I drag myself out of bed again at 4:30 a.m. It's another very clear night, with limiting magnitude around 5.4 (using IMO method -- but this do not mean that tonight is better than last night, since last night I had to use a not-well located reference field as the cirrus block the favourite one). I get the 13-cm refractor out and set it up, but it takes me a little bit longer than last night to see the comet.

With a telescope, the sky quality seems to be slightly better than last night, the faintest star I have been able to see is TYC 6174-464-1 at 12.28 mag, but (26) Proserpina (12.5 mag) is still invisible. Galaxy NGC 5890 (at 12.6 mag) is only 10' away according to the map, unsurprisingly it's not visible, too. Tonight I have much more options on comparasion stars -- but the observation doesn't make me feel exciting. I estimate the total brightness of the comet to be around 7.3 mag using Morris method, with six comparasion stars at mag 6.17-7.97, while the coma diameter to be 7'. The comet's look does not change much except a 30" dense core run out tonight. Tonight's estimate is 0.5 mag fainter than that of last night, I think tonight's one is more reliable since only two comparasion stars were used last night.

Shortly before the astronimical twilight starts, I also give a try on NGC 5892, a galaxy about 3 degrees away at 12.0 mag, but with no luck. Seems its surface brightness is still too dim. I then shift back to Lulin and see it off in the twilight (still barely visible even after the nautical twilight started!).

I'm not sure when would the next dating occur. I'll be away for a three-week tour in the country soon, and the rainy season will begin at Guangzhou before I come back. I'll try if I can spot it with naked-eye when I arrive at Mt. Huangshan in mid Feburary.

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