Sunday, February 9
It had been cloudy and snowy due to strong cold wave, but finally, we had a stable clear sky. This was the first comet hunting session in February. It was clear sky and windless with the air temperature of -10C. The record low throughout my comet hunting history circa three decades! Having said so, I felt chillier when temperature is plus a few degrees with strong wind.
Shogo Utsunomiya, a comet hunter living in Mimami-oguni, Kumamoto, told me that an air temperature reaches -15C at his observatory. He said he bought a down jacket but he had never worn it, because the walls of his observatory protect him from winds and kept warm.
NGC6633, an open cluster in the constellation of Ophiuchus. The image is 60f wide.
The Digitized Sky Survey copyright © 1994
I often searched along the ecliptic mainly Scorpius and the western part of Sagittarius last month. There are many open clusters and spent a lot of time to identify. This time, I began with M14, a globular cluster in Ophiuchus, more northernly the region, using a glass eyepiece (Ethos 21 mm, 97x). Although there are less globular clusters in the area, many stars shine in the FOV as it overlaps with the summer Milky Way. Numerous open clusters are sparkling like a blooming flower. The most impressive open cluster I observed this time was NGC6633.
Generally, the colder the amount of water vapor in the atmosphere decreases making transparency high, the better the star visibility is. Today, stars shined beautifully, and the observing site was covered with pure white snow as Minoru Hondafs poem.
May the starlight be purely transparent
The flowers beautiful in spring
Water flow crystal clear in summer
Breezing refreshing in autumn
and
Pure white snow fall in winter
I take a decent measure to protect against cold during the comet hunting session, and I do not feel chilly up to the air temperature of -5C. However, under the temperature lower than that I feel my fingertips cold. On the other hand, it is inefficient to use gloves with heater, because it requires more time and effort for preparation.
The time when I completed the session, Scorpius shines splendidly on the east. The season when Scorpius rises in the eastern sky at predawn, the coldness reaches its peak as Tsutomu Seki wrote in his publication.
Sunday, January 12
I went on a comet hunting everyday Wednesday Jan. 1 through Monday Jan. 6 thanks to good weather at the beginning of the month. Among those days, the forecast predicted clear sky on Thursday, and I drove to the observing site. However, it was cloudy at the site and there was no expectation to recover, and I returned back to my home. On Sunday, soon after I started comet hunting clouds began to cover the sky, and I searched only 20 min in total.
Observation site with slight snow cover. The photo was taken after the session on Saturday, Jan. 11.
Yesterday, Saturday Jan. 11, it was cloudy around my house, however, the Super Computer Weather predicted recovery of the weather. Unexpectedly, soon after I left home for the site, snow started to flicker. I did not care and drove around 10 min, but snow began to fall in earnest. I parked my car to confirm the radar image using my smart phone, but no snow clouds. I headed to the site believing the forecast. At 3:45am local time, I arrived at the site and it was snowing but I could see some stars through thin clouds. There was slight snow accumulation there. I decided to wait for the recovery of the weather.
At 4:15am, it stopped snowing and starry sky began to open up. I set up my telescope and was ready to observe at 5:00am. In summer I am ready to observe within 30 min after arrival, but in winter it takes 45 to 50 min: wearing polar jackets, pants and boots, preparing disposal chemical heater for my back and toes, slow motion due to low temperature. The thermometer indicated the air temperature of -8C. It was windless but the coldest predawn chill this winter.
When I lived in Niigata Prefecture, I observed at the site with the altitude of over 900 m above sea level in summer, while 430 m above sea level in winter because the roads are closed due to snow. The record low of the air temperature at that time was -8C. The coldest record during comet hunting session after moving to Kumamoto was -9C at the present observation site with the altitude of 850 m.
On Saturday before the comet hunting session, I observed Omega Centauri that rose 4 above the horizon with Ethos 21 mm, 97x. Although it was slightly dark because it was still low altitude (9 at the meridian), the cluster contains a great number of stars and impressive enough as the most beautiful globular cluster in the entire sky.
I started sweeping the sky from Ώ Librae, Zubenelgenubi at 5:04am. The deep sky objects I encountered were NGC5796, 5897, a pair of galaxies 5915 and 5916, M4, M30, M62 and M19. When I spotted NGC5915 (magnitude of 12.3), I identified it referring to SkySsafari 7 Pro, a digital map. On the map, a darker galaxy, NGC5916 (magnitude of 13.2), was shown in the south of NGC5915 and I noticed in the FOV.
NGC5915 (center) and 5916 (lower center). The image is 30f in width
The Digitized Sky Survey copyright © 1994
Double stars looked beautiful since a glass eyepiece was used for the session instead of Night Vision that produces black and white images. The most impressive one during the session was ΐ Scorpii. The primary star was golden and the secondary light blue. The scintillation deformed them and it looked like they were smiling and dancing.
I stayed at the site after the comet hunting session that ended at 6:21am, 30 min after the start of the twilight, to observe C/2024 G3 ATLAS. The comet rose at 6:29am, but there were clouds at the low altitude and I could not observe the comet. The clouds moved slowly, and I continued observation. At 6:41am, I found the comet with a tail 0.1 long using 7x50 mm binocular. The altitude of the object was 1.2. I could not see it with naked eyes. The comet was visible for a while disappearing in and out of the clouds. I could not aim the 46 cm telescope at the comet because grasses at the site hided the comet. While I was taking down my telescope, the sun rose at the direction where the comet rose. I visited
the site hundreds of times, but this was the first time I saw sunrise here. It was so refreshing to watch the sunrise after observing the bright comet.