Leonids 1999 Observing Campaigns
Organized by the Space Science Department (SSD) of ESA, a team of six observers will observe the Leonids from two locations in Southern Spain. Another observer will participate in the American Leonid Multi-aircraft Campaign (Leonid MAC) to observe the Leonids from an altitude of 10 km above Spain and Israel.
The following report is a diary from the ground-based group:
OSN - 10 November 1999
We are packing! Joe Zender, Detlef Koschny, and Andre Knöfel will take a van and drive from Holland to Spain with all our equipment. In total, we take 11 intensified video cameras, with VCRs, power supplies, tripods, several computers, a radio receiver station to detect reflections of the meteors, warm clothes, and much more...
All cameras were tested, one does not work properly yet but we decided to fix that on the mountain. We leave Noordwijk around 16:00 on the 10 November, heading south. To get to Grenada on time, we decided to drive through the first night. One person drives, one person keeps the driver awake, the last one sleeps. After a few short stops for refueling and grabbing some food, we arrive at a small hotel close to the highway, about one hour north of Grenada, on the evening of 11 November.
OSN - 11 November 1999
Unfortunately we have clouds, so we could not check whether the 'Linearids' were visible. This was the newly predicted meteor shower from the comet Linear, which might have been visible in the evening of 11 November. Hopefully, other groups had better weather.
In the morning, just as we get ready to go, a police car stops next to our car. "Who are you? What's in all those boxes?" they said - of course in Spanish. We didn't understand them, and they didn't understand English. Fortunately, mentioning the name of our contact person here at IAA, Jose Juan Lopez-Moreno, prompted one of them to say something like "professor of astronomy in Grenada", so obviously he knew him. He convinced his colleague to let us go...
We arrived at the Institute for Astrophysics in Grenada around noon time. The first message by Jose Juan (called Pepe) is: It snowed last night, and there is no way to go up to OSN! We called Calar Alto Observatory (CAHA), and the news there is: it is snowing right now, and there is no way to get up. Of course we are a little bit disappointed right now and considering what we can do. TV producers Isabelle Leonard and David Whitbourn,(commissioned by ESA Science) just joined us, so they are setting up to do some interviews for ESA TV. In a few hours, Joe will go to the airport and pick up our two colleagues from the Werkgroup Meteoren. And then, we'll probably stay in Grenada and wait...
CAHA - 12 November 1999
We finally decided to go all together up to Calar Alto. The situation at the observatory of the Sierra Nevada (OSN) still looks bad and we do not expect that we can get up there before Monday morning because of all the snow.
It's late and we prepare for the coming nights by catching some sleep NOW...
CAHA - 13 November 1999
The night from 12 to 13 November was cloudy and the CAHA night assistant proposed that we wait until daylight to set up. So we get up around 9 o'clock to beautiful blue skies and sunshine. But our out that our van doesn't work anymore! Maybe the Diesel doesn't like the -5°C? Anyway, we get an offer of help the observatory staff. We unload our van into "No. 7", a small Renault from CAHA. The last 100 metres we have to carry our boxes to the wooden hut which will be our observing site for the next few days.
The "computer room", unfortunately, has no heater, so the inside temperatures are the same as outside! But at least we are sheltered from the wind. And we are promised heaters for tomorrow. The mess slowly mutates to chaos. The chaos is interrupted by lunch break. After that, Marc and Mr Schulz from CAHA put the van in a large garage. There it is warm and they are also able to charge the battery.
The rest of the afternoon we are busy setting up our equipment:
While we set up, David and Isabel (the TV team) join us with their TV camera and film our activities and the nice view around us - snow-covered trees, telescope domes, and beautiful blue sky.
In the meantime, the chaos is no more. Several tables are covered with equipment, and most of it is working. As night falls, we see the first stars through our camera systems, orient them in the right direction and focus them. Unfortunately, the sky is not so nice anymore, and we do not start yet with systematic observations.
CAHA - 14 November 1999
Report from Calar Alto meteor team Jo Zender of ESA/SSD, Andre Knöfel, Joost Hartman and Marc Neijts. "Werkgroep Meteoren", a part of the Dutch NVWS (Nederlandse Vereniging voor Weer en Sterrenkunde).
Andre and Detlef went to bed quite early, because they left for Granada early in the morning. We had a wonderful, clear night and saw quite a number of meteors. The Leonids seem not to be active yet, and most of the meteors we saw were sporadics or Taurids.
We operated one camera during the second half (clear sky) of the night and did some flatfielding and testing of the CCD (2kx2k) photometrics camera. Unfortunately, we experienced a lot of problems with the power supplies. Computers rebooted several times during the night and observations had to be restarted. There seems to be a problem with the Earth leakage circuit breaker and no obvious solution to it was found. We disconnected the fuse and will see tonight what will happen. Marc is setting up his radio experiment and spends quite some time of the time with searching for the right radio frequencies.
Communication is difficult up here. There are only two places up here at the mountain, where the GSM phones work - if we stand in exactly the right spot! Nevertheless we try to stay in contact with the Detlef and Rainer at OSN, and Erica and Cees, the Science web team at ESTEC and the ESOC people in Darmstadt.
Joost, Marc and Joe
CAHA - 18 November 1999
First impression from Calar Alto 03:45 UT
We had a fine display! We estimated between 600 and 1000 meteors an hour, not storm level but very impressive. At this moment the rate is still 3-5 per minute. It was a cold -6°C, clear night with a moderate wind, which keeps your feet cold enough.
Greetings from 2200 metres! The team from Calar Alto, Spain:
OSN - 18 November 1999
Report from Sierra Nevada - We saw it!
The predictions were right! Between 02:03 and 02:04 (local time) Andre saw 110 meteors, and I saw 40. Corrected for our different eyesights, this corresponds to a Zenithal Hourly Rate (zhr) of over 10 000! In total, each of us saw more than 1 000 meteors in about 3 hours of observing time.
We did not see any fireballs, i.e. no meteors brighter than the stars. A preliminary check of our video tapes showed that the highest meteor activity took place in the brightness range of the naked eye.
While the sky was clear, the wind was horrible - we had wind speeds between 40 and 70 km/h, storm gusts! The snow was blown in our face and made standing outside a challenge. With chill factor, we had temperatures of -28°C. Special thanks to Udo Telljohann, who loaned me some of his low-temperature clothing intended for a trip to Kiruna - I did not notice the temperature at all!
No long-lasting persistent trails were visible, so even though we were prepared to point our 1.5-m-telescope to do spectroscopy, we did not get the chance to do it. However, the other video cameras operated well. Only our high-resolution imaging system was blown away by the wind 15 minutes before the peak...
As a first estimate, we have about 20 hours observing time in parallel with our Calar Alto station, so we will be able to determine many orbits and magnitude profile. We will also be able to determine flux rates from all wide-angle camera systems.
Rita Schulz and Luisa Lara (ESA/SSD) went down the mountain today with a motor sled. We will record the sky for another night and pack tomorrow morning.
Detlef and Andre
OSN - 19 November 1999
We prepared our visual observing reports which were immediately published by the International Meteor Organisation in their Leonid press release. Instead of sleeping, we packed in the morning.
Down where our van was waiting we unloaded from the Ratrac into our car and went to Grenada, picking up some souvenirs like 40 kg of the excellent Spanish "Jamon" and 50 litres of olive oil.
Andre and myself then drove to CAHA, where we would pack up Joe's equipment and spend the night.
CAHA - 22 November 1999
After a verrrrry long trip through Spain and France, we finally made it back... Here is our adventure story.
I was woken on Saturday morning at CAHA by André (Knöfel) with the words "Detlef - we have a problem". When I opened my eyes and looked outside, there was about 20 cm of snow. We got up anyway and had breakfast. The observatory (SNO) staff said that at some point a snowplough would clear the route down the mountain, so we should have no problem leaving the observatory. However, when we went to start the van, it refused! It seems our van does not like CAHA. We pushed the van out of the parking lot, almost freezing our hands off. We wanted to roll it down the hill, hoping to start it that way.
At the bottom of the mountain it was raining and raining. We decided to take the route back at the coast, since going via Madrid through central Spain would have got us into snow again. Arriving in France, close to Montpellier, around 22:00 in the evening, we were told at the gas station that the road between Nimes and Orange was totally blocked due to snow. So we made a detour, first in the direction of Marseilles and then north towards Orange. It soon started snowing heavily. And in Orange - the road further north was blocked! So it wasn't the road between Nimes and Orange, that was blocked after all, but after Orange! We had a long discussion what to do and after driving around in Orange for a while (passing the famous arena!) we decided to go back to Montpellier and head north from there. We drove through heavy snowfall in darkness for hours (and had some discussions about the similarity of snowfall as seen from a moving car and meteor stream radiants). At 5:00 in the morning we were back in Montpellier...
The road north was sometimes normal road and sometimes motorway. Going through the Massive Central we got some beautiful vistas of snow-capped mountains, seen from a snow-covered street... But at least there were no trucks on this route and it was not blocked.
The rest of the trip was quiet - we passed Paris on Sunday afternoon and reached Den Haag around 19:00. Oh no - the road was blocked again! Apparently, on the motorway between Den Haag and Leiden there had been a heavy traffic accident, so we spent about half an hour waiting until the police let us pass. But then we luckily arrived around 20:00 in the evening.
André spent the night at my place and went back to Germany early Monday morning. Joe and myself unloaded the van in the morning and brought it back to the rental agency. Now we are checking our data.
So what did we get out of all this? Well, a lot of adventure and a few very exhausted people. But also about 240 hours of video recordings of the night sky, some of that with stereo observations. So we will be able to do what we were planning to do - to determine number fluxes of the meteors with video systems, to determine orbits of Leonids and other meteors, and to look at the dependency of the observed meteor numbers to the radiant elevation (by comparing it to data from other groups with whom we collaborate).
Unfortunately, we did not have a long-lasting persistent meteor trail in the maximum night, so we did not get a spectrum of it. Also, the automatic communication to ESOC in Darmstadt failed and we had to give reports via email and telephone. These minor issues aside, the campaign was a very great success and a very interesting personal experience. And the next few months we will be busy looking at the data...