Introduction
For a long time, I had been looking forward to the 2017 return of the Geminids. In 2015, I was impressed by the activity and the many bright meteors of fireball class. Also in 2016, I witnessed many bright meteors under a moonlit sky during the maximum. This year, observing conditions would be near perfect, and the only thing that could ruin the show, was bad weather. The weather forecast was quite depressing, except for one night. On the evening of December 12, the sky was clear, and I was excited to check out the activity more than a day before the expected maximum.
Preparations
I chose an observing site on an icebound lake, some 20 minutes driving from home. This place is far from any sources of light, and the horizon is nearly perfect. The temperature was very cold, about -14 degrees Celsius, so I was prepared for a freezing night. Despite the cold, it was a fantastic natural experience to lay down on the sunbed and listen to the sounds of the forest. The cracking of the ice sounded like a symphony from all around the lake, and sometimes from right under my sunbed! This made my heart jump a couple of times, but I knew the ice was thick enough. Anyway, it helped me not to fall asleep! Also, the screams of a nearby fox contributed to my alertness, and I was more than ready for what the Geminids would bring of further excitement.
Observations
The observation started 20:45 UT, but i soon became aware of some unexpected clouds coming in from the west. These clouds lasted for about an hour, and affected the Geminid rates the first hour. I chose to count Geminids in 20 minutes periods, and in the three first periods rates were 3, 3 and 7. The next hour the clouds disappeared, and the LM also improved somewhat. The 20 minutes rates for this hour was 8, 9 and 12. The last hour before a short break, yielded 20 minutes rates of 14, before a sharp fall to 4 and 7. The meteors these first three hours were quite weak, with only one Geminid of -1 magnitude, and two of 0 magnitude.
After 3 hours of observation in -14 degrees, I had to take a break to get some food, and change battery on my camera. After this my fingers were so frozen that I had serious problems to handle my cassette recorder and the remote control on my camera. After some minutes warming my fingers against my body, they were functional again, and observations could continue. I started observations again 00:05, and the next hour gave 20 minutes rates of 10, 12 and 14. Activity culminated between 01:05 and 01:25 UT, when 16 Geminids were seen, followed by 9 and 12 in the next two periods. There were also a lack of very bright meteors during these two hours, but 5 Geminids reached magnitude 0. After 5 hours of observations, I had to drive home to get two hours of sleep before going to work. The next night was unfortunately clouded, but I was happy to at least have seen some of the activity of this years Geminids.
Observational data
20:45 – 21:05: Teff: 0,333. F: 1,17. Lm: 6,11.
ANT: 0, DLM: 0, MON: 0, NOO: 0, SPO: 0, GEM: 3(2, 5(2)
21:05 – 21:25: Teff: 0,333. F: 1,11. Lm: 6,11.
ANT: 1(5), DLM: 0, MON: 0, NOO: 0, SPO: 1(5), GEM: 3(0, 1, 2)
21:25 – 21:45: Teff: 0,333. F: 1,05. Lm: 6,23.
ANT: 0, DLM: 0, MON: 2(4, 5), NOO: 2(3(2), SPO: 3(1, 3, 4), GEM: 7(-1, 1, 3(2), 4(2), 5)
21:45 – 22:10: Teff: 0,383. F: 1,00. Lm: 6,23
ANT: 0, DLM: 1(5), MON: 0, NOO: 0, SPO: 1(5), GEM: 8(2, 3(4), 4, 5, 6
22:10 – 22:30: Teff: 0,333. F: 1,00. Lm: 6,30
ANT: 0, DLM: 0, MON: 0, NOO: 0, SPO: 1(4), GEM: 9(1(2), 2, 3, 4(3), 5(2)
22:30 – 22:50: Teff: 0,333. F: 1,00, Lm: 6,30
ANT: 0, DLM: 0, MON: 0, NOO: 1(3), SPO: 3(0, 2, 3), GEM: 12(1, 2(2), 3(3), 4(4), 5(2)
22:50 – 23:10: Teff: 0,333. F: 1,00. Lm: 6,30
ANT: 0, DLM: 0, MON: 0, NOO: 0, SPO: 2(1, 6), GEM: 14(0, 1(2), 3(4), 4(2), 5(3), 6(2)
23:10 – 23:30: Teff: 0,333. F: 1,00. Lm: 6,23
ANT: 1(3), DLM: 0, MON: 0, NOO: 0, SPO: 1(1), GEM: 4(2, 3, 5, 6)
23:30 – 23:50: Teff: 0,333. F: 1,00. Lm: 6,23.
ANT: 0, DLM: 0, MON: 2(2, 4), NOO: 0, SPO: 2(2, 4), GEM: 7(1(2), 2, 3, 4(3)
00:05 – 00:25: Teff: 0,333. F: 1,00. Lm: 6,30
ANT: 0, DLM: 0, MON: 0, NOO: 0, SPO: 1(4), GEM: 10(1, 2(3), 3(2), 4, 5(2), 6
00:25 – 00:45: Teff: 0,333. F: 1,00. Lm: 6,30
ANT: 0, DLM: 0, MON: 0, NOO: 0, SPO: 1(4), GEM: 12(0, 1(2), 2(4), 3(3), 4, 5
00:45 – 01:05: Teff: 0,333. F: 1,00. Lm: 6,30
ANT: 2(2, 3), DLM: 0, MON: 0, NOO: 0, SPO: 3(2(2), 3, GEM: 14(0, 1(2), 2(2), 3, 4(3), 5(4), 6
01:05 – 01:25: Teff: 0,333. F: 1,00. Lm: 6,30
ANT: 0, DLM: 0, MON: 1(3), NOO: 1(3), SPO: 0, GEM: 16: 0(3), 1(3), 2(2), 3(3), 4(4), 5
01:25 – 01:45: Teff: 0,333, F: 1,00. Lm: 6,30
ANT: 0, DLM: 0, MON: 0, NOO: 0, SPO: 3(3(3), GEM: 9(1(2), 2, 3(2), 4(3), 6
01:45 – 02:05: Teff: 0,333. F: 1,00. Lm: 6, 30
ANT: 1(5), DLM: 1(4), MON: 0, NOO: 0, SPO: 3(2(2), 5, GEM: 12:(1, 2(4), 3(4), 4(2), 5
Great report Kai! Must be a cold session 🙂
My coldest session was during the famous Leonid outburst of november 16/17, 1998 at the Delingha Radio Observatory in China.. Temperatures dropped to -17 degrees and we observed almost continueus for 6 hours. During the night 18/19 november I stayed at a small compound (as part of a droppost for photographic meteorwork), there temperatures were below the -20 degrees…. But I think you have must much colder sessions then I?
Hi Koen.
It was a cold session indeed, but the cold is really not a big problem if you are prepared for it. I use a hand warmer to heat up my camera lens during cold nights. These are small bags, with energy stored in some kind of salt, and heat is released when they come in contact with air. Guess i have to buy some for my hands and feets also,before the next cold observing session. You are right that i have experienced cold sessions before, but it is very rare that temperatures fall below -20 degrees.
One of my coldest experiences also came during an outburst of meteors, a cold December evening in 1986. This was in the very beginning of my “career” as meteor observer, and my observing equipment was not very suitable for cold observing nights. Temperatures that evening was -22 degrees, and i had a very thin layered sunbed, and an old, worn out, military sleeping bag from the 1960’s. My plan was to go outside to get an hour of observations of the Ursids, a meteor shower i had never seen before. After some minutes of observations, i realized that activity was much higher than what could be expected, and i had to continue observations for a much longer time than planned. After that night, i bought a modern sleeping bag, that could resist temperatures down to -40.
It must have been a fantastic experience to witness the 1998 outburst of the Leonids! Each observing session is unique, and to observe meteors from a foreign place when something unexpected happens, creates memories that are with you forever! As i remember, the 1998 outburst was full of bright meteors also? I observed the 1999 outburst of the Leonids from Tenerife. The abundance of meteors that night, at times gave me the feeling of being in motion through the universe. Not so many bright meteors as in 1998, but at least the temperatures was very relaxing!