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Posted by: paxdan Dec 6 2005, 05:52 PM

Google maps showing http://geology.com/meteor-impact-craters.shtml. Pretty neat stuff.

Posted by: blobrana Dec 6 2005, 08:07 PM

Yeah,
Pretty neat stuff.

Though, for those that prefer to use Google Earth (the .exe)

http://www.googleearthhacks.com/dlcat34/Craters.htm

There is better coverage...

Posted by: Jyril Dec 6 2005, 08:28 PM

It's badly incomplete. Google Earth in turn has most craters marked several times.

Posted by: ElkGroveDan Dec 6 2005, 08:59 PM

Agreed, I see Odessa, Texas (visible in Google Earth at 31 45.40 N, 102 28.74 W) is missing and probably 30 or 40 others

Posted by: Jyril Dec 6 2005, 09:16 PM

Many more. For example, all European, Russian, and South American craters are missing.

Posted by: Pando Dec 7 2005, 06:48 AM

Perhaps the one best resources is this Google Earth placemark located here which contains about 175 locations for known impact craters. If you have Google Earth installed and click on the "Open the Placemark" file, it will list and show all those locations on the GE globe, along with the diameter and approximate age.

http://bbs.keyhole.com/ubb/showthreaded.php?Cat=&Board=EarthNature&Number=30566

Also, here is a full impact tour with overlays:

http://bbs.keyhole.com/ubb/showthreaded.php/Cat/0/Number/71111/page/0

Posted by: Steffen Jan 9 2006, 07:02 AM

That Google Earth application is really ashtonishing !!!
http://earth.google.com/downloads.html

Posted by: lyford Jan 13 2006, 07:30 PM

Mac users (if you are running Tiger 10.4) might want to try that link again now...

Posted by: CosmicRocker Feb 23 2006, 05:47 AM

I don't always keep up with this thread because Google Earth is _so_ slow on my dialup connection, but it is pretty amazing. I thought some of you might be interested in this news I just received in a Google Friends newsletter.

"Google Friends Newsletter
February 2006

February salutations to Google Friends everywhere. We hope you enjoy this update on Google services and new products. At the bottom of this message, you'll find details on subscribing to or canceling this newsletter.

POWER TIP
Winter Games Enhanced
We've updated Google Earth and Google Local with high resolution imagery of the area surrounding Torino, Italy, home of the 2006 Winter Games. With Google Earth installed, click on the KMZ file for Olympic Venues, which will load placemarks for all the major sites at the Games. To really appreciate the scenery, be sure to enable the Terrain layer and take advantage of the tilt view control in Google Earth:
We've also generated street maps for Torino, which are available in the Google Maps API for those of you interested in creating Winter Games mashups.
http://earth.google.com
http://local.google.com (search on 'Turin' or 'Torino')

This Google Blog post features even more Games-related news:
http://googleblog.blogspot.com/2006/02/gamesmanship.html ..."
I haven't tried it, since my pipeline is more like a capillary tube, but if I know Google, they should be pretty nice views, and some of you in the lucky countries can ply your skills to win the Fiat Sedici mentioned in the last link.

Posted by: paxdan Mar 6 2006, 12:04 PM

Space.com are reporting a http://www.space.com/scienceastronomy/060303_big_crater.html. I imagine that name will be familar to those who have read Chaikin's 'A Man on the Moon'. A quick google shows yep it's the same guy

edit: http://maps.google.co.uk/?ll=24.681961,24.99939&spn=0.353758,0.455246&t=h I found it in about thirty seconds based on the description in the article "Western Desert of Egypt at the border with Libya"

makes you wonder how much other stuff is to be discoverd

Posted by: volcanopele Mar 6 2006, 06:47 PM

http://www.googleearthhacks.com/dlfile14350/Mahuika-crater.htm

I have never heard of this?!? Wow, a 20 km crater formed in 1443. Anyone know of any good links for info on this?!?

EDIT: Did some google searches. Looks like this is complete garbage (I figured as such, an impact of that size would be kinda noticeable.

Posted by: blobrana Mar 6 2006, 07:18 PM

LOL,
i posted that garbage...

Take it from me that the evidence is there....(yes really)


Hum,
i found this in a few clicks

http://gsa.confex.com/gsa/2003AM/finalprogram/abstract_66116.htm

Posted by: volcanopele Mar 6 2006, 08:28 PM

Okay, not garbage, but it certainly is controversial, particularly on the age of the impact, and the connection to south pacific tsunamis in the 15th Century.

Posted by: blobrana Mar 6 2006, 10:53 PM

Hum,
Well i suppose that the relatively recent date may shock a few people, and that it have been controversial a few years ago...
But, Dallas Abbott of the Lamont-Doherty Earth Observatory (LDEO) and her colleagues analysed melt water from nine samples taken from the West Antarctic Siple Dome ice core that date between 1440 and 1448 A.D. and found high values of potassium and calcium as well as impact glass, microcrystalline magnetite, minerals and five microfossils corresponding to the 1443 A.D. level.
Several pieces of evidence point to Mahuika as the source ...


http://www.earth2class.org/k12/w8_s2004/content.htm
http://www.usnews.com/usnews/culture/articles/031208/8meteor_2.htm
http://abob.libs.uga.edu/bobk/ccc/cc120403.html

Posted by: edstrick Mar 7 2006, 08:31 AM

Farouk El-Baz gave a talk at a planetary science meeting I was at in the early 80's, probably, more a travelogue than a science talk. May have been a dinner or other non-session presentation.

He had led (I believe) a major comparative planetology expedition to "Chinese Mongolia" or some nearby deserts in the far interior northwest of China. This was an international expedition, not long after "red" China had re-opened to outsiders. The locals, probably Uighur or another Turkic ethnicity, knew each other and their ethnic chinese overlords, but had had no contact with true outsiders. They were apparently totally blown away by how DIFFERENT the various visitors were from each other. Americans of various ethnicities, including a black planetary geologicst, an Egyptian arab.... I don't know who all.

Farouk's a really nice guy, a solidly good scientist, one hell of an international organizer... I hope to <bleep> he writes an autobiography someday.

Posted by: Bob Shaw Mar 7 2006, 10:50 AM

You obviously have a handle on these matters, so I wonder if I can send another hare out for the dogs to chase?

Are there any impact sites identified with the Australian tektites?

Bob Shaw

Posted by: edstrick Mar 7 2006, 11:07 AM

Last I heard that a likely location for the source for the austral-asian strewn field of tektites was entirely buried under the sediments of the Meking river plains in Cambodia. Some source in that very very general area on continental crust seems required, but there's no sign of a source crater anywhere, and that's the largest area of thoroughally sediment-buried crust anywhere around.

High-resolution geophysical prospecting/maping (gravity and magnetics) would find it, but getting permission is.........

Posted by: blobrana Mar 7 2006, 01:49 PM

Hum,
Yeah a bit of a mystery there...

Australites (and Indochinites which are indistinguishable from each other) have been dated to about 710,000 years using fission track and potassium-argon (K-Ar) dating methods; However the stratigraphic positions indicates an age of 7000 to 20,000 years BP.
From their chemical composition, both belong to the same impact event...!

The evidence seems to show a least two episodes of australite falls - one relatively recent (24,000 and 16,000 years ago) and at 710,000years. (It could be influenced by sorting by ie Early man)
Australites are also unusual in that some show that they were remelted; this may show different trajectories - sending some material into orbit...

Darwin glass from South West Tasmania has a combined K-Ar and fission track age of 730,000 +/- 40,000 years. It seems that Darwin crater was the source of both.
I would also add that it is possible that the impact crater may be part of two or more events that occurred together. Another associated impact crater could have been formed in the Indonesian region.
A larger impact crater that still has to be found...
Darwin Crater has a diameter of 1 km


http://static.flickr.com/38/109194595_6f6d697998_o.jpg
(This is a possible location - can someone confirm?)
-42.249599° 145.555629°

(i`ve posted another location (42°18.39'S, 145°39.41'E) at googlehacks though)

http://www.grisda.org/origins/04076.htm

Posted by: blobrana Mar 17 2006, 01:23 PM

Hum,
i ve just remembered another possibility for the Australites.

“An asteroid between 5 - 11 km across had broken up in the atmosphere and five large pieces had hit the Earth, creating multiple craters over an scatter ellipse area in Antarctica.
Scatter ellipses such as this accompany all such multiple impact sites, except that the Antarctic ellipse is the largest known on Earth. Of the five new impact craters, three of them are on the continental land mass and two more are in the Weddell Sea. The largest of these craters is about 322km by 322km.
The Antarctic scatter ellipse is of enormous size by Earth standards, measuring some 2,092 kilometres by 3,862 kilometres. Melted rocky debris, blasted from such meteoroid craters upon impact and explosion, and known as tektites, may have been carried thousands of kilometres from the impact site. Such tektites, called australites, are found in large strewn fields in Australia some 5600 kilometres from the largest proposed impact sites in the Ross Sea region.

The impacts occurred roughly 780,000 years ago during an ice age. When the impacts hit, they would have melted through the ice and through the crust below.”

http://www.gmat.unsw.edu.au/wang/jgps/v1n1/v1n1pH.pdf (PDF)

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V61-4GBD6VK-1&_coverDate=07%2F15%2F2005&_alid=354238467&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=5801&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=ac5e849e788ca4453daac17c134d20ea

http://www.rense.com/general56/strike.htm

http://news.bbc.co.uk/2/hi/science/nature/4816794.stm

Posted by: blobrana May 27 2006, 10:51 PM

Hum,
just for the record - (i can`t find this information anywhere on the net!)...The location of Darwin Crater is at

Latitude = -42.30483 Longitude = 145.65883

http://static.flickr.com/64/154400280_5b2757ad1e_m.jpg

Posted by: Bob Shaw May 27 2006, 11:01 PM

Blobrana:

I have several tektites from both fields (Australites and Indochinites), which are always a joy to tell people about! When asked to identify the object, the most common reaction is 'fossilised turd'. I have an ace up my sleeve in such cases to deal with smartarses - a genuine coprolite, a fossilised turtle poo!

Bob Shaw

Posted by: DonPMitchell May 28 2006, 04:24 PM

You might remember this photo of a meteor, taken a few years ago. I saved the picture, but I didn't save any information about who took it or where.

[attachment=5911:attachment]

I just now tried to locate the Tunguska impact in Siberia. This was an airburst impact, perhaps of an icy object, that leveled trees with its shockwave. You can't really see anything there now, at the resolution of Google Earth:

[attachment=5914:attachment] [attachment=5913:attachment]

Posted by: Bob Shaw May 28 2006, 05:27 PM

Don:

I seem to remember that picture of the 'airburst' turned up on APOD, but then got debunked!

Bob Shaw

Posted by: blobrana May 28 2006, 06:51 PM

Hum,
looked real to me...

http://news.bbc.co.uk/1/hi/wales/south_east/3155928.stm

Posted by: DonPMitchell May 28 2006, 07:51 PM

Intersting, I saw the first story on BBC. Just googling around, it appears that this is an unresolved topic. First NASA said it was an meteor, a "sofa sized rock". Then a few days later they announced it was just the sun shining on a jet contrail (doesn't look like that to me). Then a second photo of the object turned up, taken by a man in Scotland:

[attachment=5921:attachment]

And here is Burnett's second photo:

[attachment=5922:attachment]

In the photo from Scotland, the curve of the trail makes me think it is not a meteor. Here's more what they should look like:

[attachment=5923:attachment]

Posted by: helvick May 28 2006, 08:30 PM

I've seen one nighttime fairly large bolide - can't remember precisely when cos I was a lot younger (early 1980's can't remember which one exactly) but it was summertime (August I think in the Northern hemisphere) around 11:00 - 11:30 BST so it was reasonably dark. I initially thought it was an emergency flare of some sort but almost immediately realised that it was incredibly bright - at least full moon bright and more than bright enough to cast very distinct shadows over as far as I could see. It looked exactly like your last picture and nothing like the first - intense blue\white with a clearly defined teardrop shape. I can't recall how long it remained visible - probably no more than a couple of seconds but it was much longer than a typical meteor streak, sufficiently long for me to react to it and stare for a while and realise that this was lighting up the entire coastline - I recall that I could see places more than 10 miles away clearly however in hindsight that seems a bit fancyful. It was an awe inspiring sight though, not quite as awesome as a full eclipse must be, but it really does make you feel quite small and insignificant.

It was mentioned in the Irish news media the following day that Astronomy ireland were looking for anyone who had seen it who could give them any specifics on it's position but at the time I didn't know enough about such things to be of any help.

Anyway to return from that aside - my gut feel (uh-oh Shaka will be after me) is that the "dumped fuel igniting in a jet exhaust" explanation that is buried in the comments on the BBC article seems most probable to me. But this is just a gut feel - I've no personal experience of igniting jet fuel at high altitude and velocity (unfortunately).

Posted by: Bob Shaw May 29 2006, 03:37 AM

I saw a *major* fireball whilst out one night in the countryside near Dumfries, in SW Scotland in 1972. The damn thing gave me such a fright that I fell off my bicycle! I understand that it also fell in Northern Ireland, prompting a security scare. It was certainly very bright, and lit up the whole sky - though my fading memory insists that the ground was still dark.

Funny that Ireland should be so lucky!

Bob Shaw

Posted by: dvandorn May 29 2006, 06:29 AM

Several years ago, I was driving through Wisconsin at about 2 a.m. In the wilds of Wisconsin, it gets pretty dark out, and there was no Moon that night.

I saw a fireball that came over the horizon just at the left extremity of my windshield view and then arced across the sky, directly in my field of view. It was bright blue-white, leaving a greenish trail behind it. As it approached the far horizon, almost exactly aimed at the right visual limit of the windshield, it appeared to fragment and explode into sparkles.

There was, as I say, no Moon, so this thing looked very bright to me, but it might not have been super-bright. (I did see it very clearly over the glare of my headlights on the road ahead of me, though.) One thing I do recall, the *entire* trail glowed with a greenish glow for several seconds after the event. It was too dark to see a contrail after that glow dissipated, I'm sorry to say. The area where the fireball seemed to explode seemed to glow for several more seconds than the rest of the trail, maybe for as long as 10 or 15 seconds.

I'd guess that the whole traverse of my visual field took maybe one and a half seconds -- too fast for a re-entering satellite.

That was the brightest fireball I've ever seen, although the "meteor storm" a few years back was one of the most fascinating meteor events I've ever seen. You'd get clusters of trails, not just the occasional streak. I was looking directly at the source point in the sky when a starburst of five meteors flashed towards me, making a near-perfect five-pointed star in the sky... That was simply spectacular!

-the other Doug

Posted by: blobrana Jun 9 2006, 03:35 PM

Hum,
Northern Norway was hit with an meteorite impact comparable to the atomic bomb on Wednesday, 7th June, 2006.
For several seconds, residents of the northern part of Troms and the western areas of Finnmark saw a ball of fire crossing the sky.
A few minutes later an impact was heard and geophysics and seismology stations in Karasjok registered a powerful sound and seismic disturbances at 02:13.25 a.m.
The meteorite hit a mountainside in Reisadalen in North Troms, and was probably the largest known to have struck Norway.

Latitude 69.498379° Longitude 21.428999°
(As the actual impact site hasn't been found the attached image is centred on Reisadalen.)

Posted by: Rob Pinnegar Jun 9 2006, 04:44 PM

Guess all the local universities will be sending people up there to look for the crater! That would be an interesting trip. At least it's at the right time of year, eh? They'll be able to look for it 24 hours a day.

Posted by: DDAVIS Jun 9 2006, 05:44 PM

[quote name='blobrana' date='May 28 2006, 06:51 PM' post='56073']
Hum,
looked real to me...

The image resembles clouds under similar lighting that I have seen before. The second image with the redder lighting betrays the nature of the changing light on the uneven contrail as sunset proceeds. There is a New Zealand video which began shorly after a massive airburst, showing as I recall a dense trail, a weak mushroom like cloud vortex rising from its lower end, below which falls vertically considerable debris. Theis tap contains the first known audio recording od a double boon from a fireball.



I took a picture that looks like a meteor blazing above the clouds, but it was an uneven contrail, and I removed in Photoshop a few shreds on one side just for laughs. it is at the top of this page:


http://www.donaldedavis.com/PARTS/ODDITIES.html

Don

Posted by: Myran Jun 10 2006, 06:42 AM

Yes and its so typical anything coming from USA i can only sigh in despair.

The geology.com map lists 2 craters in Finland and one in Sweden but this one Mien in Sweden is not the most well known, at 9km its not the largest, or even the most recerntly discovered one. Here are 5 other ones.

Place Diameter Comment

Siljan 52 km Largest known. Obvious when seen from a hill or viewtower, best view in the northeast.
Dellen 19 km Not easy to see the crater shape from the ground, some advocate its one ancient caldera.
Lockne 7.5 km Good view and quite obvious crater from the western craterwall were road 45 runs.
Granby 3 km
Tvären 2 km

Posted by: Sunspot Jun 10 2006, 09:17 AM

Hmmm that story about the impact in Norway has disappeared from spaceweather.com, I guess it was a hoax.

Posted by: ugordan Jun 10 2006, 11:39 AM

The report is still there, but it's on the page entry for 9 June.

Posted by: Myran Jun 10 2006, 12:01 PM

No hoax, you can see the graphs for the soundboom (top) and impact (bottom) on he graph of http://www.aftenposten.no/viten/article1345940.ece that happened 02.13.25 in the morning.

In addition the impact site have been found on a mountain wall in Reisadalen. The force of the impact was vastly exaggerated in the early reports, the meteorite was in fact a rather small one. But we're still somewhat uncertain if it did break up in midair, that cannot be ruled out yet.

Norwegian only page http://www.aftenposten.no/nyheter/iriks/article1346820.ece.

Posted by: ljk4-1 Jun 10 2006, 12:12 PM

There is already a thread devoted to the Norwegian meteorite here:

http://www.unmannedspaceflight.com/index.php?s=&showtopic=2837&view=findpost&p=57761

Posted by: blobrana Jul 21 2006, 01:28 PM

A BBC Horizon programme puts forward a very persuading case that the http://www.bu.edu/phpbin/news/releases/display.php?id=1073 was not the origin of the desert glass, rather it was formed by an airburst of a much smaller 100 metre sized asteroid.

The airburst generated temperatures similar to the sun, and blew a huge plume of gas out into space. The glass wasn't from a crater or it's ejecta, if a crater is formed at all , but from the fireball that blasted huge areas of the surface.

http://news.bbc.co.uk/2/hi/science/nature/5196362.stm


@Bob Shaw
The program also touched upon the formation of Australites and Indochinites - no crater needed - just a loose rubble pile of an asteroid that air blasted south east Asia. The early humans and species like Gigantopithecus blackii would have been incinerated.