line-of-flight, which provided further support for such a trajectory, with eight of the twelve within 70 km of that projected ground line.

Of the five reports of sounds after the meteor ended, two were of sonic booms from unidentified locations (one possibly in either Derbyshire or Staffordshire), and another was of a similar boom from Worksop in Notts between 60-120 seconds after the meteor vanished, another place almost directly beneath the flight-path. The remaining two reports from Glasgow, of a double shotgun-like detonation an unknown time after the meteor disappeared, and Preston in Lancs, of a rumbling noise barely audible above the local traffic about ten minutes after the meteor, seemed more likely to have had a local cause. Whether any of these delayed noises were genuinely linked to the meteor was uncertain, since assuming the fireball’s estimated trajectory was correct, it would likely have been too high to have generated such noises audibly at the surface.

As for the colours seen in the meteor, various contrasting shades were mentioned, with some people differentiating between hues noticed in the head and tail at times. Of those who reported colours in the head, most preferred red, orange or yellow (65.5%) or white (24%) with the remaining 10.5% made up of green, blue or violet.

Many thanks once more to all the contributing observers in sharing their good fortune at spotting such a marvellous, unusually persistent fireball. Man-made re-entry fireballs, which may last up to a few minutes, can be quite similar, and are relatively commoner. However, such naturally-occurring meteors skimming the meteor layer and lasting for tens of seconds are extremely rare, perhaps no more than a handful per century visible for any given place on Earth. Those who saw this one can thus count themselves particularly lucky!

Alastair McBeath

Fireball reports from 2012 February

This report has been compiled from the SPA Forum entry posted by Alastair McBeath).

 
Here is a summary of fireballs spotted from the British Isles and nearby during 2012 February:
 
* February 17-18, around 18:55 UT, produced a bright fireball perhaps over the North Sea, as seen from Perthshire & Kinross in eastern Scotland. 
 
* On February 18-19, at about 22:45 UT, a fireball of at least magnitude -4 was observed from Herefordshire. This object fragmented into three towards the end of its flight. 
 
* February 24-25 provided a bright meteor at 18:10 UT or so for another lucky witness in Perthshire & Kinross (not the same person as the previous week, however!). 
 
Any fresh reports of these or other fireballs (meteors of magnitude -3 and brighter) would be welcomed by the Section.
 
Advice on what to record and where to report to  can be found at :

http://www.popastro.com/meteor/fireballs/makingobservations/index.php

Fireball reports from 2012 January

(This report has been compiled from the SPA Forum entry posted by Alastair McBeath)

 
The notes below detail those fireballs reported to the SPA from the British Isles and nearby from 2012 January, so those interested can keep up to date with such events. Note that identified Quadrantid fireballs near their maximum on January 4 are deliberately excluded here. 
 
* January 1-2, around 21:30 UT produced a magnitude -3 or brighter event for a witness in Middlesex. The initial report is elsewhere on the Observing Forum: 
 
* On the other side of midnight on January 1-2, around 04:55 UT, a bright orange-yellow fireball was spotted from Dorset. It may have been the same as a meteor imaged by the University of Hertfordshire’ camera at Niton on the Isles of Wight, timed to within two minutes of 04:51 UT. See here: 
 
for the image, with thanks to David Entwistle for identifying this image as possibly identical. 
 
* January 7-8, ~01:11 UT produced another fireball for an observer in East Yorkshire. 
 
* January 12-13, at 18:17:09 UT ± 7 sec, provided a spectacular fireball of at least magnitude -5 that was seen very widely across southern England. Twenty five-reports have reached the Meteor Section on it so far, including two images by the Niton and Bayfordbury cameras of the Herts University’s all-sky camera system (details via Herts University analyst, David Campbell). More information can be found on the Observing Forum about this meteor, including links to the images, here: 
 
 
* Later on January 12-13, albeit rather vaguely timed somewhere between roughly 19h and 20h UT, a very bright green fireball was spotted in clouds from West Sussex, 
 
* The following evening (Jan 13-14), probably within two minutes of 20:29 UT, a further fireball was reported from west and south Wales, and probably Cumbria, with the meteor likely passing on a roughly southeast to northwest course above central-northern Wales, perhaps ending over the adjoining Irish Sea.  All three of these initial reports can be found on the UK Weather World’s Space Weather Forum, at: 
 
* A further fireball on January 13-14, at around 20:55 UT, was seen in the western sky heading northwards from Hampshire. Like the others from that night, this one’s initial report appeared on the UK Weather World’s Space Weather Forum, at: 
 
 
All additional observations of these or other fireballs (meteors of magnitude -3 and brighter) would be welcomed by the Section. Advice on what to report and where to report to  can be found at: 

2012 Quadrantids

Completing the round-up of shower reports prior to my standing-down as SPA Meteor Director in 2012 April, we reach the 2012 Quadrantids.

Weather conditions were certainly kinder globally for this shower than others during the latter months of 2011, although the late-setting gibbous Moon restricted useful visual watching times quite considerably. UK observations were sadly few once again, and although support from the Section’s overseas contributors was excellent, the IMO’s visual dataset was of course much more complete even than these, and it is this which is used as the primary source of comparison information here. Two peaks were apparent in those results on January 4th, one around 05h-09h UT (average ZHRs ~ 80 ± 5), the other between roughly 17h-20:30 UT (average ZHRs ~ 75 ± 10), albeit the second maximum was based on a much smaller meteor sample. In between, and with a gap from about 14h-17h when no data were collected, activity seemed to have dropped to ~50 or so. There was also a drop to ZHRs of ~ 55 ± 10 in the hour centred at 07:40 UT during the first peak, although its significance was unclear as based on few meteors.

The IMO’s Quadrantid video observations featured in that Organization’s journal “WGN” 40:2 for 2012 April, pp. 76-79, notably pp. 76-77. These did not show a clear maximum at all, simply steeply rising rates overnight from Europe towards dawn on January 3-4. The estimated visual-ZHR-equivalent by circa 06h UT then was ~70. Unfortunately, no data were collected soon after the start of the following European night, thus no results were available to confirm the second IMO visual peak. Consequently, that feature has remained somewhat tentative.

Drawing on the radio results provided to the SPA, two main maxima were apparent on January 4th, from approximately 04h-06h and 11h-15h UT (recalling that the radio data are usually provided only in one-hour sampling intervals, so no greater temporal accuracy than to the nearest hour is possible). A much weaker possible third peak was found from 18h-20h UT or so, perhaps extending until 22h. The early part of the first radio maximum, through to the drop around 08h, mirrored the IMO visual findings fairly closely, but after that, the results diverged significantly, either in terms of peak timing for the second visual and radio maxima, or strength for the potential third event in both.

Careful checking of the data more closely suggested the second radio peak, though plausibly real, was perhaps of lesser significance than the first, as it happened at a time when the Quadrantid radiant was around its best-detectable from both the two main geographic observing regions, Europe and North America. The tertiary radio peak may similarly have been of somewhat more importance than its minor signature indicated, as it happened during the worst possible time for European observers, though all three maxima featured in data from both observing zones.

Quite why the visual and radio patterns were not closely identical after the first peak is uncertain. It is particularly curious the visual rates were not more impressive during the second radio maximum, as this was apparent in all the available, if limited, longer-duration radio echo data, which showed a distinct peak in the hour beginning at 12:00 UT, data which is generally supposed to be more representative of meteors that should be readily observed visually. The better-confirmed radio-visual “primary” peak was reasonably close to the predicted maximum time, at least!

The list of observers who contributed to this Quadrantid report can be found on the SPA Forum at :  forum.popastro.com/viewtopic.php

Alastair McBeath
Assistant Meteor Director, Society for Popular Astronomy

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: 
 
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:
and the University of Hertfordshire at Bayfordbury, Herts:
 
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: 
 
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.

2011 Ursids

Here is Alastair McBeath’s analysis of the 2011 Ursids :

Following the disappointing run of badly moonlit, and commonly badly weather-affected, meteor showers in late 2011, sadly the moonless Ursids seemed to have done no better for clearer skies, with scarcely no visual reports received by either the International Meteor Organization (IMO) or SPA. However, as the two advance possible maximum predictions noted earlier here were joined barely a day before the event by a third, suggesting peak ZHRs of ~10-15 on top of the usual activity might happen just before 18h UT on December 22, it has been important since to try to establish what may have taken place.

Data from the IMO’s video observations of the shower were discussed briefly in the Organization’s journal “WGN” 40:2 for 2012 April, pp. 69-75, especially pp. 70-71. They indicated just a single sharp peak had been found at 19h UT on December 22, with an estimated visual-ZHR-equivalent of ~15, although being based largely on European results, any events during European daytime could have been missed.

As the Ursid radiant is circumpolar for all our usual northern hemisphere radio meteor observers, located in Europe and North America primarily, it is one of those rare showers whose activity can be followed from all locations throughout the day and night, interference and other technical problems permitting! Carrying out the usual analysis of this data suggested that Ursid activity had probably been present at a radio-detectable level from roughly 02h UT on December 22 through to at least 11h UT on the 23rd. Within that time, the main shower maximum was undoubtedly in the 19:00-20:00 UT interval on the 22nd (remembering that most radio observers provide data in one-hour long recording periods only). It was surrounded by a spell of better than normal, but below-peak, rates from circa 16h-22h. Judging the strength of meteor activity purely from radio data is extremely difficult, although in this case, it was plausible the Ursid activity was fairly normal, so likely close to ZHRs of ~10-15. This was all reassuringly similar to what the IMO video data had proposed.

There appeared to have been several lesser radio maxima as well, although these were generally less convincingly recorded than the main one. Ignoring those which likely resulted solely from better radiant geometry from the two chief geographic regions, those on December 22 around 10h-12h and on December 23 around 07h UT remained as potentially interesting. Unhappily, the lack of other data meant no further investigation of these could be performed.

It remains intriguing that none of the predicted maximum timings coincided at all well with what was actually found, stressing the importance of making observations for as long as possible whenever a meteor shower peak is due, rather than relying heavily on what is “supposed” to happen!

A list of observers whose reports were used in this analysis can be found on the SPA Forum at forum.popastro.com/viewtopic.php