[Prev][Next][Index][Thread]
(meteorobs) Fwd: Leonids from Australia
Forwarded without Detlef's permission. Clear skies,
Lew Gramer
------- Forwarded Message
To: IMO-News mailing list <imo-news@yahoogroups.com>
From: Sirko Molau <molau@informatik.rwth-aachendot de>
Date: Tue, 27 Nov 2001 10:39:06 +0100 (MET)
Subject: [IMO-News] Leonids from Australia (fwd)
Date: Tue, 27 Nov 2001 09:51:26 +0100
From: Detlef Koschny <Detlef.Koschny@esa.int>
Hi all,
The ESA meteor group has witnessed the Leonids from Western Australia, in
the outback about 3 driving hours (with 4WD cars) away from Broome. It
was a very exciting night - after five beautiful clear nights, the night
of the maximum started with about 20 % clouds. The cloud cover became
thicker and thicker, just before midnight it was totally overcast. We
saw the first Leonid fireballs through holes in the clouds - this led to
quite spectacular views, since the clouds were black and basically
unvisible (an unknown experience to a European observer, where there is
always lights to illuminate the clouds...). The highlight was a -2 mag
Leonid which flew about 1 deg just above the Southern horizon, parallel
to the horizon for about 90 degrees!
Miraculously, it slowly but steadily cleared up and one hour after
midnight we had beautiful skies, the Magellanic Clouds were blazing,
Canopus, Sirius and Achernar blinding... The show started with about one
bright Leonid per minute, and with bright I mean -2 mag or brighter. Most
of them had orange-yellow heads and left a blueish-green persistant trail
for a few seconds. Very few ones showed persistent trails for half a
minute or so.
As the number of bright Leonids decreased, the faint ones increased. At
one point I saw five meteors within one second. Not looking at the
detailed recorded numbers, my impression was that the activity was fairly
constant for about three hours. It was definitely less activity than the
1999 Leonids, which we had observed from Spain. This was expected, since
the radiant was always low in the sky from our southerly location.
Our visual observations were reported via satellite phone to Vladimir,
thanks for acting as the coordinator there! We obtained about 200 hours
of video data from five intensified video cameras. Two of the cameras
were equipped with objective gratings and we successfully recorded a
number of meteor spectra, showing both emission and absorption lines. We
measured the electric field of the atmosphere. The signal was converted
to the audio range and recorded on the video tape of our wide angle
camera. While the wide angle camera shows about 200 meteors brighter than
+1 mag, so far we did not see (hear) any correlation between the electric
field and a meteor. Alas, more detailed analysis is required to really
exclude any correlation.
All of us noted that the Australians were very aware of the Leonids, be
it truck driver or sales person. The response of the press was enormous,
we gave many interviews and numerous reports about our activites appeared
in the Western Australian newspapers and on TV.
All in all, it was a phantastic experience. Especially sitting in the
outback, at nighttime temperatures of above 20 deg C, 3 hours away from
civilisation, seeing the Magellanic Clouds and the Southern Cross, was an
experience I will never forget.
Our team was: Andre Knoefel (IMO), Roland Trautner (ESA/Aurora), Joe
Zender (ESA), Detlef Koschny (ESA, IMO). We were accompanied by Grant
Hobson, photographer, and Fiona Adolf, reporter. Special thanks to Greg
Quicke from astrotours, who gave generous local support.
For images and more details check out
http://planetary.so.estec.esadot nl/meteors and navigate to "Leonids01".
Detlef (Laffy) Koschny
----------------------------------------------------------------
Detlef Koschny email: detlef.koschny@esa.int
European Space Agency
ESTEC Sci/SO
Keplerlaan 1 phone: +31-71-565-4828
NL-2201 AZ Noordwijk ZH fax: +31-71-565-4697
----------------------------------------------------------------
------- End of Forwarded Message
The archive and Web site for our list is at http://www.meteorobs.org
If you are interested in complete links on the 2001 LEONIDS, see:
http://www.meteorobs.org/storms.html
To stop getting email from the 'meteorobs' list, use the Web form at:
http://www.meteorobs.org/subscribe.html