Meteor Over the United Kingdom

Originally posted by FireballStorm

Originally posted by abeverage
I think often a meteorite is mistaken for a comet.

I think you mean "a meteor is mistaken for a comet"! A meteorite is a meteoroid that has made it through the atmosphere and is found on the ground.

You are right that meteors are misidentified as comets sometimes, although it's more common in my experience that they are mistaken for planes (on fire/in the process of crashing), or fireworks.

Originally posted by abeverage
Although meteorites typically move quickly across the sky, if they are at the right angle they can skip across our atmosphere for several minutes!

"Several minutes" is a bit of an exaggeration. The slowest moving earthgrazing meteors won't be visible for more that around a minute in the most extreme cases. There has certainly never been a confirmed case where a meteor has been visible for multiple minutes. If I recall, the record is 72 seconds, and is held by the Peekskill meteorite/fireball.

A man-made reentry however can be visible for multiple minutes, since objects in orbit are slower moving than natural meteoroids.

Actually I meant meteoroid, but it was before my morning coffee. I guess if I am to correct I should expect to be corrected. And yeah I said minutes as it could have been a cluster...
en.wikipedia.org...

Originally posted by abeverage
And yeah I said minutes as it could have been a cluster...
en.wikipedia.org...

Granted, a cluster is a possibility, but events of this type are exceptionally rare.

Most meteoroids don't linger in orbit for a while before breaking up and entering the atmosphere. So I stand by what I said, despite this rare exception.

Still, nice to see the meteor procession of 1913 brought up on ATS

Originally posted by FireballStorm

Originally posted by abeverage
And yeah I said minutes as it could have been a cluster...
en.wikipedia.org...

Granted, a cluster is a possibility, but events of this type are exceptionally rare.

Most meteoroids don't linger in orbit for a while before breaking up and entering the atmosphere. So I stand by what I said, despite this rare exception.

Still, nice to see the meteor procession of 1913 brought up on ATS

I remember seeing the film of the 1972 Daylight Fireball as kid and it is still a lasting memory of how lucky we are! But also it peaked my curiosity and help lead me into being an amateur astronomer who still makes amateur mistakes…

apod.nasa.gov...

Rare as it might be unless we get something official saying it was space junk what else would be seen for that long?

Originally posted by abeverage
I remember seeing the film of the 1972 Daylight Fireball as kid and it is still a lasting memory of how lucky we are! But also it peaked my curiosity and help lead me into being an amateur astronomer who still makes amateur mistakes…

As we all do. I'm sure even pros make amateur mistakes from time to time.

I agree, we are lucky to live in an amazing universe. A night spent observing the Leonid "fireball storm" of 1998 (by a stroke of pure luck - the Leonid peak that year was forecast for the following night) is what first got me interested in astronomy, especially meteors/fireballs.

Originally posted by abeverage
Rare as it might be unless we get something official saying it was space junk what else would be seen for that long?

I'm not sure that there were any confirmed reports of the UK fireball lasting over a minute, although I did suggest that this may have been the case earlier in the thread - but it's not uncommon for reported descriptions of events like this to be inaccurate. It's rare for people to be watching a clock whilst observing a big meteor, and when adrenalin kicks in perceived timings can be way off.

The only way to be sure is to analyze the footage that is available, and thankfully there is a fair bit, so there is a good chance we will find out.

I am still not so sure that it wasn't a satellite/junk reentry, despite the reasons mentioned earlier in this thread that make it less probable. To that end, most of last night was spent stacking frames from fireball footage to try and get some star detail and work out a precise track of the object in the sky, but to no avail alas. It's a bit of a long shot anyway.

I am slowly starting to think that the odds are tipping in favor of it being a normal very-slow natural fireball, perhaps even a rare cluster, but it's less likely than the other two possibilities I think.

Originally posted by FireballStorm
The only way to be sure is to analyze the footage that is available, and thankfully there is a fair bit, so there is a good chance we will find out.

I am still not so sure that it wasn't a satellite/junk reentry, despite the reasons mentioned earlier in this thread that make it less probable. To that end, most of last night was spent stacking frames from fireball footage to try and get some star detail and work out a precise track of the object in the sky, but to no avail alas. It's a bit of a long shot anyway.

I am slowly starting to think that the odds are tipping in favor of it being a normal very-slow natural fireball, perhaps even a rare cluster, but it's less likely than the other two possibilities I think.

I would be curious to your findings. You are stacking to get more detail in the background? You use deepsky for this or something else?

Originally posted by abeverage
I would be curious to your findings. You are stacking to get more detail in the background?

Yes. With the original footage only two stars are clearly visible, so I'm trying to bring out a few more stars so that I can work out what stars/constellations are in the camera's field of view.

Originally posted by abeverage
You use deepsky for this or something else?

I'm using Photoshop.

Here is the footage:



This is the best result I could get after increasing the exposure, using curves, and heavy sharpening. I've marked what I think are stars with green dots.


Here's a full size version, without any green dots/heavy sharpening.


Here's the stack in PSD format
www.sendspace.com...

Here's the stack in TIF format
www.sendspace.com...

Note that at the bottom of the frame, the location of the camera and "WSW" (which I assume is the direction the camera is pointing) is stamped on the footage.

Note also that there appears to be the top of a tree (or it could just be light pollution) at the bottom of the frame, which suggests the camera was pointing fairly low down in the sky.

Approximate coordinates of the camera:
54.150271,-9.733129
(Bangor, Co. Mayo, Ireland)

If yourself (or anyone else) wants to help to identify which stars we are looking at, please feel free to have a go. If necessary I can upload different formats.

reply to post by FireballStorm


I seen it burn out as it traveled over the Irish sea/ Ireland, I am right on the North West coast.

From it came into view (or should I say when I noticed it) from the east, till it disappeared, I would say definitely no more than a minute.

I have just been down to where I seen it and recreated my actions, including fumbling with my phone trying to get the damn camera app open.

reply to post by FireballStorm


Well we have the time, date and (do we have supposed direction?). Should be easy enough to throw into Stellarium if that is what you are planning to do. I could verify for you if get some time. Other then that I am lousy at tracking or calculating orbits.

reply to post by woogleuk


As I suspected... but, when you first caught sight of it, had it already started to break up?

Did you see the object/objects "burn out" before you lost them behind buildings/trees?

Originally posted by abeverage
Well we have the time, date and (do we have supposed direction?).

Apparently the camera was pointing WSW.

Originally posted by abeverage
Should be easy enough to throw into Stellarium if that is what you are planning to do..

I've just been using SkyMap Pro and comparing that side-by-side with the enhanced stacks.

Does Stellarium allow you to load up an image and then checks for matches itself? If so that would be very useful.

Originally posted by abeverage
I could verify for you if get some time.

If you could, that would be great!

Originally posted by abeverage
Other then that I am lousy at tracking or calculating orbits.

Me too, but we don't need to calculate orbits - just need to get a rough idea of the objects path in the sky in relation to the stars. I've outlined how I intend to identify any possible satellites/junk in this thread here, and there are some more examples here if you are interested.

I'm sure others are working on calculating orbits right now, if it has not been done already.

sorry in advance but im a newbie and cant figure out how to post my own uestion on here and really wanted to ask 1 about the sand filled foam in aberdeen todayy ? sorry for butting in on this post

It looks like we have a winner...a natural earth-grazing meteor, and it may well have had elements of a "cluster event" as abeverage suggested

[meteorite-list] Trajectory for Earth-grazing UK bolide of 9/21/2012

Matson, Robert D. ROBERT.D.MATSON at saic.com
Tue Sep 25 18:54:00 EDT 2012

-snip-

Let me start with the analysis result, since it's pretty exciting:
the UK bolide of 21 September 2012 was an earth-grazer: it's pre-
earth-encounter trajectory did NOT intersect the earth! It came
very close -- a minimum altitude of about 57 km over western Ireland.
Coincidentally, this is the same minimum altitude that was
achieved by the Grand Teton Daytime Fireball of 1972, although
that encounter lacked the significant fragmentation seen last
Friday.) Thanks to that fragmentation coupled with the low altitude,
some meteorites may have actually made it to the ground (or more
likely the ocean). But a significant fraction of the original
meteoroid went right back into space. Depending on the velocity
(which I would need a good video to estimate), the original
asteroid's orbit may have been sufficiently aerobraked to have
been captured by earth's gravity. If so, then the remaining fragments
would have reentered for good one orbit later in the middle of
the North Atlantic.

I know this is a bit of bad news as far as meteorite recovery, but
it's nevertheless an important result since it is one of the
extremely rare instances of an earth-grazing asteroid being not
only witnessed by hundreds if not thousands of people, but also
imaged by multiple cameras, both still and video.

More at the source: meteorite-list



Three images of the fireball were used to calculate the trajectory/orbit:

www.worldirish.com...

1. Damien Stenson's beautiful image taken just south of O'Brien's
Tower on the Cliffs of Moher in County Clare, Ireland. At least
four bright fragments pass through the bowl of the Big Dipper,
behind the central tower and then disappear behind clouds low
in the west-northwest.

www.bbc.co.uk...

2. Craig Usher's shot from Greenock, Scotland, facing southwest
shows the tracks of at least five individual fragments. Four of
these appear to be the same ones captured by Damien Stenson.

www.aftenposten.no...

3. Truls Gabrielsen's time-lapse photography from Skjernøya,
Mandal, Norge (southern Norway) includes two frames showing the
bolide track very low in the southwest sky:

reply to post by FireballStorm


It literaly started to break up as I first seen it, that's why I thought for a brief moment it was fireworks.

I had a clear view of the Horizon straight off the north west coast, I never lost sight of it until it faded out.

On a clear day, I can see the Isle of Man, the mountains of Ireland, and Scotland over the Irish sea / Solway Firth.

an earth grazer?!

I thought this was the VIP alien transport arriving early for the 2012 show

I'm surprised that there was so much interest in this fireball, and what it may have been, but so little interest now that the mystery has been solved.

Just one reply? What gives?

It seems that people are disappointed because this wasn't something more unusual than a natural fireball.

This was an unusual natural fireball though, and probably the most "historic" natural fireball event since the Great Lakes fireball of 1972!

Here is further confirmation that the object was indeed a natural fireball, from two independent sources, both of whom are well known and respected within the scientific community.


Firstly Alastair McBeath (Assistant Meteor Director, Society for Popular Astronomy):

Early press coverage also suggested the event may have been a man-made re-entry. However, if we assume the average visible duration noted above was roughly correct, and that the full visible path was between circa 500 to 1000 km long as a crude estimate, the object's velocity, not allowing for deceleration, would have been well above any near-Earth man-made object's, but comfortably within the expected meteor atmospheric-entry range, between ~20 to 40 km/sec.

More here


Secondly Dr. Marco Langbroek of the Dutch Meteor Society, who is also an amateur satellite tracker.

More on the 21 September 2012 fireball: why it definitely was a meteor

Observers report durations between 20-60 seconds: most video's on the web suggest a 40+ seconds duration.

It would take a reentering satellite travelling at 8 km/s (the orbital speed at decay altitudes) about 138 seconds or roughly 2.25 minutes to travel this distance. While the reported fireball durations are long, none of the reports nor videos comes even remotely close to that value.

A meteoric fireball travelling at the lowest speed possible for such an object, 11.8 km/s, would take 93 seconds to travel that distance. This is still longer than almost all of the reports suggest, but clearly getting closer.

If we take an estimated duration of 60 seconds, the 1100 km trajectory length results in a speed of approximately 18 km/s.

18 km/s is a very reasonable speed for a slow, asteroidal origin fireball.

(it is, let me repeat, also way too fast for a satellite reentry).

Meteorite dropping fireballs typically have speeds between 11.8 and 27 km/s. A speed near 18 km/s sits squarely in the middle of that speed interval.

Edit to add graph:



He goes on to say:

Note 2: on how I made this quick and (emphasis) rough trajectory reconstruction. I took observations that contain clear sky locations: e.g. a sighting from Dublin stating it went "through the pan of the Big Dipper"; the description from Bussloo observatory in the Netherlands; and later adding a.o. a photo from Halifax, UK, showing it just above the tail of Ursa Major. These descriptions can be turned into directions and elevations. Next, I drew lines from these sighting points towards the indicated directions, marking distances roughly corresponding to 30, 50 and 80 km altitude as indicated by the observed elevation [ distance = altitude / tan(elevation) ]. Near the start of the trajectory I marked 50 and 80 km, for Britain and Ireland I marked 30 and 50 km. These points then provide you with a rough trajectory.
From Dublin the object passed through North towards west. From Bussloo the object started NE (azimuth 60 degrees): these are important points of information too as it shows that the object started at least as far east as the Dutch-German border (and more likely over Sleswig-Holstein in N-Germany) and had its endpoint at least as far west as the northern part of Ireland.

More here



Here's the latest update from him..

[UPDATED] The 21 September fireball: a small Aten asteroid?

In my previous post I presented clear evidence that the splendid fireball seen over NW Europe on September 21st, 2012, was a meteoric fireball. I also presented a first, very preliminary idea of its trajectory.

Based on that trajectory, I can now present some very first, very cautious conclusions about the heliocentric orbit of this meteoroid.The solutions strongly favour an identification as an Aten asteroid.

More here

The Aten asteroids are a group of near-Earth asteroids, named after the first of the group to be discovered (2062 Aten, discovered January 7, 1976, by Eleanor F. Helin). They are defined by having semi-major axes of less than one astronomical unit (the distance from the Earth to the Sun). Because asteroids' orbits can be highly eccentric, an Aten orbit need not be entirely contained within Earth's orbit; in fact, nearly all known Aten asteroids have their aphelion greater than one AU even though their semi-major axis is less than one AU. Observation of objects inferior to the Earth's orbit is difficult and may be the cause of some bias in the apparent preponderance of eccentric Atens.

Source: Wikipedia

If that in the video regarding what was on the UK skies was a "meteor" or as someone also mentioned "space-junk" then I'm the queen of England.

I don't recall "meteors" or "space-junks" having light dots around it and moving at such a slow speed not to mention the alternate trajectory it appears to have.

Why do people speculate on things they don't understand is beyond my mind...

reply to post by shenk


Lovely to see you on here maam

It is true, lots of people on ATS speculate from an inexperienced position... but not everyone here is inexperienced when it comes to this subject.

Originally posted by shenk
I don't recall "meteors" or "space-junks" having light dots around it and moving at such a slow speed

Weather you have come across such an event in the past or not, the fact remains that meteoroids do fragment, and there is plenty of evidence for it being real.

For example the Peekskill meteor, which can clearly be seen to fragment.


Admittedly, the fragments in this case do not behave quite like those from the Peekskill fireball, but that is because the UK fireball was a very unusual type of fireball!

Have you ever seen footage of a meteoroid that was temporarily captured by Earth's gravity causing a fireball before? If not, then why would you expect to see what looks like footage from a more ordinary fireball???

Big Meteoroid Boomerangs Around Earth
For the first time ever, a meteor has grazed in and out of Earth's atmosphere, slowing enough to become a temporary satellite that perhaps lasted a full orbit.

Source: Sky and Telescope

And because it was "slow", in your experience (which is obviously very limited in this particular field, or you would know that meteors can be slow, especially in unusual cases like this one), it "can't have been one"?

Perhaps you should take your own advice:

Originally posted by shenk
Why do people speculate on things they don't understand is beyond my mind...

...and not speculate about things that you don't understand.

Ok here something new to the UK Meteor

UK Earth-hugging Asteroid Circled the Earth and Hit Again
The following news is published jointly by Tähdet ja avaruus -magazine of
Finland.
lunarmeteoritehunters.blogspot.ca...

This is really getting interesting if I may say so.

Originally posted by Trillium
Ok here something new to the UK Meteor

UK Earth-hugging Asteroid Circled the Earth and Hit Again
The following news is published jointly by Tähdet ja avaruus -magazine of
Finland.
lunarmeteoritehunters.blogspot.ca...

Yeah - I've been following this angle here

This thread is dead

Originally posted by Trillium
This is really getting interesting if I may say so.

Been saying that for a while... but no one seems interested.