2003 diary

From my recent diary in 2003

Mon Dec 15

Winter has come. We have to patient here in Japan Sea Side because bad weather lasts for a few months in winter.　In Pacific Side of Japan Islands there are a lot of clear days December to February, however. I expect to comet hunt a couple of times in January and February, respectively, at most.

This is the reason why I could not comet hunt since Nov 24. Gibbous moon was bright but I was satisfied with the pre-dawn seeking session after a long time absence.

Mon Nov 24

Five days ago I have moved to the apartment located on the outskirts of the city. There is only rice farm in the east of it and eastern sky is open. I tried to comet seeking in front of my apartment at this pre-dawn.

The sky was not dark as expected and haze gathered around the observing site because the apartment is in the shallow valley. The last 20 minutes of the seeking session, I felt the contrast in the telescope field was bad. When I was disassembling the telescope after the seeking session I noticed frost had been formed on the secondary mirror! Ouch! Weak fog was formed around the site and the secondary mirror was frosted over before you knew it.

This was the fifth comet hunting session of this month. Usually we have a lot of cloudy and rainy days due to winter type pressure pattern in November. However, there are many fine days in this year. This good weather compensated for bad weather of this summer.

I got tired this month because of good weather in addition to moving.

Wed Nov 5

Excellent transparency! I started from M65 in Leo at 3:08am and caught 57 nebulae (galaxies and globular clusters) for two hours. My record high was 61 nebulae in one comet-hunting session in this region: Leo, Vir, and Com. I could not identify so many galaxies without digital setting circles.

This was the second seeking session in this month.

Fri Oct 31

We have a lot of fine days and this is the eleventh comet seeking session in this month totaled both at dusk and pre-dawn. There is not a speck of cloud in the sky.　I conducted a vertical seeking from Hya to the back of Leo at pre-dawn and caught 21 nebulae and a star cluster, M67.

It was a very comfortable session and I enjoyed beauty of stars to my heart’s content.

I observed C/2001 HT50 LINEAR-NEAT before starting comet-hunting. I observed 157P Tritton for the first time. I could not afford to estimate brightness by comparing with stars because I wanted to spend time to comet-hunting.

Impressions
C/2001 HT50 (LINEAR-NEAT)
Looked like the same with the observation on Oct 27 (45.7cm 68x).

157P Tritton
I observed this comet for the first time. It could not be seen with 45.7cm 68x, but 170x and was about 13th magnitude with the size of 0.5’x1’ by intuition. It was very faint near the alpha Leo, Regulus.

Thru Oct 27- Fir Oct 28

After one hour and half of dusk seeking session on Thursday I estimated comet brightness as shown below. On Friday one hour after I started the session the sky clouded over.

2P/Encke
mag.=9.4, Dia=4', DC= 1...45.7cm L (68x)
This estimation might be too bright? Very diffused and large. It must be difficult to catch it during searching session at low altitude.

C/2001 HT50 (LINEAR-NEAT)
mag.=11.5, Dia= 1.7', DC=6, Tail: 3.4' in PA 75 deg...45.7cm L (68x)
The tail was apparent at 68x and more evident at 170x.

C/2002 T7 (LINEAR)
mag.=10.7, Dia=0.7', DC=7...45.7cm L (68x)
The comet looked like a planetary nebula with rather clear outline.

Fir Oct 17-Sat Oct 18

Clear sky since Oct 1! I drove to the high altitude observing site, 1100 m where it took one hour from my residence. After assembling the telescope, wind became strong and I could not see the telescope field. Ouch! I decided to move to lower altitude. On my way to the second observing site I saw a few big animals on the road. Bears! A parent with two young. They were astonished with the headlamp and went away.

I assembled my 18” reflector again at the observing site. I felt the seriousness of the light pollution at lower altitude and comfort of windless site. The last quarter moon rose when I completed one hour comet hunting session. It looked calm and fantastic.

I slept well in my car for 5 hours and woke up at 3am. I swept the north-eastern sky for one hour and half under the moonlight.

Thurs Oct 16

I went comet hunting in the pre-dawn of Oct 7 but was clouded out 15 minutes after I started. Since then there was no fine day except last week: it was full moon.

I attended annual meeting of the Japanese Society of Snow and Ice last week. I enjoyed talking with Osamu Abe, a discoverer of Comet Abe 1970g, not about snow sciences but about comet hunting. Incidentally, both he and I are snow scientists and the members of the society. Is this something to do with “dirty snow ball”? He said he sometimes seeked a comet using 12 cm binocular.

Weds Oct 1

Pre-dawn sky was very clear, today!
Because of the winter type pressure pattern it had been oppressive weather since Sep 23 here in Niigata-ken, though western Japan including Tokyo area had been clear.

I began to comet hunting at 2:55am from the foot of Gemini and finished at 4:44am at the foreleg of Leo. Colors of some double stars that I came across were crystal clear and I felt as if I had been absorbed by them.

When I looked up the sky just at the beginning of the twilight, Milky Way drew a large arc across the whole sky and it met zodiacal light at Gemini released from Leo. Milky Way is tens of thousands light years away, while zodiacal light is in our solar system. How impressive it is to see 3-dimentional view of our universe!

NGC2903 was caught at 4:40am, about 30 minutes after the beginning of the twilight.

Mon Sep 22-Thur Sep 23

I enjoyed superb sky through the night!

A typhoon went through the south coast of Japan and the outlook said that it would be clear sky in the evening on Monday. Actually, it was cloudy in the evening but extremely transparent sky excited me in the midnight. Comet Ikeya-Seki was discovered in September just after passing a typhoon by Seki and in the typhoon by Ikeya; Ikeya found it when the center of the typhoon was passing over his town! The sky is clear in the center of a typhoon, what we call 'The eye'.

I arrived at an observing site before the end of twilight and comet hunted for about four hours in total, on top of deep sky objects watching for some two hours. Fortunately, it is national holiday today and I took enough rest in daytime.

Impressive objects were as follows.

Veil nebula in Cyg could be seen by 8x35 mm binocular, and is always impressive with 18” combined with OIII filter.

I observed outer halo of M57 using OIII filter at 170x. Some outer halos of planetary nebulae are visible with a large aperture with the filter (Sky & Telescope, October issue, 2003, p.111-113).

Super nova in NGC1201 was easy with 18” 68x, the magnitude was about 13th.

Fri Sep 5

The sky became clear since Aug 23 and the transparency was perfect! I was exited and started comet hunting at mid night.

I caught more than two dozens of faint nebulae which were the magnitudes of 12-13th. The most impressive one was UGC1214 that was not included in the computer of the digital setting circles. I confirmed it by the Uranometria. It looked like a star at a glance, but was not perfect spot image. The excellent optics made it recognizable. As Tsutomu Seki mentioned an excellent optics has the highest priority as a comet seeker.

I pointed my telescope at M45 to enjoy excellent sky and saw the reflection nebula around Merope extended over 0.6 degree in length.

Sat Aug 23

A search of this predawn was rather satisfactory. 60% of the sky was always covered with cloud but its motion was slow and I was not often interrupted. Nevertheless, I changed the search area twice because of cloud. Transparency and seeing was good and I could catch a couple of faint nebula in spite of the moonlight: NGC1184 and 1788. The former, about 13th magnitude, was the limit of my telescope’s capacity under that condition.

During comet hunting I enjoyed Mars watching. Mars image of this dawn was the highest quality I have ever seen! It was a great view. The surface pattern was very complicated and subtle with a small polar cap.

The forecast of the next week is not desirable and this might be the last observing in this month.

Fri Aug 15

I went to comet hunting in the evening. I began to search 21 minutes before the end of twilight (19:53pm) and ended at 18 minutes after the moonrise when the cloud covered all the sky (20:52pm).
Most of the time the clouds covered more than 70% of the sky and I searched through the gaps of clouds here and there.

When I caught a comet like object I tried to identify it using Super Navigator (digital setting circle) but it showed no candidate! I was a bit excited; however, it proved to be NGC4449 when I tried again after setting the limiting magnitude of Super Navigator for fainter. Soon after that it disappeared in the cloud.

Such kind of excitement is a joy of the hunting.

I went to comet search at the predawn of Aug 8 too, but at that time I could comet hunted only 40 minutes due to clouds.

It is near the end of August now. However, the anticyclone in the Sea of Okhotsk is strong, which usually weakens in summer. It has been cool, cloudy, and unfavorable weather. The rainy season still lasts in my impression.

Mon Aug 4

I began to search from the south of M45. No comet like objects were caught today's session but a few open clusters.
I heard a big animal tread the brush near the observation site and was terrified. It must be a bear! The local newspapers reported bears appeared around this area many times. I cried against him then he went away.

After the session I drew rough drawing of Mars.

The weather forecast said it will not be fine this week.

　18"291x　Aug 4 2003 4:05 Local time. The right edge looked white and shining. It might be cloud.　

Sun Jul 27 - Mon Jul 28

The Meteorological Office said that it looked like the rainy season had finished on July 27 in my prefecture. But I doubt it. As far as I remember the final announcement on the finish of the rainy season is made after summer, however, temperature is still low at present and northern cold anticyclone gives this fine weather.

Anyway, I enjoyed comet hunting on July 27 since July 3. It was clear in the evening but just after the end of twilight it was cloudy except low SW-S sky: lower than 10 degrees from the horizon with the width of 50 degrees. It was the only sky area I could search. In spite of the low altitude star looked clear due to high transparency.

After the dusk searching session I slept in my car at 9:40pm, and woke up at 1:30am. It was very fine. Several shooting stars crossed my telescope field. The waning moon, age 29, was fantastic in the twilight.

Thurs Jul 3

This morning it was cloudy and thin cloud covered the area I sought for some time. I could search only one hour out of two hours. I caught M77 at low altitude but did not M74 probably due to coverage of thin cloud.
After comet hunting I observed Mars but it did not see well because of poor seeing.

Sun Jun 22 - Mon Jun 23

More than two weeks have passed since I went on comet hunting last because of bad weather in rainy season. Fortunately, it was fine last night and I could enjoy comet hunting at last dusk and at this dawn. I slept in the car for two hours between dusk and dawn searching sessions.
Mars is approaching our planet and is bright in the morning sky. I pointed my 18" telescope to it just after I completed my comet hunting at dawn. The large south polar cap was very impressive. Venus was seen at very low altitude on my way home.

Home