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Potsdam - Germany, 19 - 22 September 1991

  • 10th meeting

  • Local organizers: Jürgen Rendtel, Rainer Arlt (Arbeitskreis Meteore).

  • 36 participants from 7 countries: Belgium (4), Czech Republic (1), Germany (21), Russia (3), the Netherlands (2), Slovakia (4) and U.K. (1).

  • 25 presentations (15 lectures, 10 posters) of which 19 featured in the Proceedings.

  • IMC 1991 Proceedings (ISBN 978-2-87355-001-1): 90 pages (eds. Jürgen Rendtel, Rainer Arlt).

  • Contents: visual plotting accuracy, shower association - meteor simulations, plotting errors - telescopic plotting accuracy - meteor trains - Taurid complex - meteoroid distribution - fireballs.

  • Participation fee 90 Euro.

When the 1991 IMC was planned, Germany was still split up between the B.R.D. and the D.D.R., but by the time it took place, both had merged into a reunified Germany, which explains why the IMC apparently happened in the same country in successive years. The location was at an hotel, a former youth hostel, at Lake Schwielowsee. This event suffered from a lack of publicity for the meeting, but despite the smaller number of people, the number of topics and lectures was impressive. The poster session was integrated into the program for the first time. The excursion featured a trip on an old ship (built in 1878) from Lake Schwielowsee to Potsdam that allowed a visit to the Astronomical Observatory of Potsdam with its Einsteinturm Solar Observatory, and the large dome of the Nikolai church in Potsdam. For the first time a barbecue was organized at an IMC on Saturday evening which proved a most enjoyable way for informal chats with old and new friends.

Acknowledgement: We thank Marc de Lignie, Axel Haas and Casper ter Kuile for providing photographs for this overview of the 1991 IMC.

Memorial: Gennadij Vasiljevich Andreev, born 13 August 1950 died unexpectedly on 14 September 2002, asteroid 1983 RX2 was named after him as N4199 Andreev, he was a very enthousiastic lecturer and organizer of several Tunguska expeditions. High resolution versions can be obtained on request for the images in the gallery.

The Proceedings of the International Meteor Conference, Potsdam 1991. The Proceedings of the International Meteor Conference, Potsdam 1991.

The hotel at Lake Schwielowsee where the 1991 IMC took place (credit Axel Haas). The hotel at Lake Schwielowsee where the 1991 IMC took place (credit Axel Haas).

The hotel at Lake Schwielowsee where the 1991 IMC took place (credit Marc de Lignie). The hotel at Lake Schwielowsee where the 1991 IMC took place (credit Marc de Lignie).

The Trabants served as transport vehicles at the 1991 IMC (credit Axel Haas). The Trabants served as transport vehicles at the 1991 IMC (credit Axel Haas).

Ina Rendtel as IMC taxi-driver (credit Axel Haas). Ina Rendtel as IMC taxi-driver (credit Axel Haas).

An IMC when times were changing, statues of Lenin became history (credit Marc de Lignie). An IMC when times were changing, statues of Lenin became history (credit Marc de Lignie).

Peter Aneca, Marc de Lignie, Cis Verbeeck and André Knöfel (credit Axel Haas). Peter Aneca, Marc de Lignie, Cis Verbeeck and André Knöfel (credit Axel Haas).

Peter Zimnikoval arrived in the rooms of the residents (credit Marc de Lignie). Peter Zimnikoval arrived in the rooms of the residents (credit Marc de Lignie).

Casper ter Kuile photographing Peter Aneca, Mirko Nitschke and Kathrin Düber (credit Axel Haas). Casper ter Kuile photographing Peter Aneca, Mirko Nitschke and Kathrin Düber (credit Axel Haas).

Marc de Lignie presenting 'The Perseid radiant as found from double-station photographic observations' (credit Casper ter Kuile). Marc de Lignie presenting 'The Perseid radiant as found from double-station photographic observations' (credit Casper ter Kuile).

Marc de Lignie presenting 'The Perseid radiant as found from double-station photographic observations' (credit Paul Roggemans). Marc de Lignie presenting 'The Perseid radiant as found from double-station photographic observations' (credit Paul Roggemans).

Petr Pravec presenting 'Perseids telescopically and by means of a TC-camera' (credit Casper ter Kuile). Petr Pravec presenting 'Perseids telescopically and by means of a TC-camera' (credit Casper ter Kuile).

Petr Pravec presenting 'Perseids telescopically and by means of a TC-camera' (credit Marc de Lignie). Petr Pravec presenting 'Perseids telescopically and by means of a TC-camera' (credit Marc de Lignie).

Petr Pravec presenting 'Perseids telescopically and by means of a TC-camera' (credit Marc de Lignie). Petr Pravec presenting 'Perseids telescopically and by means of a TC-camera' (credit Marc de Lignie).

Oleg Bel'kovich presenting 'Processing of visual observations and results' (credit Axel Haas). Oleg Bel'kovich presenting 'Processing of visual observations and results' (credit Axel Haas).

Oleg Bel'kovich presenting 'Processing of visual observations and results' (credit Casper ter Kuile). Oleg Bel'kovich presenting 'Processing of visual observations and results' (credit Casper ter Kuile).

Oleg Bel'kovich presenting 'Processing of visual observations and results' (credit Axel Haas). Oleg Bel'kovich presenting 'Processing of visual observations and results' (credit Axel Haas).

Ralf Koschack and Oleg Bel'kovich (credit Casper ter Kuile). Ralf Koschack and Oleg Bel'kovich (credit Casper ter Kuile).

Malcolm Currie, Ralf Koschack and Oleg Bel'kovich (credit Casper ter Kuile). Malcolm Currie, Ralf Koschack and Oleg Bel'kovich (credit Casper ter Kuile).

Ralf Koschack, Oleg Bel'kovich, Alexandra Terentjeva, Cis Verbeeck and Marc Gyssens (credit Axel Haas). Ralf Koschack, Oleg Bel'kovich, Alexandra Terentjeva, Cis Verbeeck and Marc Gyssens (credit Axel Haas).

Session chairman Malcolm Currie and Gennadij Andreev presenting 'The Leonid Meteor Stream spatial structure' (credit Paul Roggemans). Session chairman Malcolm Currie and Gennadij Andreev presenting 'The Leonid Meteor Stream spatial structure' (credit Paul Roggemans).

Mark Vints presenting 'Telescopic meteors - train observations' (credit Casper ter Kuile). Mark Vints presenting 'Telescopic meteors - train observations' (credit Casper ter Kuile).

Mark Vints presenting 'Telescopic meteors - train observations' (credit Paul Roggemans). Mark Vints presenting 'Telescopic meteors - train observations' (credit Paul Roggemans).

Ralf Koschack presenting 'Plotting errors and consequences for shower association of visual meteors' (credit Casper ter Kuile). Ralf Koschack presenting 'Plotting errors and consequences for shower association of visual meteors' (credit Casper ter Kuile).

Roland Egger presenting 'Determination of meteor positions - methods and simulation' (credit Casper ter Kuile). Roland Egger presenting 'Determination of meteor positions - methods and simulation' (credit Casper ter Kuile).

Free chat in the evening, at left Roland Egger, in the back Ulrich Sperberg, Pierre Bader, Hans-Georg Schmidt, André Knöfel at right and in front Ralf Koschack (credit Axel Haas). Free chat in the evening, at left Roland Egger, in the back Ulrich Sperberg, Pierre Bader, Hans-Georg Schmidt, André Knöfel at right and in front Ralf Koschack (credit Axel Haas).

Mirko Nitschke presenting 'Computer aided meteor observations', session chairman Hans-Georg Schmidt at left (credit Casper ter Kuile). Mirko Nitschke presenting 'Computer aided meteor observations', session chairman Hans-Georg Schmidt at left (credit Casper ter Kuile).

Jürgen Rendtel presenting 'Report from the Asteroids, Comets, Meteors 91 Conference' (credit Casper ter Kuile). Jürgen Rendtel presenting 'Report from the Asteroids, Comets, Meteors 91 Conference' (credit Casper ter Kuile).

Jürgen Rendtel presenting 'Report from the Asteroids, Comets, Meteors 91 Conference' (credit Marc de Lignie). Jürgen Rendtel presenting 'Report from the Asteroids, Comets, Meteors 91 Conference' (credit Marc de Lignie).

Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Axel Haas). Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Axel Haas).

Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Casper ter Kuile). Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Casper ter Kuile).

Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Marc de Lignie). Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Marc de Lignie).

The audience from l.to r. Gennadij Andreev, Alexandra Terentjeva and Oleg Bel'kovic (credit Axel Haas). The audience from l.to r. Gennadij Andreev, Alexandra Terentjeva and Oleg Bel'kovic (credit Axel Haas).

Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Marc de Lignie). Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Marc de Lignie).

Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Marc de Lignie). Gennadij Andreev presenting 'The second international Tunguska expedition' (credit Marc de Lignie).

The audience with in front from l.to r. André Knöfel, Cis Verbeeck showing photographs to Casper ter Kuile, Rainer Arlt, Ralf Koschack (in front), Alexandra Terentjeva (background), Jaroslav Gerbos (background), Pierre Bader, Malcolm Currie (front), Jürgen Rendtel (partly hidden), ??, Petr Pravec, ??, Marc de Lignie and ?? (credit Axel Haas). The audience with in front from l.to r. André Knöfel, Cis Verbeeck showing photographs to Casper ter Kuile, Rainer Arlt, Ralf Koschack (in front), Alexandra Terentjeva (background), Jaroslav Gerbos (background), Pierre Bader, Malcolm Currie (front), Jürgen Rendtel (partly hidden), ??, Petr Pravec, ??, Marc de Lignie and ?? (credit Axel Haas).

The audience with in front from l.to r. Peter Zimnikoval, Daniel Ocenas, Jürgen Rendtel and Jaroslav Gerbos (credit Axel Haas). The audience with in front from l.to r. Peter Zimnikoval, Daniel Ocenas, Jürgen Rendtel and Jaroslav Gerbos (credit Axel Haas).

From l.to r. Casper ter Kuile, Peter Aneca, Kathrin Düber and Mirko Nitschke (credit Axel Haas). From l.to r. Casper ter Kuile, Peter Aneca, Kathrin Düber and Mirko Nitschke (credit Axel Haas).

Looking at the results on a PC (credit Casper ter Kuile). Looking at the results on a PC (credit Casper ter Kuile).

From l.to r. Cis Verbeeck, Marc de Lignie, Rainer Arlt and Malcolm Currie (credit Axel Haas). From l.to r. Cis Verbeeck, Marc de Lignie, Rainer Arlt and Malcolm Currie (credit Axel Haas).

From l.to r. Torsten Hansen, Ralf Koschack, Rainer Arlt and Stefan Ströbele (credit Casper ter Kuile). From l.to r. Torsten Hansen, Ralf Koschack, Rainer Arlt and Stefan Ströbele (credit Casper ter Kuile).

From l.to r. Torsten Hansen, Ralf Koschack, Rainer Arlt and Stefan Ströbele (credit Marc de Lignie). From l.to r. Torsten Hansen, Ralf Koschack, Rainer Arlt and Stefan Ströbele (credit Marc de Lignie).

From l.to r. Stefan Ströbele (front), Malcolm Currie, Jürgen Rendtel, Mark Vints and Petr Pravec talking to Marc Gyssens (credit Axel Haas). From l.to r. Stefan Ströbele (front), Malcolm Currie, Jürgen Rendtel, Mark Vints and Petr Pravec talking to Marc Gyssens (credit Axel Haas).

Casper ter Kuile at the poster session (credit Casper ter Kuile). Casper ter Kuile at the poster session (credit Casper ter Kuile).

From l.to r. Marc de Lignie making a photo of Casper ter Kuile and Mark Vints (credit Axel Haas). From l.to r. Marc de Lignie making a photo of Casper ter Kuile and Mark Vints (credit Axel Haas).

Ina Rendtel selling IMO publications and Petr Pravec taking a look (credit Casper ter Kuile). Ina Rendtel selling IMO publications and Petr Pravec taking a look (credit Casper ter Kuile).

Ina Rendtel selling IMO publications with from l.to r. Ulrich Sperberg, Peter Zimnikoval, Daniel Ocenas and Paul Roggemans (credit Casper ter Kuile). Ina Rendtel selling IMO publications with from l.to r. Ulrich Sperberg, Peter Zimnikoval, Daniel Ocenas and Paul Roggemans (credit Casper ter Kuile).

Axel Haas and Peter Zimnikoval at the IMO bookshop (credit Marc de Lignie). Axel Haas and Peter Zimnikoval at the IMO bookshop (credit Marc de Lignie).

Lunch at the 1991 IMC, Malcolm Currie and Marc de Lignie (credit Casper ter Kuile). Lunch at the 1991 IMC, Malcolm Currie and Marc de Lignie (credit Casper ter Kuile).

Lunch at the 1991 IMC, from l. to r. Pierre Bader, Ragnar Bödefeld, Roland Egger, Roland Winkler, Mark Vints, ??, Siegfried Stapf and Stefan Ströbele (credit Casper ter Kuile). Lunch at the 1991 IMC, from l. to r. Pierre Bader, Ragnar Bödefeld, Roland Egger, Roland Winkler, Mark Vints, ??, Siegfried Stapf and Stefan Ströbele (credit Casper ter Kuile).

Lunch at the 1991 IMC, from l. to r. ??, Ralf Koschack, Genadij Andreev, Oleg Bel'kovich, Alexandra Terentjev, a waitress, Kathrin Düber and ?? (credit Casper ter Kuile). Lunch at the 1991 IMC, from l. to r. ??, Ralf Koschack, Genadij Andreev, Oleg Bel'kovich, Alexandra Terentjev, a waitress, Kathrin Düber and ?? (credit Casper ter Kuile).

Lunch at the 1991 IMC, from l.to r. Roland Egger, Jürgen Rendtel, Ina Rendtel, Paul Roggemans, André Knöfel (back), Axel Haas (back), Stefan Ströbele (back) and Irmgard Schmidt (back) (credit Casper ter Kuile). Lunch at the 1991 IMC, from l.to r. Roland Egger, Jürgen Rendtel, Ina Rendtel, Paul Roggemans, André Knöfel (back), Axel Haas (back), Stefan Ströbele (back) and Irmgard Schmidt (back) (credit Casper ter Kuile).

Ready to leave for the saturday afternoon excursion (credit Casper ter Kuile). Ready to leave for the saturday afternoon excursion (credit Casper ter Kuile).

One of the oldest ships still in use, ready to take the IMC participants to Potsdam (credit Axel Haas). One of the oldest ships still in use, ready to take the IMC participants to Potsdam (credit Axel Haas).

On the ship in the middle we recognize Peter Aneca and Malcolm Currie (credit Casper ter Kuile). On the ship in the middle we recognize Peter Aneca and Malcolm Currie (credit Casper ter Kuile).

On the ship from l.to r. André Knöfel, Roland Egger and Mirko Nitschke (credit Paul Roggemans). On the ship from l.to r. André Knöfel, Roland Egger and Mirko Nitschke (credit Paul Roggemans).

A look over the water on the hotel where the IMC took place (credit Axel Haas). A look over the water on the hotel where the IMC took place (credit Axel Haas).

On the ship IMC from l.to r. Jürgen Rendtel, Oleg Bel'kovich, Casper ter Kuile, a non participant and Alexandra Terentjeva (credit Marc de Lignie). On the ship IMC from l.to r. Jürgen Rendtel, Oleg Bel'kovich, Casper ter Kuile, a non participant and Alexandra Terentjeva (credit Marc de Lignie).

On the ship in the middle we recognize Irmgard Schmidt and Jürgen Rendtel (credit Casper ter Kuile). On the ship in the middle we recognize Irmgard Schmidt and Jürgen Rendtel (credit Casper ter Kuile).

On the ship IMC participants enjoy the excellent weather (credit Paul Roggemans). On the ship IMC participants enjoy the excellent weather (credit Paul Roggemans).

Roland Egger (credit Axel Haas). Roland Egger (credit Axel Haas).

On the ship IMC from l.to r. Gennadij Andreev, Oleg Bel'kovich, a non participant, Alexandra Terentjeva, Casper ter Kuile and Jürgen Rendtel (credit Marc de Lignie). On the ship IMC from l.to r. Gennadij Andreev, Oleg Bel'kovich, a non participant, Alexandra Terentjeva, Casper ter Kuile and Jürgen Rendtel (credit Marc de Lignie).

On the ship IMC from l.to r. Gennadij Andreev, Oleg Bel'kovich, a non participant and Alexandra Terentjeva (credit Paul Roggemans). On the ship IMC from l.to r. Gennadij Andreev, Oleg Bel'kovich, a non participant and Alexandra Terentjeva (credit Paul Roggemans).

Malcolm Currie (credit Axel Haas). Malcolm Currie (credit Axel Haas).

On the ship IMC from l.to r. Alexandra Terentjeva, Irmgard Schmidt (back), Ina Rendtel (back), Axel Haas (front), André Knöfel and Malcolm Currie (credit Paul Roggemans). On the ship IMC from l.to r. Alexandra Terentjeva, Irmgard Schmidt (back), Ina Rendtel (back), Axel Haas (front), André Knöfel and Malcolm Currie (credit Paul Roggemans).

Alexandra Terentjeva (credit Axel Haas). Alexandra Terentjeva (credit Axel Haas).

On the ship IMC from l.to r. Mirko Nitschke, Rainer Arlt and Kathrin Düber (credit Axel Haas). On the ship IMC from l.to r. Mirko Nitschke, Rainer Arlt and Kathrin Düber (credit Axel Haas).

Casper ter Kuile (credit Axel Haas). Casper ter Kuile (credit Axel Haas).

Mirko Nitschke (credit Paul Roggemans). Mirko Nitschke (credit Paul Roggemans).

Arrival in Potsdam near the St Nikolai Church (credit Axel Haas). Arrival in Potsdam near the St Nikolai Church (credit Axel Haas).

The Einsteinturm Solar observatory (credit Axel Haas). The Einsteinturm Solar observatory (credit Axel Haas).

The Einsteinturm Solar observatory (credit Paul Roggemans). The Einsteinturm Solar observatory (credit Paul Roggemans).

IMC visitors at the Einsteinturm Solar observatory (credit Axel Haas). IMC visitors at the Einsteinturm Solar observatory (credit Axel Haas).

IMC visitors at the Einsteinturm Solar observatory (credit Marc de Lignie). IMC visitors at the Einsteinturm Solar observatory (credit Marc de Lignie).

The Einsteinturm Solar observatory (credit Paul Roggemans). The Einsteinturm Solar observatory (credit Paul Roggemans).

The optics on the top of the Einsteinturm Solar observatory (credit Axel Haas). The optics on the top of the Einsteinturm Solar observatory (credit Axel Haas).

Inside the building of the Einsteinturm Solar observatory (credit Casper ter Kuile). Inside the building of the Einsteinturm Solar observatory (credit Casper ter Kuile).

Preparing for the group photo at the Einsteinturm Solar observatory (credit Axel Haas). Preparing for the group photo at the Einsteinturm Solar observatory (credit Axel Haas).

Preparing for the group photo at the Einsteinturm Solar observatory. From l.to r. Ralf Koschack, Siegfried Stapf, Stefan Ströbele, Marc Gyssens (seated), Peter Aneca (?), Irmgard Schmidt, Pierre Bader (seated), Rainer Arlt (seated partly hidden), Hans-Georg Schmidt (looking away), Kathrin Düber (hidden), Ina Rendtel, Marc de Lignie (seated), Ragnar Bödefeld (partly hidden), Alexandra Terentjeva, Ulrich Sperberg, Mark Vints (hidden), Paul Roggemans, Cis Verbeeck, Peter Zimnikoval (partly hidden), Mirko Nitschke, Malcolm Currie (front), Gennadij Andreev (hidden), Jaroslav Gerbos, Oleg Belkovich, Daniel Ocenas (hidden) and André Knöfel (top right) (credit Axel Haas). Preparing for the group photo at the Einsteinturm Solar observatory. From l.to r. Ralf Koschack, Siegfried Stapf, Stefan Ströbele, Marc Gyssens (seated), Peter Aneca (?), Irmgard Schmidt, Pierre Bader (seated), Rainer Arlt (seated partly hidden), Hans-Georg Schmidt (looking away), Kathrin Düber (hidden), Ina Rendtel, Marc de Lignie (seated), Ragnar Bödefeld (partly hidden), Alexandra Terentjeva, Ulrich Sperberg, Mark Vints (hidden), Paul Roggemans, Cis Verbeeck, Peter Zimnikoval (partly hidden), Mirko Nitschke, Malcolm Currie (front), Gennadij Andreev (hidden), Jaroslav Gerbos, Oleg Belkovich, Daniel Ocenas (hidden) and André Knöfel (top right) (credit Axel Haas).

The IMC 1991 group photo in front of the Einsteinturm Solar observatory, seated from l.to r. Ralf Koschack, Marc Gyssens, Rainer Arlt, Pierre Bader and Malcolm Currie. Standing from l.to r. Siegfried Stapf, Jürgen Rendtel, ??, Kathrin Düber, Irmgard Schmidt, Mark Vints, Hans-Georg Schmidt, Ragnar Bödefeld, Ina Rendtel, André Knöfel, Paul Roggemans, Mirko Nitschke, Ulrich Sperberg, Axel Haas, Roland Egger, Oleg Bel'kovich, Alexandra Terentjeva, Gennadij Andreev, Cis Verbeeck, Petr Pravec, Peter Zimnikoval, Peter Aneca, Daniel Ocenas, Jarislav Gerbos and ?? (credit Marc de Lignie). The IMC 1991 group photo in front of the Einsteinturm Solar observatory, seated from l.to r. Ralf Koschack, Marc Gyssens, Rainer Arlt, Pierre Bader and Malcolm Currie. Standing from l.to r. Siegfried Stapf, Jürgen Rendtel, ??, Kathrin Düber, Irmgard Schmidt, Mark Vints, Hans-Georg Schmidt, Ragnar Bödefeld, Ina Rendtel, André Knöfel, Paul Roggemans, Mirko Nitschke, Ulrich Sperberg, Axel Haas, Roland Egger, Oleg Bel'kovich, Alexandra Terentjeva, Gennadij Andreev, Cis Verbeeck, Petr Pravec, Peter Zimnikoval, Peter Aneca, Daniel Ocenas, Jarislav Gerbos and ?? (credit Marc de Lignie).

The IMC 1991 group photo in front of the Einsteinturm Solar observatory (credit Casper ter Kuile). The IMC 1991 group photo in front of the Einsteinturm Solar observatory (credit Casper ter Kuile).

The IMC 1991 group photo in front of the Einsteinturm Solar observatory, seated from l.to r. Ralf Koschack, Marc Gyssens, Rainer Arlt, Pierre Bader and Malcolm Currie. Standing from l.to r. Siegfried Stapf, Jürgen Rendtel, ??, Kathrin Düber, Irmgard Schmidt, Mark Vints, Hans-Georg Schmidt, Ragnar Bödefeld, Ina Rendtel, André Knöfel, Paul Roggemans, Mirko Nitschke, Ulrich Sperberg, Axel Haas, Roland Egger, Oleg Bel'kovich, Alexandra Terentjeva, Gennadij Andreev, Cis Verbeeck, Petr Pravec, Peter Zimnikoval, Peter Aneca, Daniel Ocenas, ?? and Jarislav Gerbos (credit Marc de Lignie). The IMC 1991 group photo in front of the Einsteinturm Solar observatory, seated from l.to r. Ralf Koschack, Marc Gyssens, Rainer Arlt, Pierre Bader and Malcolm Currie. Standing from l.to r. Siegfried Stapf, Jürgen Rendtel, ??, Kathrin Düber, Irmgard Schmidt, Mark Vints, Hans-Georg Schmidt, Ragnar Bödefeld, Ina Rendtel, André Knöfel, Paul Roggemans, Mirko Nitschke, Ulrich Sperberg, Axel Haas, Roland Egger, Oleg Bel'kovich, Alexandra Terentjeva, Gennadij Andreev, Cis Verbeeck, Petr Pravec, Peter Zimnikoval, Peter Aneca, Daniel Ocenas, ?? and Jarislav Gerbos (credit Marc de Lignie).

The IMC 1991 group photo in front of the Einsteinturm Solar observatory, seated from l. to r. Casper ter Kuile, Marc de Lignie, Marc Gyssens, Rainer Arlt, Pierre Bader and Malcolm Currie. Standing from l.to r. Stefan Ströbele, Siegfried Stapf, Ralf Koschack, Jürgen Rendtel, ??, Kathrin Düber, Irmgard Schmidt, Hans-Georg Schmidt, Mark Vints, Ina Rendtel, Ragnar Bödefeld, Alexandra Terentjeva, Axel Haas, Oleg Bel'kovich, André Knöfel, Gennadij Andreev, Cis Verbeeck, Peter Zimnikoval, Roland Egger, Daniel Ocenas, Peter Aneca, Jarislav Gerbos, Petr Pravec, ?? and Roland Winkler (credit Paul Roggemans). The IMC 1991 group photo in front of the Einsteinturm Solar observatory, seated from l. to r. Casper ter Kuile, Marc de Lignie, Marc Gyssens, Rainer Arlt, Pierre Bader and Malcolm Currie. Standing from l.to r. Stefan Ströbele, Siegfried Stapf, Ralf Koschack, Jürgen Rendtel, ??, Kathrin Düber, Irmgard Schmidt, Hans-Georg Schmidt, Mark Vints, Ina Rendtel, Ragnar Bödefeld, Alexandra Terentjeva, Axel Haas, Oleg Bel'kovich, André Knöfel, Gennadij Andreev, Cis Verbeeck, Peter Zimnikoval, Roland Egger, Daniel Ocenas, Peter Aneca, Jarislav Gerbos, Petr Pravec, ?? and Roland Winkler (credit Paul Roggemans).

The IMC group visiting the observatory of Potsdam (credit Marc de Lignie). The IMC group visiting the observatory of Potsdam (credit Marc de Lignie).

Relaxing in the parc of the observatory, from l.to r. Marc de Lignie, Jaroslav Gerbos, Ulrich Sperberg, Daniel Ocenas, Peter Zimnikoval, Gennadij Andreev, Oleg Bel'kovich, Alexandra Terentjeva and Malcolm Currie (credit Casper ter Kuile). Relaxing in the parc of the observatory, from l.to r. Marc de Lignie, Jaroslav Gerbos, Ulrich Sperberg, Daniel Ocenas, Peter Zimnikoval, Gennadij Andreev, Oleg Bel'kovich, Alexandra Terentjeva and Malcolm Currie (credit Casper ter Kuile).

Peter Zimnikoval, Gennadij Andreev, Oleg Bel'kovich and Alexandra Terentjeva (credit Marc de Lignie). Peter Zimnikoval, Gennadij Andreev, Oleg Bel'kovich and Alexandra Terentjeva (credit Marc de Lignie).

Jürgen Rendtel guiding through the observatory parc, from l.to r.Daniel Ocenas, Mark Vints, Jaroslav Gerbos, Petr Pravec, Ragnar Bödefeld, someone hidden, Ulrich Sperberg, Paul Roggemans, Jürgen Rendtel explaining, Cis Verbeeck, Alexandra Terentjeva, Roland Egger, Gennadij Andreev (partly hidden), Oleg Bel'kovich, Mirko Nitschke, Pierre Bader, Someone hidden, Casper ter Kuile, Peter Aneca (partly hidden), Kathrin Drüber (hidden), Hans-Georg Schmidt, ?? and Marc de Lignie (credit Axel Haas). Jürgen Rendtel guiding through the observatory parc, from l.to r.Daniel Ocenas, Mark Vints, Jaroslav Gerbos, Petr Pravec, Ragnar Bödefeld, someone hidden, Ulrich Sperberg, Paul Roggemans, Jürgen Rendtel explaining, Cis Verbeeck, Alexandra Terentjeva, Roland Egger, Gennadij Andreev (partly hidden), Oleg Bel'kovich, Mirko Nitschke, Pierre Bader, Someone hidden, Casper ter Kuile, Peter Aneca (partly hidden), Kathrin Drüber (hidden), Hans-Georg Schmidt, ?? and Marc de Lignie (credit Axel Haas).

From l. to r. Daniel Ocenas, Jürgen Rendtel, Malcolm Currie, Mark Vints, Gennadij Andreev, Jaroslav Gerbos, Peter Zimnikoval, Mirko Nitschke, Ralf Koschack, Kathrin Düber (hidden), Casper ter Kuile, ?? and Cis Verbeeck (credit Marc de Lignie). From l. to r. Daniel Ocenas, Jürgen Rendtel, Malcolm Currie, Mark Vints, Gennadij Andreev, Jaroslav Gerbos, Peter Zimnikoval, Mirko Nitschke, Ralf Koschack, Kathrin Düber (hidden), Casper ter Kuile, ?? and Cis Verbeeck (credit Marc de Lignie).

Jürgen Rendtel guiding through the observatory parc, from l. to r. Daniel Ocenas, Ulrich Sperberg (in front),Jürgen Rendtel (partly hidden), Malcolm Currie, Mark Vints, Gennadij Andreev, Jaroslav Gerbos, Peter Zimnikoval, Mirko Nitschke, ??, Kathrin Düber, Casper ter Kuile, ??, Cis Verbeeck, Oleg Bel'kovich, Ragnar Bödefeld, someone hidden, Pierre Bader, Peter Aneca (hidden), Roland Winkler, Marc de Lignie, someone hidden and André Knöfel (credit Paul Roggemans). Jürgen Rendtel guiding through the observatory parc, from l. to r. Daniel Ocenas, Ulrich Sperberg (in front),Jürgen Rendtel (partly hidden), Malcolm Currie, Mark Vints, Gennadij Andreev, Jaroslav Gerbos, Peter Zimnikoval, Mirko Nitschke, ??, Kathrin Düber, Casper ter Kuile, ??, Cis Verbeeck, Oleg Bel'kovich, Ragnar Bödefeld, someone hidden, Pierre Bader, Peter Aneca (hidden), Roland Winkler, Marc de Lignie, someone hidden and André Knöfel (credit Paul Roggemans).

The domes of the observatory, with Daniel Ocenas, Jürgen Rendtel (back), Malcolm Currie, Mark Vints, Gennadij Andreev and Peter Zimnikoval (credit Axel Haas). The domes of the observatory, with Daniel Ocenas, Jürgen Rendtel (back), Malcolm Currie, Mark Vints, Gennadij Andreev and Peter Zimnikoval (credit Axel Haas).

From l.to r. Ulrich Sperberg, Daniel Ocenas, Jürgen Rendtel guiding through the observatory parc, Malcolm Currie, Stefan Ströbele (in front), Mark Vints (partly hidden), Jaroslav Gerbos, Gennadij Andreev, Peter Zimnikoval, Ragnar Bödefeld, Mirko Nitschke and Casper ter Kuile (on the edge) (credit Paul Roggemans). From l.to r. Ulrich Sperberg, Daniel Ocenas, Jürgen Rendtel guiding through the observatory parc, Malcolm Currie, Stefan Ströbele (in front), Mark Vints (partly hidden), Jaroslav Gerbos, Gennadij Andreev, Peter Zimnikoval, Ragnar Bödefeld, Mirko Nitschke and Casper ter Kuile (on the edge) (credit Paul Roggemans).

A Zeplin passed over the observatory (credit Axel Haas). A Zeplin passed over the observatory (credit Axel Haas).

Daniel Ocenas and Peter Zimnikoval (credit Marc de Lignie). Daniel Ocenas and Peter Zimnikoval (credit Marc de Lignie).

Daniel Ocenas, Mark Vints and Malcolm Currie observing the Zeplin (credit Paul Roggemans). Daniel Ocenas, Mark Vints and Malcolm Currie observing the Zeplin (credit Paul Roggemans).

Historic building in Potsdam (credit Axel Haas). Historic building in Potsdam (credit Axel Haas).

Leaving Potsdam by ship with in the back the dome of the St Nikolai church (credit Axel Haas). Leaving Potsdam by ship with in the back the dome of the St Nikolai church (credit Axel Haas).

Enjoying the light of the sun over the water (credit Paul Roggemans). Enjoying the light of the sun over the water (credit Paul Roggemans).

From l.to r. Gennadij Andreev, Oleg Bel'kovich, Marc Gyssens (back), Paul Roggemans, Alexandra Terentjeva and Roland Winkler (back) (credit Casper ter Kuile). From l.to r. Gennadij Andreev, Oleg Bel'kovich, Marc Gyssens (back), Paul Roggemans, Alexandra Terentjeva and Roland Winkler (back) (credit Casper ter Kuile).

Arriving back at the IMC host (credit Casper ter Kuile). Arriving back at the IMC host (credit Casper ter Kuile).

The building of the hotel seen from the boat (credit Casper ter Kuile). The building of the hotel seen from the boat (credit Casper ter Kuile).

The building of the hotel seen from the boat (credit Casper ter Kuile). The building of the hotel seen from the boat (credit Casper ter Kuile).

At the evening the barbecue from l.to r. Marc de Lignie, Mark Vints, Casper ter Kuile (back), Cis Verbeeck and ?? (Back) (credit Axel Haas). At the evening the barbecue from l.to r. Marc de Lignie, Mark Vints, Casper ter Kuile (back), Cis Verbeeck and ?? (Back) (credit Axel Haas).

Irmgard Schmidt at the Saturday evening barbecue (credit Axel Haas). Irmgard Schmidt at the Saturday evening barbecue (credit Axel Haas).

Roland Egger at the Saturday evening barbecue (credit Axel Haas). Roland Egger at the Saturday evening barbecue (credit Axel Haas).

At the Saturday evening barbecue, from l.to r. ??, Roland Winkler, Ulrich Sperberg, Pierre Bader, Marc Gyssens, Jürgen Rendtel and Paul Roggemans (credit Axel Haas). At the Saturday evening barbecue, from l.to r. ??, Roland Winkler, Ulrich Sperberg, Pierre Bader, Marc Gyssens, Jürgen Rendtel and Paul Roggemans (credit Axel Haas).

Malcolm Currie presenting 'The Taieri Plains Fireball of 1985 May 06 in New Zealand' for Graham Wolf (credit Casper ter Kuile). Malcolm Currie presenting 'The Taieri Plains Fireball of 1985 May 06 in New Zealand' for Graham Wolf (credit Casper ter Kuile).

'The Taieri Plains Fireball of 1985 May 06 in New Zealand' prepared by Graham Wolf (credit Casper ter Kuile). 'The Taieri Plains Fireball of 1985 May 06 in New Zealand' prepared by Graham Wolf (credit Casper ter Kuile).

Alexandra Terentjeva at the overhead, Malcolm Currie (in front), Paul Roggemans, Jürgen Rendtel, André Knöfel (back), Rainer Arlt (hidden), Petr Pravec (front) and Ina Rendtel (credit Axel Haas). Alexandra Terentjeva at the overhead, Malcolm Currie (in front), Paul Roggemans, Jürgen Rendtel, André Knöfel (back), Rainer Arlt (hidden), Petr Pravec (front) and Ina Rendtel (credit Axel Haas).

Alexandra Terentjeva presenting 'Some Meteor Puzzles' and session chairman Paul Roggemans, seated in front André Knöfel, Jürgen Rendtel and Ina Rendtel (credit Casper ter Kuile). Alexandra Terentjeva presenting 'Some Meteor Puzzles' and session chairman Paul Roggemans, seated in front André Knöfel, Jürgen Rendtel and Ina Rendtel (credit Casper ter Kuile).