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English page: Notice from International Herald Tribune and some e-mails, that reached us meanwhile

This illustration shows the moment, when the meteorite startet its flash above the greenlands night, like it might have looked to the eyes of a watcher out from an aerospace:

First an e-mail, which is dated to 23th of Dec, 1997. We show that, because it contains actually facts and questions about the cloud, that can be seen at the satellite-photos. That cloud and the meteor fall seem to be two different things, that do not depend from each others:

....."Subject: Meteor Nope - Continued
Date: Tue, 23 Dec 97 08:01:32 PST8
The Dec 9, 1997 cloud over Greenland is proving to be an extremly interesting topic. I have been net surfing on this topic and have discovered a number of extremly interesting reports.

First, there was, in fact, a significant meteor fall (a "bollide") over Greenland on 9 Dec, @0821GMT. The Danish government has examined a number of eye witness accounts and a very interesting security camera video tape from a parking lot at Nuuk (64.2N, 51.7W). One of cars in the lot was facing towards the bollide and acted as a partial "whole sky camera." By surveying the location of the security camera and the car, the Danish government and a Czech Republic scientist have determined a high probability ellips centered at 53.2N, 46.5W. The ellipse is 40KM by 120KM, with the long axis being approximately east-west. This is over the Greenland ice cap where the ice is 7,000 to 9,000 feet above sea level, and 12,000 feet thick. The Danish Ice Service is planning an aerial search for 2 January 1998.

The place where the search is now centered is about 150 Nautical Miles (NM) East of where the seismic data (a significant 11 second event) triangulated (63N, 51W). But that is not bad when you consider that some of the seismographs were thousands of miles away.

The search ellips is about 120 NM West of the center of the cloud in the TIROS images. Unfortunately, it seems Danish Meteorologists have reached the conclusion that the cloud is a coincidence for two reasons: 1) They have developed real confidence in the location of the bollide impact to the west, 2) they have identified the previous occurrence of a similar cloud in the same place, albeit much smaller and not nearly as high.

However, the TIROS Channel 3 image does show a dark cloud, even though channel 4 shows a cold cloud. This is similar to a volcanic plume, but the dark data can be explained as liquid water (more on this below). The seimic data precludes a volcanic erruption (volcanoes are not that quick, and a JPL expert on the lunar and Viking seismographs believes the signature is a meteorite). So the if there is no debris from an impact in the cloud, the dark data has to be liquid water. The TIROS Channel 1 image clearly shows shadows indicating a cloud top of at least 24,000 feet. More research on the synoptic situation is needed, but it appears the cloud top was trapped by the tropopause (a very low tropopause, but this is in the arctic). There are obvious orographically triggered clouds to the south that are moving west to east, but the movement of this cloud seems to indicate south to north movement, which means the cloud of interest is much higher, which confirms the tops estimated from the visible shadow. The ridge of the Greenland Ice cap to the West is 9,000 feet MSL, and the mountains along the coast infrequently extend above 5,000 feet. There are numerous sea level fjords extending up to 50 NM inland. So the geography in the area is quite unique. The main air flow is cold dry air moving west to east off the ice cap, with the jet stream well south.

So, what do we need now. We need a mountain wave(standing wave) expert who can explain this event. The cloud is very dense, and appears to be almost convective, and it has to contain liquid water to explain the channel 3 image (in channel 3, 3.6 microns, liquid water radiates very differently from ice crystals). The cloud physics involved must be very interesting because carrying super cooled liquid water to 24,000 feet in the arctic sounds like a remarkable feat to me. Anyone out there want to take a shot at this? Is there a Masters thesis in this somewhere? Or, is it possible that there is still a connection between this cloud and the bollide impact?

Sorry for the long message, but this whole situation is really interesting to me."....

name and e-mail-adress is known to us

*

Noaa-14-pic, visibility light, from December, 9 th, 1997, 14:24 h UTC:

THE HUNT FOR METEOR IS ON IN GREENLAND

(By Malcom W. Browne, New York Times Service)

NEW YORK -- In the dead of the Arctic night on Dec. 9, flashes of light as bright as nuclear blasts lighted up the southern tip of Greenland, and Danish scientists have begun a search for what they believe was a gigantic meteor impact.

News of the huge fireball was reported this week in an e-mail message from the Niels Bohr Institute in Copenhagen. The dazzling flashes at 5:11 A.M. Greenland time were observed by the crews of three widely separated Scandinavian trawlers operating near the Greenland coast. A few minutes later seismic signals believed to be from the general area were detected by stations in Norway, Finland and Germany.

Based on observations by the three trawler crews, experts at the Bohr Institute, the Tycho Brahe Planetarium, the Copenhagen Astronomical Society and other Danish scientific institutions estimated that the main impact area for the presumably fragmented meteor was at about 61 degrees 25 minutes north latitude and 44 degrees 26 minutes west longitude. This is on the Greenland ice cap about 50 kilometers northeast of the coastal airport of Narsarsuag.

The Bohr Institute reported: ``The flashes ovserved in conjunction with the meteorite were so bright as to turn night into daylight at a distance of 100 kilometers, and can be compared to the light of a nuclear explosion in the atmosphere. However, we stress that there is no reason to believe it was caused by other than natural causes.'' Meteor impacts of that size are extremely rare.

The seismic signals picked up in Europe did not enable the scinetists to determine the exact location fo the impact, but the Danish team hopes that an analysis of seismic records from Canada and othere parts of the world will help.

The scientists plan to send a reconaissance plane over the area when weather permits, but the prospect of spotting the impact from the air is uncertain. At this time of year Greenland is in darkness for most of each day, and snow falls almost constantly. Up to 40 inches may have fallen over the areo since Dec. 9.

But two radar-equipped European Space Agency satellites, ERS1 and ERS2 are being programmed to look for the impact site from space, Radar could detect large depressions in the ice cap marking the resting place of large meteoric fragments. By summer, when a search by ground teams becomes practical, smaller meteorite fragments are likely to be buried by more than three meters of snow, but large chunks might still be detectable.

Scientists are eager to recover fragments of the meteorite because of clues it may contain about the early history of the solar system. Because of the brilliance of the flash, Danish scientists said ``the event can in size probably be compared to the Cape York meteorite that fell in prehistoric times in Melville Bay south of Thule, Greenland.'' Some 50 tons of iron meteorites were recovered from the Cape York impact site.

One of them, the 34-ton Ahnighito meteorite, is the largest ever pulled from the ground; since 1935 it has been on display at the American Museum of Natural History in New York City.

Since scientists have not reached the site of the latest impact they have not recovered debris and therefore do not know whether the huge projectile was a meteor or a small comet. Both are capable of causing immense destruction.

The most destructive impact of the century occured on June 30, 1908, when a blinding flash in the sky near the Tunguska River in Siberia flattened more tha 2,000 square kilometers of forest.

END OF THIS paper-text

Following more Informations that reached us by e-mail:

QAQORTOQ METEORITE FALL, GREENLAND

It appears that an enormous meteorite has fallen over the southern part of the Greenland Ice cap. The event was witnessed by people on the west coast of Greenland, and by fishermen off shore. Further records come from seismic data, weather satellites, and a video camera at Nuuk.

The event occurred on December 9, at 08:21 UTC. At this moment, local solar time was 05:21 A.M. According to reports, the sky was clear.

SEISMIC DATA

Seismic records show a very special event. It lasts more than 10 seconds, indicating a time extended source. It is a high-frequency event, reminiscent of the Lunar meteorite seismic records made by the Apollo missions. This makes phase correlation, hence localization, difficult, but initial indication is that the event occurred in Greenland.

VIDEO

A parking lot video surveillence camera in Nuuk, capital of Greenland (64 North, 51 West), recorded an extremely bright flash of light from a moving source. One the footage shown on Danish TV, the event lasted about 2 seconds. However, the time compression factor was not reported.

WEATHER SATELLITE IMAGING

At least two weather satellites show the dramatic development of a cloud system near 63 degrees North 45 degrees West. The clearest images can be obtained from a polar orbiting satellite monitored at the Dundee Satellite Receiving station. One set of multicolor images show a dark cloud 120 km across, on December 9 14:24 UTC Channel 3 The cloud is still visible 26 hours later, at which moment one can see a 100 km long dark line on the Ice Cap, marking the western edge of the cloud. The line points some 10 degrees West of North, which we interpret as the arrival direction of the meteoroid.

The cloud height has been estimated by the Tycho Brahe Planetarium to be 6 - 8 km (based on the shadow cast). The enclosed volume of air is thus at least 50,000 cubic km. If the moist air contains 0.1 gram of water per litre derived either from the meteoroid or from evaporating ice, this amounts to 5 billion tons. The minimum meteorite mass required to melt and evaporate this amount of water is 4 million tons, if the velocity of the impactor was 70 km per second.

SEARCH PARTY

According to Danish TV (DR1 and TV2 text-tv), a search mission is being planned by the ice service at Narssaq.

THE NAME

Old tradition dictates that a fall is named from the closest postal office.This is Qaqortoq, at the south tip of Greenland. The city was formerly called Julianehaab.

The above report was compiled using data supplied by Morten Bo Madsen, Anja Andersen, Torben Risbo, and Lars Lindberg Christensen. For further information, call or write:

Holger Pedersen
NBIfAFG
Copenhagen University Observatory
Juliane Maries Vej 30
DK-2100 Copenhagen OE
Denmark
e-mail holger@astro.ku.dk
http://www.astro.ku.dk/~holger/
phone (45) 3532 5980 To the top
Last revision: December 13, 1997
Note: information contained here is not an official product of Copenhagen University.

Press statement
by
Niels Bohr Institute, Geophysical Dept.
971215 20.00UT

A big meteor impact has probably occurred in Southern Greenland at 61 25N, 44 26W on Tuesday, December 9th app. 08.11UTC (05.11am local time). The position is on the ice cap app. 50 kilometers NE of Narsarsuaq Airport.

The position has been determined on the basis of observations made by a Danish and a Norwegian trawler near the east coast of Greenland, and a Danish trawler at a position in the bay off Julianehaab. Based on fairly accurate direction findings and the fact, that the trawlers were situated on both sides of Southern Greenland it can be determined, that the meteorite fell on land.

The relevant trawlers are:

Halten Trawl, Norwegian at 62 05N, 41 10W
Regina C, Danish at 60 55N, 51 35W
Timmarut, Danish at 60 13N, 46 43W

Observations of the satelite lighttrack from Nuuk indicates that the meteorite passed a bit south of Nuuk in southeasterly direction towards the mentioned impact site in Southern Greenland.

Seismic disturbances have been observed on Svalbard and Finmarka (Norway). These tremors are observed at 08.21UTC and 08.23UTC and are assumed to relate to the impact or the passage of the meteorite through the atmosphere. The signals did not allow a seismic localization of the event. The observations are made by NORSAR (Norwegian Seismic Array), Kjeller, Norway. Fainter signals were observed in Finland and Germany. The seismic stations in Greenland (Sonder Stromfjord and Danmarkshavn) has no observations. Further seismic data will be collected from Iceland and Canada in order to confirm the visual localization.

Observations from the satellites ERS1 and ERS2 are being planned. These satellites observe the surface of the Earth using radar.

The flashes observed in conjunction with the meteorite were so bright as to turn night into daylight at a distance of 100 kilometers and can be compared to the light af a nuclear explosion in the atmosphere. However, we stress that there is no reason to belive other than natural causes.

During the day, the position will be overflown by an ice reconnaissance plane, from the Ice Central in Narsarsuaq on its planned flight from Kap Farvel to Nuuk.

The event can in size probably be compared to the Kap York meteorite, that in prehistoric time fell in Melville Bay, Sassivik south of Thule. Findings from the meteorite consist of a number of iron meteorites totalling 50 tons. One of these ironfragments can be seen in Copenhagen outside the Geological Museum.

Collecting and studying material from this meteorite has great scientific value. It is fortunate that the meteorite fell on land, but a search on the ice cap is difficult and in winter impeded by bad weather and darkness. Since December 9th 30-100cm of snow has fallen in the area and before summer smaller fragments will be covered by 3 meters of snow. According to Danish law, findings of meteorite material must be turned over to the authorities, in this case they will be the property of the Greenland Home Rule.

These investigations are coordinated by Geophysical Dept. at the Niels Bohr Institute, University of Copenhagen in cooperation with:

Tycho Brahe Planetarium, Copenhagen.
Copenhagen Astronomical Society
National Survey and Cadastre, Denmark
NORSAR, Kjeller, Norway
Danish Center for Remote Sensing, Technical University of Denmark

The information may be qouted, if the source is indicated.

Notice: More information about the meteorite fall of greenland you can get by the internet-adress: "http://www.astro.ku.dk/~holger" there all the news are documented in a better englisch, than we are able to write...

we thank you for your visit

© by Jürgen Vollmer, Marburg, 1998

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