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2013

Tue, Nov 12

It may be my last update about my visual comet hunting. The light pollution has been increasing day by day, and I felt it would be meaningless to continue the search until I can move to a dark site.

Last month saw three predawn sessions. On Oct 02 I started sweeping from north to Jupiter at around 3:50 a.m. At 4:02 a.m. I was encountered with M44, which was followed by dazzling Mars some 4-min later. The crescent old moon crept above the hill in the east at 4:31 a.m. At 5:20 a.m. or thereabouts I knew I was passing by the region where spiral galaxy NGC 3193 lies, and therefore I tried my great efforts to peer through the eyepiece, in the hope of catching some hint of the object. However, I could see noting whatsoever. I ended this session at 5:37 a.m.

The second session was made on Oct 03. I thought it would remain cloudy yet as I glimpsed outside the window, it was clear! So immediately I started sweeping from Pollux at 4:40 a.m. I picked up no DSO during this session, which was ended at 5:35 a.m. The transparency at low elevations was poor.

The third session was on Oct 06 predawn, whose condition was the best. I could even discern the Milky Way in Monoceros vaguely. It was a bit windy, and dry. I started sweeping from Castor at 4:17 a.m. 3-min later I caught sight of a mag 5 whitish meteor flashing across in the FOV northwards. At 5:03 a.m. I glimpsed another meteor, of around mag 7, flashing westwards, in the FOV, when sweeping Leo Minor. Despite the great transparency, I still failed to pick up any DSO during the session, disappointedly. At 5:33 a.m. I concluded the session.

I managed to photograph comet C/2012 S1 (ISON) in the sessions on Oct 03 and Oct 06. Unfortunately the comet was still beyond my capability even under the best local weather condition.

I visually observed C/2013 R1 (Lovejoy) and C/2012 S1 (ISON) on Nov 07 predawn. The former was an easy object, bright and large (image). The latter, on the contrary, was much more difficult due to light pollution, yet I still managed to see it. It should have been a fairly easy binocular object at dark sites.

Fri, Sept 20

I had been waiting for the clear sky, and finally I was able to conduct three times of predawn comet hunting sessions respectively on Sept 14, 17 and 18.

Only past 5 a.m. could I begin the session on 14 due to the clouds, which dispersed from NE towards S and therefore revealed stars against the transparent sky. I could even discern the Milky Way overhead in such a plcae with so severe light pullution. I swept from the region close to the border between Gemini and Cancer and ended at 5:28 a.m., when Canopus succeeded to get rid of the clouds and began glimmering against the sky in dawning twilight. I did not pick up any DSO.

The condition on 17 predawn was much inferior as a comparison. The humidity was very high, and as a result, the visibility at low elevations was excessively poor. Before the session, I decided to attempt to photograph comet C/2012 S1 (ISON) through my camera + 200mm lens. It took me longer than expected to settle down everything so that the huting session was unfortunately delayed, which ony commenced at 4:21 a.m. I swept from the region around Jupiter. Beehive Cluster M44 entered the FOV at 4:42 a.m., followed by dazzling Mars 2-min later. The session was put to an end at 5:27 a.m. In spite of the poor condition, my setup still managed to record the comet successfully as expected.

The session on Sept 18 was started when the moon was to set. Before the session I was watching the Champions League match between Napoli and Dortmund. The visibility at low altitudes recovered somewhat, and I felt that the humidity dropped as well. I started sweeping from Gemini at 4:41 a.m. Yet no DSO has been picked up during the session. I ended the session at 5:29 a.m.

Lately a new comet C/2013 R1 of around mag 14 was discovered by Terry Lovejoy from Australia in Monoceros. The comet was placed not low in the predawn sky, however, surprisingly, the comet managed to elude many digital surveys. The comet was definitely not the target detectable with my comet-seeker. The light pollution is becoming more and more serious, wherefore I feel it greatly difficult to sustain my visual comet hunt here.

Yesterday I was informed by some of my friends that, astonishingly, my corona composite taken during the total solar eclipse last Nov was chose as the winner in the group Our Solar System of Astronomy Photographer of the Year 2013. I had never thought about winning any prize related to photography, since in my concept the astronomical photographs I take should convey scientific meaning which later can be used as data for further studies or research, unless the poor quality avoids doing so. During that solar eclipse, I planned to record any potential Kreutz group sungrazers heading towards the perihelion. However, unluckily none but one was near the sun thence, yet beyond the FOV of my image. On the other hand, I did plan to write out scripts, which are applicable specifically for imaging processing of the solar corona taken during total solar eclipses, as what Miloslav Druckmüller had done, but I never have the available time.

Sun, Aug 18

The weather has been very nasty since two consecutive predawn comet hunting sessions respectively on Aug 12 and Aug 13.

Transparency was great in the first predawn, and I could directly discern M31 by naked eye without myopic glasses on. The sweep started from somewhere near the border between Aries and Triangulum at around 3:23 a.m. I saw NGC 1893 in the FOV at 3:40 a.m., also noticing more and more clouds. A whitish Perseid meteor of mag 2 caught my notice at 4:09 a.m., which flashed in eastern Taurus. Fortunately it did not take me long to await the dispersion of clouds. At 4:22 a.m. NGC 1907 and M38 entered into the FOV, and 2-min later, there came M36. I happened to notice a 3 mag sporadic meteor in Perseus flashing towards southeast at 4:31 a.m. 8-min later, a bright Perseid of mag -2 trailing a faint train behind flashed across around the zenith. NGC 1778 entered the FOV at 4:47 a.m., followed by M38 3-min later again. At 4:56 a.m. I noticed another Perseid meteor in northern Auriga, of around mag 3. The session ended at 5:15 a.m.

I hesitated to conduct comet hunt on Aug 13 because of clouds. Initially the weather was superb before 2 a.m., and I noticed several bright Perseid fireballs at around 11 p.m. to 1 a.m. by casual observation, whenceforth the frequency of occurrence of bright Perseid meteors apparently decreased, and thin clouds increased considerably as well. I had though that if the weather remained thus poor, I would give up conducting comet hunt but to formally observe the Perseids. However, the weather recovered so I began my hunt at 4:10 a.m. and swept from southern Perseus. I saw a mag 0 Perseid meteor at 4:11 a.m. in eastern Andromeda, flashing westwards. 6-min later I saw another one but fainter, around mag 1.5 near the borderline between Andromeda and Triangulum, flying SW. 4:20 a.m. witnessed a bright member, of mag -2, from Orion to Eridanus, southwards. Apparently there were far more meteors I saw this predawn than the DSOs, as I only picked up NGC 2281 at 4:47 a.m. At 5:06 a.m. I serendipitously caught sight of yet another bright Perseid meteor, of mag -3, around the boundary between Andromeda and Triangulum, flashing towards southwest. I completed the session at 5:15 a.m., when I noticed a bright satellite which steadily moved in NE Eridanus, narrowly missed Rigel, and disappeared towards Sirius; it was identified to be HST.

Concurrently when I was sweeping the skies, my camera diligently kept imaging the region around M45, in the hope of catching any Perseid meteor that would be in rendezvous with the bright cluster. Fortunate enough, I did manage to catch a fireball. See here.

Sat, Aug 10

I managed to conduct comet hunt this predawn. The weather turned much better; despite some high thin clouds, at least the cloud coverge greatly reduced. The transparency was good, yet in low altitudes there was some haze. I started my sweep from eastern Aries at 3:30 a.m. I noticed that a star adjacent to the boundary between Taurus and Perseus appeared fluffy and there was apparently some nebulosity around at 4:28 a.m. I checked my star chart and identified it as a beautiful planetary nebula NGC 1514. At 4:55 I encountered with open cluster NGC 1893, followed by M36 only 2-min later which passed by near the edge. At 4:59 a.m. a bright meteor, of mag 6 or so, flashed across the FOV towards east approximately with hints of train, when I was sweeping the skies. It was the only meteor that I sighted in this hunting session. M37 entered into the FOV at around 5:02 a.m., gleaming against the brightening pale blue sky background mysteriously. The session came to an end at 5:14 a.m. When I was about to move things back indoors, excitingly, I noticed Sirius glittering above the hill!

Tue, Aug 06

I had been preoccupied with my paper in June and July so updating the diary is seriously laggard. In June after the last update, I conducted only two predawn hunting sessions on Jun 13 and 18 respectively. I could only sweep around clear patches between clouds for 3-min before overcast on Jun 13. Nor was I pleased with the predawn session on Jun 18. I started sweeping from western Pegasus at around 3:34 a.m. The search had to be encountered with clouds merely 12-min later and anon more clouds rolled in, and thereby I was almost overcast. At around 4 a.m. I noticed some clear patches and conducted incessant sweeps amongst cloud gaps. Yet I had to conclude the session very soon for it started to drizzle! In a word, the weather this June was very nasty.

In July I swept predawn skies five times. The predawn in Jul 1 witnessed great transparency. I started sweeping from the region close to Alpheratz (α And) at 3:14 a.m. A meteor flashed across the FOV at 3:52 a.m., around 8 mag, towards NE. 10-min later I picked up NGC 752, a bright open cluster. My sweep had to be bothered and overcast by clouds again since 4:08 a.m., when I happened to catch sight of another meteor of 6 mag or so flashing across the FOV northwards. I managed to resume the sweep since 4:18 a.m. and saw NGC 752 again 9-min later. At around 4:48 a.m. the third meteor of around 7 mag interloped the FOV towards northeastwards. I was forced to conclude the sweep in Auriga at 4:50 a.m. owing to the fierce invasion of clouds.

On Jul 5 I conducted the second predawn hunting session in July. The sweep was commenced from regions in Aries at 4:12 a.m. when the sky turned clear. 5-min later M 45 passed across the FOV near the edge and it came across the FOV right in the middle around 4:24 a.m. The session was paused due to clouds at 4:50 a.m. In the session on Jul 8 I only picked up M 45 during the sweeps. I started sweeping from Hammal (α Ari) at 4:24 a.m. when it became cloudless. Before the conclusion at 5:02 a.m., I intermittently noticed sudden brightenings of the sky background, because of lightnings in distance.

Jul 18 saw another predawn hunting session. As it turned clear I began sweeping somewhere between Aries and Andromeda at 3:50 a.m. About 20-min later, I noticed a fuzzy object, however, before I pinpointing the location and identifying it from my star chart, clouds rolled in and eclipsed everything. At 4:34 a.m. a bright whitish fireball of around mag -1 flashed swiftly in Cetus southward and the surrounding clouds were seemingly lit. I waited patiently yet in vain, as the clouds were getting thicker and thicker and finally it turned fully overcast at 4:40 a.m. There was no more chance for me before twilight turned too bright, so I gave up.

Only on Jul 31 did I get another opportunity for comet hunt again. I did not make any effort to identify the fuzzy object seen in the session on Jul 18 as it had been almost 2 weeks past already. It might be a faint binary stars or a group of asterism. The sweeps were commenced from Triangulum at 3:10 a.m. yet interference from clouds was incessant and I felt very unsatisfactory. At 3:58 a.m. I serendipitously sighted a greenish fireball of -2 mag by naked eye in Triangulum, flashing southwestwards, probably a member of Perseids? Clouds gradually dispersed, so I could enjoy the sweeps pleasantly. At 4:09 a.m. I picked up NGC 1893 in Auriga. Concurrently a 5 mag meteor flashed across the same FOV towards S. Only 3-min later M 36 entered the FOV, fabulous with packed stars! Successively around 4:14 a.m. M 37 passed across the FOV, close to the edge, not as spectacular as M 36. 21-min later, I picked up M 38 along with NGC 1907 in the same FOV, followed by M 36 again across the FOV near the edge.  I witnessed another meteor by naked eye flashing southeastwards in Cetus to Eridanus, around 2 mag, at 4:43 a.m. or thereabouts. 7-min later I caught NGC 1778. Before I concluded the session at 5:05 a.m., M 38 entered across the FOV for the second time at 4:53 a.m. After completing the hunting session, I enjoyed observing Jupiter and Mars. Io and Ganymede were both located apparently extremely close to Jupiter. I could not see any features in the tiny Martian apparent disk at 119x owing to the poor seeing.

On Aug 1 predawn the transparency was almost superb in spite of some clouds; I could see M 31 by naked eye without wearing glasses. I started sweeping from regions around the border between Andromeda and Triangulum at 3:12 a.m. A meteor of around mag 5 intruded the FOV when I was sweeping in Andromeda, northwards, at 3:47 a.m. I noticed an open cluster NGC 1582 at 4:05 a.m., followed by NGC 1664 2-min later. I glimpsed another swift whitish meteor of around mag 1.5, in Cassiopeia, eastwards, at around 4:20 a.m. I switched to horizontal sweeps as as to cover the regions in the same azimuths but remained unswept at 4:55 a.m. Only 2-min later I saw a meteor of mag 6 in Gemini, flashing towards NE. The session ended at 5:05 a.m.

The weather persisted on Aug 2 predawn. Before starting the session, I saw that there were clouds in the northern skies. The sweep commenced from Sheratan (β Ari) at 3:15 a.m. I saw a mag ~2 meteor acutely flashing towards NE in southern Aries by naked eye at around 3:30 a.m. Hyades entered into the FOV at 3:44 a.m. The sky bakground was found lit as the I was sweeping regions quite adjacent to the waning crescent moon, which even entered the FOV at 4:15 a.m. I saw an open cluster NGC 2169 at 4:21 a.m. It was 8-min later that M 45 came into the FOV. The last DSO I picked up during this session was M 1, which passed across the FOV at around 4:57 a.m. Acceptedly it was not an easy detection as the twilight had already begun. I ended the sweeps at 5:05 a.m.

I was able to comet hunt on Aug 4 once again. The transparency was excellent. It was at 3:49 a.m. that I noticed that the eastern skies turned clear, and thereby I immediately began the search from Almaak (γ And) thence. I identified NGC 1245 in Perseus at 4 a.m., which had to be the only DSO that I could picked up in this session. Soon there came in clouds and it turned overcast. I could not sweep the skies until 4:38 a.m. when the clouds started to disperse. Simultaneously, I glimpsed a meteor of mag 1 flying nearly along the borderline between Perseus and Taurus eastwards. But the clear patches did not last for long, as masses of clouds rolled in once again. I intermittently swept the regions until the twilight became too bright at around 5:03 a.m. In the twilight I found that the scope was covered with a layer of dew droplets. How humid!

Transparency in the following predawn persisted. I decided to photograph comet C/2012 F6 (Lemmon) before going to bed. Concurrently I observed the comet through the comet-seeker. Thanks to the great conditions, I could easily see the comet at my first sight. My estimates go as on Aug 04.73 UT, m1 = 10.4, Dia. = 2'.7, DC = 3/. I got up, prepared for comet hunt and checked the imaging setup at 3:15 a.m. However, to my surprise, I found that the optical lens had been covered with a thick layer of dew droplets, which I have never encountered with before! Consequently, the image quality gradually deteoriated as the stars appeared softer and softer. I felt extremely disappointed, but could do nothing to make up what I might lose. Nevertheless, I started the hunting session at 3:32 a.m. from Aries. 15-min later I picked up NGC 1746, and only another 3-min later, I saw M 1, still not an easy spot since it was still situated low and there was some smog around low elevations. At 4:18 a.m. NGC 2129 was captured, merely above the eastern hill. M 35 entered into the FOV at 4:40 a.m. Jupiter happened to be located in my searching path and came into the FOV at 4:44 a.m. The session was concluded at 5:07 a.m. By naked eye I noticed two bright satellites, the first one was the famous HST, and the second one was also renowned, ISS. The former was spot at around 4:12 a.m. in southern Perseus, steadily moving eastwards, whose brightness was peaked in Perseus, around 0.5 mag. The latter was first noticed around Polaris at 4:52 a.m., flying across Camelopardalis, Auriga, Taurus and Orion, whose magnitude climaxed similar to that of Capella.

This predawn I performed another hunting session, however, transparency was no longer optimal. I started sweeping from Almaak (γ And) at 3:25 a.m. 3:51 a.m. saw open cluster M 34 entered the FOV, teemed with stars! Yet it was the only DSO which I noticed during this session. As sweeping across the Milky Way, I found that there were numerous stars and varieties of asterisms across the FOV. My sweeps had to be meticulous and therefore slow. I concluded the session at 5:09 a.m.

Sat, Jun 08

The rainy season has come, so it is very rare to see clear skies. I could not conduct any comet hunting session last month completely owing to the nasty weather. Luckily a subtropical high pressure weather pattern invaded South China on May 31, lasting for about two days, and therefore I had two clear predawn for comet hunt.

I observed comet C/2011 L4 (PANSTARRS) on May 31 evening through the 8" comet-seeker. Despite being a circumpolar object, it never rises high enough to get rid off smog plus some light pollution in low elevations. As a result the observation was not very easy. Disappointedly, I failed to see its neck-line, however, I managed to capture it with my camera. Prior to the commencement of session on Jun 01, I also observed another comet C/2012 F6 (Lemmon). It appears very bright through the eyepiece against the strong moonlit background. Yet both the plasma and dust tails eluded me. Only when it was already 3:55 a.m. did I start the hunting session by searching from NW Pegasus; I did not pay attention to what time it was so thought it were still 3:30 a.m.! 6 minutes later C/2012 F6 entered into the FOV. I noticed some clouds in the west, moving swiftly easterward, ominously. Sure enough, I had to pause hunting at 4:20 a.m. as the clouds eclipsed the eastern sky. Soon, I was fully overcast. I had to wait patiently for any chance that the clouds might disperse. There were some clear patches amongst clouds at around 4:50 a.m., however, I also noticed that the twilight had already begun in that the sky appeared bluish. That was the end.

The conditions on the next predawn were even much better. The humidity decreased in particular. The Milky Way looked obvious across the whole sky. Had there been no moon! Before starting the session I observed C/2012 F6 again. The roundish fuzzy ball looks somewhat larger, probably attributed to the waning moonlight. I started searching from the same azimuth as the previous uncompleted session at 3:27 a.m. I saw C/2012 F6 once again at 3:33 a.m. as I swept downward. I barely saw M33 at around 3:45 am, which appears very diffuse; the moonlight still posed serious influences on fuzzy objects. At 3:51 a.m. I serendipitously witnessed a meteor of mag ~3 across from Lac to N Cep, in slow motion. I finished the sweep at 5 a.m. Before carrying back the comet-seeker, I enjoyed observing the moon at 119x. The seeing was decent.

Mon, Apr 15

It turned sunny yesterday; I managed to conduct the second comet hunting session this predawn in Apr.

I started sweeping from central Cygnus at 3:54 a.m. Regions below alt. ~15° were contaminated by strong smog, so I did not try to sweep these areas. Several open clusters in Cygnus were encountered but I did not specifically memorize them. As the twilight was brightening, I paused the sweep at around 5:08 a.m. and attempted to visually observe comet C/2011 L4 (PanSTARRS), however, disappointingly, it was still hidden by the woods on a small hill in NE. Only a goldish blazing star above the woods was seen by the naked eye -- Caph or β Cas. I aimed my comet-seeker at the region around, trying to pick up the stars around Shedir (α Cas) where the comet was located. Unfortunately once again I had no luck, becasue of the thicket. I stopped my vain attemp at 5:28 a.m., by which everything I moved outdoors had been severely sopped. How humid!

Sun, Apr 07

I returned from my hometown yesterday evening after the Festival Qingming. A powerful cold front swept across South China, expelling away the clouds and rains which had been prevailing since Mar 11. Morever, the temperature in Canton drastically dropped to 10 Celsius only, which I have never experienced in April in my memory.

I got up at around 3:30 a.m. this predawn for comet hunt. Everything was done except that I could not find my star atlas! What a mess! Finally when I found it, it was toward 4 a.m. So much precious time was lost! I randomly decided to search from SW in Lyra and started the sweep at exactly 4 a.m. Only two minutes later M 57 entered into the FOV, quite prominent. At around 4:24 a.m. I successively noticed two elegant open clusters that passed by the FOV -- NGC 6871 and NGC 6883, in Cygnus. I checked the time, 4:28 a.m. now. 'Maybe comet C/2011 L4 (PanSTARRS) is already high enough for me to observe,' I thought. So I paused the session and went to set up equipment for photographing the comet. However, all of my attempt were proven vain. I was unable to match the stars displayed in the camera screen with the star atlas on spot. The twilight was brightening rapidly, and I thought that I did not have to continue my struggle in a meaningful way; it was impossible for me to go back to comet hunt either. Seeing the gentle waning crescent moon, I went to photograph it instead.

Having moved everything indoors, I was determined to check what mistake I had made. The star patterns captured in the camera were identified bit by bit, and eventually I realized that I had seriously underestimated the obsrtuction of the woods on a small hill! The regions I shot were at least around 10 degrees away from the place where the comet was located. Great disappointment overwhelmed me. Had I realized the mistake earlier, I could still have some time for comet hunt under such clear predawn skies. Now I learned that the opportunity left me again, as the weather is predicted to turn cloudy and rainy anon. At the present time, it already overcasts tightly.

It is worthwhile to note that I journeyed to Yunnan specifically for observing C/2011 L4, along with several friends, from Mar 11 to Mar 16. We only won two successful evenings. Below shows the result from the first evening. I must complain that the wind was extremely strong, whereby many of the images were blurred unfortunately. Images from the second evening have been processed yet due to my preoccupation.

Sun, Mar 10

Clear predawn! It is so rare that I can enjoy so many clear nights in March here. Yet this predawn the transparency drastically deteoriated.

I decided to search from new regions by starting sweeping from RY Her at 4:18 a.m. 40-min later Coathanger (Brocchi's Cluster) entered the FOV. I came across globular cluster M71 at 5:27 a.m., however, it was almost overlooked in that it passed by near the edge and, more importantly, it is loosely concentrated, plus the sky background was very bright owing to light pollution. These were the only two deep-sky-objects I picked up during this session, which concluded at 5:54 a.m. I felt very dissatisfied with the ambient. It is a great shame that it is becoming more and more difficult to find the pristine nightsky nowadays.

Sat, Mar 09

Another clear predawn! Also the most transparent predawn this month so far!

The session was started from the northeastern region in Hercules at 4:24 a.m. I happened to catch sight of a 3^m meteor flashing between Draco and the Great Dipper, toward NNW, by naked eye, at 4:33 a.m. 6-min later two open clusters OCL 167 and M29 successively passed by the FOV. In reality it was not an easy task to tell the difference from clusters and non-clusters as the stars are packed. The waning crescent moon rose above the small hill in the southeast at 5:20 a.m. I came across another open cluster NGC 6866 at around 5:35 a.m. Only two minutes later did Deneb entered the FOV near the edge, and 15-min later it made its second appearance. Twilight was brightening steadily, and I felt that this session was to end. Having completed the last downward sweep at 5:59 a.m., I concluded it. The crescent moon decorates the sky beautifully. What a fascinating scene!

Fri, Mar 08

Unexpectedly I managed to conduct one more comet hunt this predawn, thereby the third time this month. I had thought that the haze would dramatically worsen the sky but somehow it looked better than I had expected. Prior to the session I decided to observe comet 273P in Her first at around 4 a.m. I exerted myself to peering through the eyepiece which yielded 113x for me, trying to catch sight any hint of the dim blob of light. Admittedly I repeatedly saw something around the predicted position, however, I could not convince myself as it appeared too faint. Stars of around 12^m flickered in and out by the atmospheric turbulence. I felt that it was vain to further struggle. Then I took a look at the time. 'Oh man, already 4:49 a.m.! I have spent too much time attempting the observe comet 273P and probably won't have enough time for hunting!'

I quickly aimed the seeker to the region around θ Her and swept from there. The transparency below alt. 10° was horribly terrible due to haze and fog so I gave up searching regions below that elevation. Vega interloped into and dazzled the FOV at around 5:16 a.m. Around 5-min later, I noticed open cluster M29, not as impressive as I would imagine. All other deep-sky-objects I managed to pick up were only clusters, including NGC 6910 and NGC 7063. Vega entered the FOV for the second time at 5:30 a.m. I ended the session at 5:57 a.m. By the time the twilight had already turned relatively bright. The waning crescent moon graces the southeastern sky, shining gently, as it were speaking to me with full of emotion.

Thu, Mar 07

It is rare to witness clear weather in spring here normally, yet I unexpectedly had two consecutive clear predawn skies that enabled my comet hunts. Now the evening saw great haze, therefore, I do not think there will be any opportunity for meaningful comet hunt next predawn.

Yesterday, only until 4:49 a.m. did I start the session, sweeping from the region close to the border between Lyr and Her. The last-quarter moon posed some interference, but not serious. The schedule time was postponed since I had to settle down and check everything well for photographing comet 273P/Pons-Gambart. I did not intend to attempt to visually observe the comet as the time for sweep was already very limiting. At 5:06 a.m. I had to pause my search for awhile in that Astrotrac had to rewind. I serendipitously glimpsed a white flash at the region around 5° north to Saturn, as bright as Saturn, by naked eye, at 5:13 a.m. No motion, perhaps it was a meteor fleeting along my line of sight. Subsequently I resumed the hunting session. Anon, only 4-min later, renowned planetary nebula M57 entered my FOV. Albeit utilizing low power, only 30x, I was able to distinct it immediately from surrounding stars. The rim appears crisp and sharp. At 5:59 a.m. I happened to capture another satellite of around 1^m at peak, almost directly overhead, slowly moving from Oph to Her northwards. 7-min later, the session was ended.

This predawn at 4:30 a.m., I resumed sweeping from the azimuth where I completed yesterday. Unfortunately the transparency has worsened dramatically, particularly in low elevations. It was only 4-min later when M57 passed by the FOV near the edge. As star images are inferior around the edge, it was not very easy to spot such a tiny object. I was hesitated if I ought to spend some time observing comet 273P visually, but finally decided not.; twilight was to approach! Alas I did not pick up any other nebula any more during this session, which was put to an end at 6:00 a.m. As twilight brightened, I noticed that almost everything around me was saturated. How humid!

Fri, Feb 22

Today witnessed the first clear predawn since my last hunting session. Admittedly it was not totally free from clouds interference. In fact I was almost deceived by the cloudy southern sky through my windows if I had not peered through the window towards the north when I went to toilet. The northern sky was clear and extending eastwards! I swiftly carried the 8" seeker outdoors and immediately started the session from Hercules, somewhere close to Sarin, aka δ Her, at around 5:16 a.m.

As the humidity was very high, transparency in low altitudes was extremely poor. In relatively high altitudes, it was enjoyable to sweep across the field abundant with stars. At 5:56 a.m. an obvious fuzzy and comet-like bright object interloped into the FOV, against the rapidly brightening twilight. I did not carry the star atlas with me. I rechecked the area, evidently not and actually far away from M57. In my memory, there was no Messier object. New comet? Not that possible, I thought, because of its brightness, around 8^m. Nevertheless, I quickly ran indoors and then fleeted outwards back with my sketchbook and pen in hand. The bright stars around and the position of the object were roughly recorded. By the time when I completed it, the twilight had already been excessively bright. I looked at my watch, 6:16 a.m. 'Uhm, I need to verify it now', I thought. I took out the star chart and compare the star patterns against the chart bit by bit, and finally, the object was identified as M56, a bright globular cluster in Lyra. What a mistake! How come I could forget such a bright object! It well proved that I need far more practice.

Last Friday a meteorite fell in Chelyabinsk Oblast, Russia. The subsequent shock wave caused over 1,000 people injured, plus damages of many facilities and buildings. The criminal had not been discovered prior to the impact as it came from the direction of the sun, i.e. the elongation was too small. I am convinced that the majority of the surveys fail to cover regions at small elongations, and thereby there is some chance of discoveries for visual comet hunters. Diligence and industry are amongst the most cardinal factors and keys to success. I will be as patient as I can.

Thu, Jan 17

I managed to conduct the first comet hunting session in new year 2013 on Jan 14 predawn. Prior to the session, I quickly setup the equipment to photograph the rapidly brightening comet C/2012 F6 (Lemmon) low in the southern sky. As the region where the comet was placed was seriously light polluted by powerful road lights, therefore, I made no attempt to visually observe the comet through the 8" seeker. Frankly speaking I did not expect too much with my images either. However, after image processing, the outcome did surprise me.

By the way, before going to sleep, I observed and simultaneously photographed comet C/2012 K5 (LINEAR). It appeared evident at 30x, yet the tail seemed to elude me, despite that it was still bright in my photograph. On Jan 13.58 UT, m1 = 9.5, Dia. = 2'.1, DC = 3.

I commenced sweeping from ρ Boo at 4:34 a.m. Around 1-min's interval was spent to checking the status of my equipment at around 5:31 a.m. and I resumed the search from the area at which I paused. A fabulous fuzzy object interloped into the FOV at 6:13 a.m., which was immediately identified as globular cluster M13 in Hercules. I could not resolve any of the member stars at 30x, the power which I have been utilized for comet hunting, and therefore the object vividly appears as a bright comet. I went on to sweep, and finally concluded the session at 6:24 a.m.

Clouds prevailed the predawn sky on Jan 15 so there was no comet hunting session whatsover, whilst the evening was clear, only with some fog and high humidity. I observed comet C/2012 K5 (LINEAR) again on Jan 15 evening, which displayed an obvious fading. I was not allowed to perform a meticulous measurement of the size of the coma due to invasion of the clouds, size estimate only. On Jan 15.58 UT, m1 = 10.0, Dia. = 2', DC = 3.

Another session was conducted on the following predawn. I started the sweep at 4:33 a.m. from some degrees north away from ρ Boo. As M13 entered the FOV at 5:48 a.m., I deeply felt that the overlapping region was too large that I would have spent more time in sweeping new areas. However, I did not intend to change my sweeping path. 18-min later, the magnificent cluster revisited the FOV near the edge of the FOV. As twilight brightened swiftly, I ended the session at 6:21 a.m., without spotting any other truly fuzzy objects.

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