* * * * * C/2006 P1 (McNaught) * * * * *

Year Mn Day MM Mag Ref Scope Pwr coma DC tail p.a. Obs Site 2007 6 12.42 S 10.3 GA 10.0B 25 SEA Cowra, NSW 2007 6 11.42 S 10.3 GA 10.0B 25 9 SEA Cowra, NSW 2007 6 9.48 S 10.1 AA 10.0B 25 8 0 SEA Cowra, NSW 2007 5 7.44 S 9.4 AA 10.0B 25 SEA Cowra, NSW (Appeared somewhat elongated with very faint tail suspected to, possibly, one degree.) 2007 4 20.40 S 9.2 AA 10.0B 25 SEA Cowra, NSW 2007 4 19.45 S 9.1 AA 10.0B 25 10 2 SEA Cowra, NSW (Seemed a little clearer thro' filter, especially toward the centre.) 2007 4 18.46 S 9.1 AA 10.0B 25 SEA Cowra, NSW 2007 4 17.42 S 9.0 AA 10.0B 25 SEA Cowra, NSW (Little different [poss. slightly fainter] thro' Swan Band filter.) 2007 4 16.38 S 9.0 AA 10.0B 25 4 SEA Cowra, NSW 2007 4 15.43 S 8.9 AA 10.0B 25 SEA Cowra, NSW (Little different thro' Swan band filter.) 2007 4 10.43 S 8.6 AA 10.0B 25 6 SEA The Entrance, NSW (Clearly brighter through Swan Band filter. Trace of tail visible.) 2007 3 27.75 M 8.1 AA 10.0B 25 1 SEA Cowra, NSW (Seemed a little clearer through Swan Band filter. Tail very faint to approx. 1 degree.) 2007 3 14.45 S 7.1 AA 3.5B 6 SEA Cowra, NSW (Tail visible for approx. 2 degrees naked eye with averted vision.) 2007 3 13.42 S 7.1 AA 3.5B 6 2.2 125 SEA Cowra, NSW (Tail still visible naked eye as a very faint sheath of light.) 2007 3 12.42 S 6.9 AA 3.5B 6 SEA Cowra, NSW 2007 3 11.44 S 6.7 AA 3.5B 6 SEA Cowra, NSW (In 25x100B, northern edge of tail more distinctly defined than southern edge. Coma enveloped in a very faint sheath which extended in direction opposite the tail.) 2007 3 10.45 S 6.6 AA 8.0B 15 SEA Cowra, NSW (Tail visible to naked eye as a very faint sheath of light.) 2007 3 9.42 I 6.4 AA 0.0E 1 10.0 SEA Cowra, NSW 2007 3 9.41 S 6.7 AA 3.5B 6 SEA Cowra, NSW 2007 3 8.42 S 6.8 AA 10.0B 25 7 6 2.0 SEA Cowra, NSW (Tail visible to approx. 4 degrees in 6x35 opera glass. Comet unchanged in Swan Band filter.) 2007 2 20.46 S 4.9 AA 5.0B 10 SEA The Entrance, NSW (From The Entrance, tail not visible in the light dome of Sydney.) 2007 2 14.45 B 4.1 AA 0.0E 1 26.0 SEA Cowra, NSW (Tail appeared as a broad fan with edges at p.a. 170 and 127 degrees. In 25x100B, broad anti-tail 12' long in p.a. 325 degrees.) 2007 2 13.45 B 3.9 AA 0.0E 1 SEA Cowra, NSW 2007 2 12.45 B 3.8 AA 0.0E 1 SEA Cowra, NSW 2007 2 10.46 B 3.3 AA 0.0E 1 SEA Cowra, NSW 2007 2 9.43 I 3.0 AA 0.0E 1 SEA Cowra, NSW 2007 2 8.45 I 3.2 AA 0.0E 1 SEA Cowra, NSW (Tail visible with naked eye for at least 30 degrees. Comet remained a striking naked-eye object. Magnificent in 25x100B.) 2007 2 7.45 I 3.0 AA 0.0E 1 SEA Cowra, NSW (Tail visible with naked eye for at least 30 degrees. Comet remained a striking naked-eye object. Magnificent in 25x100B.) 2007 2 6.44 I 3.0 AA 0.0E 1 SEA Cowra, NSW 2007 2 5.43 B 3.1 AA 0.0E 1 33.0 170 SEA Cowra, NSW (Tail length and p.a. is for the southern segment. The northern segment was measured as 9 degrees in p.a. 125 degrees. The central region of the fan appeared relatively dark in comparison with the edges, especially to within 2-3 degrees of the coma. After this, the southern segment seemed to diffuse across the central region and the tail appeared more uniform. In 25x100B, D = 6', DC = 8 and there was a broad anti-tail of 6' in p.a. 305 degrees.) 2007 2 4.42 B 3.2 AA 5.0B 10 SEA The Entrance, NSW (Tail a broad fan in binoculars, also glimpsed NE, possibly as long as 10 degrees.) 2007 2 3.42 B 3.1 AA 5.0B 10 SEA The Entrance, NSW 2007 2 2.44 B 2.4 AA 5.0B 10 SEA The Entrance, NSW (Brightness estimate may have been a little optimistic, as cirrus cloud anvils from dissipated thunderstorms made conditions difficult.) 2007 1 30.44 B 2.4 AA 5.0B 10 SEA The Entrance, NSW 2007 1 29.792 B 2.6 YG 5.0B 10 8 > 5 BOU Cape Town Airport, Western Cape, RSA (Comet observed behind hotel near airport with most of the lights shielded by buildings and trees. Comet still strongly condensed with broad fanshaped tail some 60 deg wide. The brighter, southern part of the tail could be followed over more than 5 degrees. Comp. stars were α Pav and γ Gru.) 2007 1 29.77 B 2.7 AA 5.0B 10 SEA The Entrance, NSW 2007 1 29.75 cI 2.5:AA 0.0E 1 SEA The Entrance, NSW (Estimates probably conservative due to morning twilight and thick haze. Approx. 3 degrees of tail visible through binoculars, but comet not easily visible naked eye in the haze.) 2007 1 28.795 B 2.5 YG 5.0B 10 8 BOU Noordhoek, Western Cape, RSA 2007 1 28.791 I 2.4 YG 0.0E 1 8 14 153 BOU Noordhoek, Western Cape, RSA (Comet observed at alt. 11.9 deg with Sun at -12.6 deg. Comp. stars were α Pav and γ Gru.) 2007 1 28.44 B 1.6 AA 0.0E 1 9 SEA The Entrance, NSW (Sky bright with moonlight and considerable light pollution from Sydney in region of comet. Several degrees of tail visible, but difficult to trace in the light sky.) 2007 1 27.799 aB 2.3 YG 5.0B 10 8/ BOU Noordhoek, Western Cape, RSA 2007 1 27.794 aI 2.2 YG 0.0E 1 8 16 150 BOU Noordhoek, Western Cape, RSA (Comet observed at alt. 11.0 deg with Sun at -13.1 deg. Comp. stars were α Pav and γ Gru.) 2007 1 26.790 aI 2.0 YG 0.0E 1 8 19 145 BOU Noordhoek, Western Cape, RSA (Comet observed at alt. 11.1 deg with Sun at -12.1 deg. Comp. star was α Pav.) 2007 1 26.44 cB 0.8 AA 0.0E 1 9 32 135 SEA The Entrance, NSW 2007 1 25.795 aI 1.4 YG 0.0E 1 8 20 143 BOU Noordhoek, Western Cape, RSA (Comet observed at alt. 9.7 deg with Sun at -13.2 deg. Comp. stars were α Pav and α Gru. Slightly curving tail can still be followed beyond α Tuc, but most of the fainter parts of the tail and strucure is now lost due to moonlight interference.) 2007 1 24.787 aI 1.3 YG 0.0E 1 8 20 140 BOU Yzerfontein, Western Cape, RSA (Comet observed at alt. 10.1 deg with Sun at -11.2 deg. Comp. stars were α Pav and α Gru.) 2007 1 23.793 aI 1.0 YG 0.0E 1 8 20 135 BOU Yzerfontein, Western Cape, RSA (Comet observed at alt. 8.2 deg with Sun at -12.7 deg. Comp. stars were α Pav and α Gru.) 2007 1 22.789 aI +0.8 YG 0.0E 1 8 25 128 BOU Harmon, Western Cape, RSA (Comet still very impressive. Estimate was made with comet at alt. 8.2 deg with Sun at -11.7 deg. The tail is longer than 3 days ago, but increasing lunar interference considerably reduced visibility of the fainter NE streching part of the tail. In 10x50B still numerous synchrones can be seen, but they are becoming more diffuse and broader now. Comp. stars were α Pav, α Cru and β Cru.) 2007 1 22.42 cI 0.0 AA 0.0E 1 9 20 SEA The Entrance, NSW (Very poor conditions, but tail still visible high into Grus.) 2007 1 20.42 cI -0.5 0.0E 1 9 SEA The Entrance, NSW (Bright curving tail extended to near α Gruis, before turning at almost right angles and extending beyond Formalhaut. Striae clearly visible with naked eye and very obvious in 10x50B, as were the obvious dark 'lanes' betwen the striae. A very prominent one was noted with the naked eye in Grus, appearing rather like a stationary auroral beam. Main comparison for brightness was α Cen. taken as mag. -0.3.) 2007 1 19.785 aI -0.2 YG 0.0E 1 8 17 132 BOU Pearly Beach, Western Cape, RSA (Comet now is really an impressive view. Estimate was made with comet at alt. 5.9 deg and Sun at -10.4 deg. Tail details were recorded 40m later. The length and p.a. were measured on this, and all following dates, along the brighter part of the tail to the point of greatest length. To the naked eye the slightly curving tail showed many synchrones or striations, stretching NE almost to Fomalhaut [and on the 20th well past it, reaching a length in that direction of some 40 degrees.]. In 7x50B the amount of detail in the tail was really spectacular, and virtually beyond description; the head was nearly stellar, the tail being an almost 90 degrees fan, far brighter on the southern edge. Comp. stars were α and β Cen. Extinction corrections on this and following dates were made with the 'average' ICQ table.) 2007 1 19.43 cI -1.0 AE 0.0E 1 9 SEA The Entrance, NSW (Tail appeared strongly curved with striae clearly visible to the naked eye. The tail could easily be traced for at least 15 degrees into Grus, where it seemed to merge into a band of light lying parallel to the horizon and extending for another 15 degrees through Piscis Austrinus. Initially, this was thought to be a band of atmospheric haze, however it proved to be a continuation of the tail [which had made a 90 - degree turn!]. The full visible tail length was therefore at least 30 degrees.) 2007 1 18.41 cI -2.0 AE 0.0E 1 9 10 125 SEA The Entrance, NSW (Very spectacular in twilight! Tail curved like a scimitar or quill, curving to around p.a. 60 deg at the extremity. The tail remained visible long after the head had set.) 2007 1 17.764 I -2 :AE 0.0E 1 8/ > 1 BOU Pearly Beach, Western Cape, RSA (Comet seen in strong twilight between clouds, with comet at alt. 7.5 deg and Sun -5.0 deg. Clearly fainter than Venus, although both objects could not be seen simultaneously. Comet small and strongly condensed with bright tail disappearing in cloud.) 2007 1 17.45 I -3.3 AE 0.0E 1 9 SEA The Entrance, NSW (Seen amongst cirrus cloud. Bright tail over 1 degree long seen projecting from cloud after head became hidden.) 2007 1 16.41 cI -3.5:AE 0.0E 1 9 2.0 SEA The Entrance, NSW (Tail appeared delicately curved. Comet appeared yellow-orange in colour in 25x100B and even to naked eye.) 2007 1 15.510 S 2 :AE 12.0B 20 3 8 LOO Botrange (Observation in daylight at noon. Comet definitely 1, probably 2 magnitudes fainter than Venus. Location in Ardennes at +680m. Very clear sky with some contrails.) 2007 1 15.38 cS -4.3 AE 5.0B 10 9 SEA The Entrance, NSW (Comet was earlier located for a short time some five hours prior to sunset [Jan. 15.18 UT] with 10x50B, as a 'soft' star-like object with a short tail. No estimate could be made at that time. For the estimate given, Venus was placed very slightly out of focus.) 2007 1 14.71 !I -6 :AE 0.0E 1 8 1.5 50 GON Colunga, Asturias (Comet observed from near sea level, just before sunset; alt. 2.2 deg.) 2007 1 14.59 !I -4.6:AE 6.3B 9 0.5 8/ 0.15 90 DAH Blindern, Oslo (The comet was first located in 9x63B at 13h45m in broad daylight, shortly after emerging from clouds, and followed until disappearing in low clouds at 14h45m, around the time of sunset. The comet was easily visible when using nearby buildings to shield the sun, but was not firmly detected with the naked eye. Clear sky near the comet, the formal estimate was made at altitude 3.0 deg and solar alt. 2.2 deg [14h10m]. It was estimated as 1.0 mag fainter than Venus [alt. 9.9 deg.] and the deduced m1 magnitude has been corrected for extinction by using a coefficient of 0.2 mag per airmass. The central condensation was intense and almost stellar in appearance. The coma and tail had a white color when first spotted, but the color became more yellowish as the comet moved lower in the sky. The tail had a V-shape with a somewhat larger opening angle than two days ago.) 2007 1 14.58 I -4.5:AE 5.0B 7 9 0.1 95 GRA Fjellhamar (When first seen [13h55m] the comet was a quite easy object in 7x50B, but it was not seen naked eye. Its tail appeared wide and was only seen with difficulty. The comet was detected a few minutes after it emerged from clouds [the sky was about to clear]. Formal observation [around 14h00m] was obtained at true altitude 3.6 deg and solar altitude 2.8 deg. The magnitude estimate is uncertain as Venus was hidden behind clouds, but the comet's visibility was quite similar to my Jan 13.36 observation, as well as that of Venus during my small solar elongation observations of this planet [e.g. around its inferiour conjunction in 2004]. The comet was last seen at 14h36m [8 minutes after local sunset and a few minutes before it set] at altitude 1.0 deg, it was then a more challenging object. The comet was also briefly seen in 7.0-cmR at 32x; here its pseudo-nucleus appeared similar in size to the Venus' disk [0'.2]; the comet was, however, easier to detect in binoculars.) 2007 1 14.53 B -4 :AE 25.6L 84 0.4 8 BIV Versailles (Day-time observations in the 25.6-cmL [42x and 84x] with interfering cirrus [bright background]. Rough comparison to Venus.) 2007 1 14.38 cI -5.2 AE 5.0B 10 9 SEA The Entrance, NSW (Comet initially located about 10 minutes before sunset with 24x100B and quickly located in 10x50B and 2.5x25B. It was seen naked eye about the time of true sunset, although the sun was already disappearing behind a range of distant hills.) 2007 1 14.32 I -5.2:AE 7.0R 10 8/ &0.2 65 YOS Toride City, Ibaraki (Today we could have another fine day. Although the sky was a bit hazy and not very clear, I could see Comet McNaught shining gold in the twilight at the sunset time. Incredible, but I could find it when Sun was still over the horizon. It was almost daytime. People were driving cars without switching the lights. Comet McNaught was easy to see, but it took some more time to find Venus. It means Comet McNaught has become really brighter than Venus. Comet McNaught looked sharp sparkling stellar. Now the tail became wide and somewhat curving. Comet McNaught had been visible for 10 minutes. It was very fantastic and impressive to see bright comet shining among beautiful clouds reflecting evening light, whose color was changed from gold to madder red. Using the winter extinction table, the brightness of Comet McNaught was estimated as about -5.2 mag. What an incredible result!) 2007 1 13.53 I -5 :AE 5.0B 7 8/ 0.3 SKI Hønefoss (The comet was easily seen in 7x50 binoculars despite its small solar elongation. C/2006 P1 showed a fan- shaped tail that appeared brighter at its wings. Formal observation was made at 12h45m at altitude 10.4 deg and solar altitude 6.8 deg. The magnitude estimate is uncertain as Venus was hidden behind clouds, but the visibility of the comet was somewhat better than Venus when this planet was seen in 7x50B at similar solar elongations. The comet was seen from 12h30m and until clouds arrived at 13h45m.) 2007 1 13.36 7.0R 32 1 8/ 0.1 50 GRA Fjellhamar 2007 1 13.36 !I -4.7:AE 5.0B 7 9 0.1 50 GRA Fjellhamar (The comet was easily seen in binoculars, but not detected with naked eye. This observation was affected by high clouds but the comet was seen in clear gaps for a few minutes between 08h32m and 08h46m. Formal observations were obtained around 08h44m at altitude 3.9 deg and after local sunrise at altitude 2.2 deg, but the Sun was then greatly dimmed by the clouds. The magnitude estimate is uncertain as no suitable comparison objects were available at the time of observation, but Venus appeared somewhat brighter [about 0.5 mag.] when it was seen later this day at 13h50m [alt. 10 deg]. The deduced m1 magnitude has also been adjusted for extinction by using a coefficient of 0.20 mag per airmass. The m1 estimate, however, appears to be reasonable when compared to my previous observations of Venus obtained under similar solar elongations. In 7.0-cmR at 32x, the comet showed a nearly stellar bright false nucleus [dia. 0'.2 or less], plus a coma and a short and parabola shaped wide tail that appeared faint under these conditions. An attempt to observe the comet later this day [from Blindern, Oslo] around the time of the Venus observation was unsuccessful due to incoming front clouds.) 2007 1 12.73 $I -3.2 AE 0.0E 1 9 1 35 GON Alto del Castro, León 2007 1 12.73 $I -3.2 AE 10.0B 25 0.7 8/ 1 35 GON Alto del Castro, León (Mountain location, very clear sky [strong zodiacal light visible after the end of twilight]. Magnitude estimate corrected for atmospheric extinction with ICQ winter table [comparison object: Venus]. Alt. 3 deg. Solar elongation: 7 deg. The comet remained visible for 35 minutes until it set behind the horizon.) 2007 1 12.57 B -3 :AE 25.6L 84 0.2 8 BIV Versailles (Day-time observations in the 25.6-cmL [42x and 84x] with interfering cirrus [bright background]. Rough comparison to Venus.) 2007 1 12.34 !I -3.3:AE 6.3B 9 0.5 8/ 0.2 30 DAH Fjellhamar (Clear sky. The formal estimate was made 08h13m, close to the time of sunrise [the true solar altitude was -0.4 deg]. The m1 magnitude was estimated as 0.6 mag brighter than Jupiter and the deduced value has been obtained by using an extinction coefficient of 0.20 mag per airmass. C/2006 P1 comet was observed at altitude 4.4 deg on a very bright sky background, shortly after emerging from trees. Once located, the coma and inner tail were quite easily visible in binoculars, but the comet could not be firmly detected with the naked eye. The tail had a V-shape, its outer edges being brighter than the region in the middle. I was not able to see the comet in binoculars after 08h30m.) 2007 1 11.75 aM -3.5:AE 3.4B 9 & 3 7 & 1 15 PER Cabo da Roca 2007 1 11.75 aI -3.5:AE 0.0E 1 8 & 1 PER Cabo da Roca (Observed from sunset until true solar altitude -5.4 deg; comet true altitude varied between 7.1 and 2.7 deg.; reported m1 is representative of several estimates [each corrected for differential extinction with the exact true altitudes for each observation time] which agreed to 0.3 mag; used ICQ average atmospheric extinction table, which I felt was more adequate to the actual sky conditions. Comparisons with Venus and α Aquilae. In 9x34B: parabolic coma and prominent hollow in tail; in 14x100B's: hint of parabolic "shells" in coma similar to those observed in C/1995 O1.) 2007 1 11.73 !I -2.5:AE 0.0E 1 9 1 10 GON Villalverde, Zamora 2007 1 11.73 !I -2.5:AE 10.0B 25 1 8/ 1 10 GON Villalverde, Zamora (Mountain location. Magnitude estimate corrected for atmospheric extinction [comparison object: Venus]. Alt. 3.5 deg. Solar elongation: 9 deg. Upper section of the curved dust tail obscured by cirrus clouds. The comet remained visible for 25 minutes in nautical and astronomical twilight until it set behind the horizon.) 2007 1 11.68 $S -3.0:AE 0.6E 1 0.5 8 2.0 10 GIL Noordwijk aan Zee (29 minutes after sunset. Altitude Sun -4.3 deg, comet +4.7 deg. Compared with Venus; corrected for extinction using ICQ summer table [humid conditions]. Strong wind [8-9 Beaufort].) 2007 1 11.674 wM -3.3:AE 5.0B 7 9 4 8 DIJ Oude Schip (Finally my second observation of this comet after a brief glimpse between clouds on Jan. 5 around 6h48m UT. Today the comet could be observed under excellent, but windy conditions from 16:01 to 16:18 UT, when clouds started interfering again. Brightness estimate was made at 16:11 UT with Venus as comparison. Corrected for extinction with ICQ winter table.) 2007 1 11.673 aM -2.8:AE 5.0B 7 8 & 1 15 BOU Noordwolde (Comet observed in brief clearing under very windy conditions. Easy object in strong twilight. Comet 4.5 deg above horizon with the Sun 4.6 deg below it. Compared with Venus at 6.7 deg altitude. Corrected for extinction using ICQ average table. Comet had a strong yellow-orange hue, quite a contrast to blueish-white Venus.) 2007 1 11.67 $S -2.8:AE 5.0B 10 0.5 9 3.0 10 GIL Noordwijk aan Zee (24 minutes after sunset. Altitude Sun -3.7 deg, comet +5.5 deg. Compared with Venus; corrected for extinction using ICQ summer table [humid conditions]. Strong wind [8-9 Beaufort]. Tail looked more evenly illluminated than yesterday, although split could still be seen.) 2007 1 10.98 w -3.3: 5.0B 10 MAR St. Louis, MO (Short tail. 23:33 UT, comet alt 2.0 deg, Altair alt 17.1 deg, ICQ winter extinction correction. Comet visible to naked eye 14 min before Altair.) 2007 1 10.71 $B -2.6:HV 5.0B 7 0.5 9 BIV Versailles 2007 1 10.67 &S -2.4:AE 5.0B 10 0.5 8/ 2.0 5 GIL Noordwijk aan Zee (21 minutes after sunset. Altitude Sun -3.4 deg, comet +7.1 deg. Compared with Venus [alt. + 7.7 deg, magn. -3.9]. Observed between clouds with very strong wind. Tail looked split like the trails of a high flying airplane. Before I could make a naked eye estimate, sky went completely covered with clouds.) 2007 1 10.65 !B -2.9 0.7E 1 2 9 4 0 GUZ Krakow (The conditions were excellent - I could very clearly see Tatra mountains which were ~90km from my location. The comet was awesome sight. The tail could be traced AT LEAST to 4 degrees both with binoculars and with naked eye. It had extremely high surface brightness. It was curved to west and its eastern border was much more pronounced than western. I could still see it for several minutes after the comet had set behind the hills at true altitude 2.0 deg. It was also easy to see "nucleus shadow" through binoculars. Comet at first was perly-white and later became golden, thus the colour is an atmospheric effect. I used Venus and Altair to estimate comet's brightness. The observation is corrected for atmospheric extinction with a parameter of 0.15 mag per airmass as the sky was extremely transparent.) 2007 1 10.59 B -2.5: 5.0B 10 0.5 9 0.1 0 GUZ Krakow (I found the comet around 14:05 UT - when the Sun was 5.9 deg above horizon. The comet was pretty well visible with handheld 10x50B. I could even spot ~5' of tail. Then I estimated its magnitude simply comparing with Venus.) 2007 1 10.34 wI -2.2:YG 7.0R 10 8/ 0.3 15 YOS Toride City, Ibaraki (The sky was fine with no clouds. Although the sky was not so excellent, comet McNaught was easily visible with 10x70 monocular, with a sharp sparkling stellar head and a tail toward upper-right direction. It was visible for 20 minutes. I estimated it when the Sun located 5 degree below the horizon. Comet McNaught was brighter than 1-mag star Altair locating higher than the comet. It was a fantastic view to see a comet in the twilight color sky. It was very different from usual comet observations. Using the winter extinction table, the brightness was estimated as -2.2 mag. It is brightest in my life, brighter than Comet Hyakutake or Comet Hale-Bopp.) 2007 1 10.31 !I -2.6:AE 0.7E 1 9 GRA Fjellhamar 2007 1 10.31 !B -2.6:AE 5.0B 7 1 8/ 0.5 10 GRA Fjellhamar (In 7x50B the comet was seen for 43 minutes until 07h43m [at solar altitude -3.4 deg] when disappeared behind clouds. The comet was seen with naked eye [until 07h39m], despite bright sky and interference from clouds. This observation was hampered by high clouds, but the conditions were reasonably good when I made the formal m1 estimates at 07h26m. The comparison object was Jupiter. H. Dahle's and my m1 observations have been extinction corrected by using a coefficient of 0.20 mag per airmass.) 2007 1 10.31 !I -1.8:AE 0.7E 1 9 0.7 DAH Fjellhamar (Mostly cloudy sky, with a clear gap low towards the horizon where both the comet and Jupiter [the comparison object] could be seen. The formal observation was made at 07h26m, with the comet 4.3 degrees above and the sun 5.0 degrees below the true horizon. The comet was an easy naked eye object, and the tail was also quite easily visible. The tail length was difficult to estimate as the far end of the tail was obscured by clouds above the comet, and the tabulated value can be regarded as a lower limit. In 20.3-cmT at 133x on Jan. 10.32, the pseudo- nucleus appeared stellar [in poor seeing], surrounded by a very bright inner coma of fairly uniform surface brightness, but brightening gradually towards the nucleus; the edge of the coma was very sharply defined in the solar direction; the coma and inner tail had a distinct yellow color.) 2007 1 9.98 wI -2.9: 0.7E 1 MAR St. Louis, MO (Short tail. 23h 30m UT, comet alt 2.8 deg, sun alt -6.5 deg, comet visible ~10 min before Altair [alt 18.4 deg], ICQ winter extinction corrections, averaged comparison with Venus [alt 8.2 deg] and Altair.) 2007 1 9.72 -2.1: 5.0B 7 0.5 1.5 BIV Meudon 2007 1 9.71 -2.2: 0.7E 1 1 1.5 BIV Meudon Preliminary report: (Tonight we were lucky to get relatively clear skies to the horizon with good transparency [only scattered stratus like clouds]. I observed the comet from the top of Meudon Observatory Solar Tower [360o clear horizon]. The comet was seen naked eye from 16:39 to 17:15 UT [Sun alt. -4.5 to -9.5 deg]. Each observation is an average of two estimates using atmospheric correction with winter table. Comparison stars were Vega, Deneb, Altair, γ, β and δ Aql, but otherwise the comet looked [at least] 2 magnitudes fainter than Venus 2 deg. higher in the sky. The estimates are very dependent on the assumed atmospheric extinction, probably overestimating a bit. In addition the comet was observed in the 25.6-cmL at 169x at 16:35 UT with not bad seeing [much worse on Jan. 7.3 and 30min later] but windy. The inner bright core is less than 6" accross and the [parabolic] coma shows a very straight edge 0.6' in the Sun direction. It seemed to me that in between 3 arcs/shell-like structure [like in Hale-Bopp in 1997] were visible.) 2007 1 9.67 6.3B 9 0.6 8/ 4 15 DAH Blindern, Oslo (With 9x63B, the coma had a parabolic shape, and the coma and inner part of the tail had a very distinct golden yellow hue; the tail curved clockwise and remained visible in binoculars and to the naked eye for at least 10 minutes after the head had set in clouds [16h04m]. The observation was at true altitude 2.0 deg and solar altitude -9.7 deg [16h03m].) 2007 1 9.66 5.0B 7 1 2 SKI Hønefoss 2007 1 9.66 wI -2.3:YG 0.7E 1 8/ 2 SKI Hønefoss (With naked eye, formal observation was made at altitude 3.8 deg and solar altitude -8.0 deg [15h50m]. The comet was seen 0.4 mag fainter than Vega and 0.7 mag brighter than Altair, it was observed from 15h34m and until it set behind clouds [16h06m].) 2007 1 9.66 !B -2.4:YG 5.0B 7 1 8/ 3 15 GRA Nyland, Oslo 2007 1 9.66 !B -2.3:YG 0.7E 1 9 2 GRA Nyland, Oslo (The m1 estimates were made around 15h44m [altitude 4.5 deg. and solar altitude -7.4 deg.]. C/2006 P1 was seen from 15h24m and until it set behind clouds [16h06m], but the comet was hidden behind clouds for much of this interval. The clear parts also appeared less transparent than on Jan. 8.66, the comet, nevertheless, was seen somewhat brighter. In calculating the m1 values I have used an extinction coefficient of 0.25 mag per air mass [the comet appeared equal in brightness to both Venus at alt. 2.0 deg and Vega at alt. 39 deg]. Observed from my work location.) 2007 1 9.65 !I -2.5:YG 0.7E 1 9 1.5 15 DAH Blindern, Oslo (With naked eye, the magnitude estimate was obtained quite early [15h33m], although with the comet easily visible on a bright sky background, to minimize the value of the extinction correction, altitudes of comet and Sun were 5.6 and -6.3 deg respectively. Later, at 16h10m, the tail length was estimated as 3.5 degrees by naked eye, although the tail was only visible in segments between clouds at any given time. Partially cloudy sky, with very clear sky in gaps between clouds. The comparison objects were Venus and α Aql.) 2007 1 8.67 !B -1.4 YG 6.3B 9 0.7 8/ 2.3 0 DAH Tryvann, Oslo (The formal magnitude observation was made at 15h35m [altitude 5.8 deg and solar altitude -6.6 deg] and soon after local fog had lifted at the observing site and revealed the comet as an easy naked-eye object in a very clear sky. The m1 estimate was obtained as early as possible to minimize the value of the extinction correction. The coma appeared 0.1 mag fainter than Vega and 1.0 mag brighter than Altair. Later, at 16h08m, the tail length was estimated as 1.5 deg by naked eye. Around this time, the comet was the most striking naked eye object in the evening sky.) 2007 1 8.66 !I -1.1 YG 0.7E 1 9 1.5 DAH Tryvann, Oslo (The observation [16h05m] was made when the comet was at true altitude 2.5 deg and with the Sun 9.8 deg below the horizon. The coma and inner part of the tail had a very distinct yellow-orange hue, and the central condensation was nearly star-like and extremely intense. The tail was broad and slightly curved. More than a degree of tail remained easily visible in binoculars after the head of the comet had set in low clouds [16h28m], a few arcminutes above the true horizon [the observation was made from a site of elevation 500 meters with a clear view of the western horizon]. The sky was very clear near the comet. The m1 estimates were 0.7 mag fainter than Vega and 0.2 mag brighter than Altair.) 2007 1 8.66 !B -0.9 YG 5.0B 7 1.5 8/ 3.0 5 GRA Nyland, Oslo 2007 1 8.66 !B -1.0 YG 0.7E 1 9 3 GRA Nyland, Oslo (With naked eye, the comet was very easily seen from 15h40m [solar altitude -7.2 deg] and until it set 35 minutes later [at true altitude 1.2 deg], it showed an apparently stellar coma and an easily seen tail; its brightness was comparable to a magnitude +1 star under a dark sky and clearly superiour to Mercury during its most favourable maximum elongations; the m1 magnitude was estimated as 0.6 mag fainter than Vega and 0.4 mag brighter than Altair. With 7x50B, the comet was distinctly golden yellow in colour; and showed a nearly stellar central condensation and a tail that was moderately broad and slightly curved clockwise; the tail was bright for the first degree and its edges were notably brighter than the region in the middle; the m1 estimate was 0.3 mag brighter than Altair and 0.7 mag fainter than Vega. The formal magnitude estimates were made at 15h51m at altitude 3.9 deg and solar altitude -8.3 deg; the deduced magnitudes have been corrected for extinction by using a coefficient of 0.15 mag per airmass [the sky was very transparent]. This observation was made from my work location.) 2007 1 8.65 !I -0.8:YG 0.7E 1 8 1.5 SKI Hønefoss (The m1 was made 15h40m [altitude 5.4 deg and solar altitude -7.1 deg.], then the coma appeared 0.5 mag. brighter than Altair, but much fainter than Venus. The tail curved somewhat and was also seen for 1.5 deg. in 7x50B. The comet was observed from 15h30m and until the coma set at 16h10m, while the tail could be followed for a further six mimutes. The sky was very transparent.) 2007 1 8.65 !B -1.5: 5.0B 10 1 8 2 0 GUZ Krakow (The magnitude is not as certain as that made in the morning because the only comparison was Venus. Comet was seen for 10 minutes [15:30-15:40UT] through thin cirrus between more dense clouds. Though through cirrus it was still visible with naked eye pretty easily. Even 15' of tail was seen with naked eye.) 2007 1 8.30 $B -1.5:TI 0.0E 1 & 2 8 &0.5 RES Szamotuly-Galowo (Easy naked eye object. The brightest part of the tail [about 10-15'] was also barely visible by NE. Comet altitude 3.1 deg. Magnitude extinction [winter table] calculated using following parameters: For comet: extinction=3.56 mag, alt. 3.1 deg; for α Aql: Vmag=0.76, extinction=1.00 mag, altitude=13.78 deg; for γ Aql: Vmag=2.72, extinction=0.87 mag, altitude=15.85 deg. Coma has beautiful yellowish color, very gentle in view. Central condensation looks like diamond in it. Tail in binoculars about 0.5 deg, slightly fan shaped.) 2007 1 8.24 !B -0.8 TK 5.0B 10 1 8 2 0 GUZ Krakow (This morning I observed the comet from Krakow (Poland) for about 45 minutes. I caught it with 10x50B about 5:40UT as it was emerging from layer of fog at true altitude 1.4 deg. Few minutes later [~5:45UT] I could see it with naked eye. When it came slightly higher I started to estimate its brightness. Comparison stars were α Aql [+0.9], β Aql [+3.8] and γ Aql [+2.7]. I made 4 estimations between 5:52 UT - 6:01 UT getting m1 for the comet equal to -0.8 mag each time. All observations were corrected for atmospheric extinction assumed to be 0.21 mag per airmass. I guess the magnitude may be slightly underestimated as comparison stars were at definitely darker sky than the comet. Pseudonucleus was golden and brilliant - I estimated m2=0.0: The tail has high surface brightness and with binoculars I could see it about 2 degrees long. First 15' was also visible to unaided eye. I could see the comet with naked eye till 6:12 UT when the Sun was only 4.3 deg below horizon and comet 6.2 deg above horizon. Then I could still see it with 10x50B till 6:25 UT [Sun only 2.5 deg below horizon]. I would see it probably for few minutes more but I moved to another place and couldn't locate it again.) 2007 1 7.30 $B 0.0:HV 5.0B 7 1.0 8 0.4 0 BIV Meudon (Comet observations from Meudon observatory, seen with naked eye; many interfering cirrus clouds but comet easily seen from 6:50 [alt. 2 deg.] to 7:15 UT; 1' coma with 0.25 deg tail with parabolic shape in 25.6-cmL at 42x; Comparison stars: α and γ Aql, higher in a darker sky; comet probably even brighter than m1=0 given that it was more easily seen naked eye than Altair at same elevation earlier.) 2007 1 6.68 !M -0.3:YG 6.3B 9 0.3 8/ 0.8 0 DAH Holmenkollen, Oslo 2007 1 6.68 !I -0.3:YG 0.7E 1 9 DAH Holmenkollen, Oslo (With naked eye the formal observation [16h13m] was made when the comet emerged in a clear gap below clouds at true altitude 1.8 deg and solar altitude -11.2 deg; the comet was clearly visible but no tail was seen; it remained visible without optical aid until its altitude was 0.5 deg [16h24m]. With 9x63B the observation was made at altitude 1.5 deg [16h15m]; the coma and inner part of the tail had a very distinct yellow-orange hue, and the innermost 0.2 deg of tail had a very high surface brightness; the tail was V-shaped, its edges being brighter than the region in the middle, broad and slightly curved; the tail remained visible in binoculars for more than a minute after the head of the comet had set in low clouds [16h28m]. The observation was made from a site of elevation 400 meters with a clear view of the western horizon and the sky was very clear near the comet. Comparison stars were γ Cyg and ε Cyg.) 2007 1 6.28 !I 0.2:YG 0.7E 1 GRA Tryvann, Oslo 2007 1 6.28 !B 0.2:YG 5.0B 7 1 8/ 1 0 GRA Tryvann, Oslo (The comet was easily visible with naked eye, it was almost as well seen as Mercury at its best from this latitude. Through 7x50B it showed a bright stellar nucleus and an easily visible tail. Formal observation was made at altitude 2.5 deg and solar altitude -10.5 deg. The comparison star was α Aql and the comet appeared approx. 1.0 mag. fainter than this star, the deduced m1 magnitude is corrected for extinction by using an extinction coefficient of 0.15 mag per airmass. My observation was somewhat uncertain as most of the sky was covered by clouds, but the m1 estimate should be fairly reliable as Jupiter [seen somewhat earlier at alt. 4 deg.] appeared much brighter [2-3 magnitudes] than the comet. The comet was seen for about 25 minutes before it disappeared behind the cloud layer. This observation was made from an elevation of about 500 meters, fog prevented observing from lower elevations. During this and the previous morning the comet was also imaged using a digital SLR [Canon EOS 400D] and 100-mm FL lens.) 2007 1 5.29 !M 1.4 YG 6.3B 9 0.6 8/ 0.8 355 DAH Fjellhamer 2007 1 5.28 !B 1.3 YG 5.0B 7 1.5 8 0.8 0 GRA Fjellhamer 2007 1 5.28 !I 1.3 YG 0.7E 1 GRA Fjellhamer (The comet was seen without optical aid from 06h17m [at altitude 0.5 deg, 1-2 minutes after it rose above the local horizon] until 07h15m; it was a rather easy naked eye object until a solar altitude of -7.5 deg. In 7x50B , the comet showed a yellow-orange hue and a small coma with an apparently stellar central condensation [mag. about 1.5], plus an easily visible and U-shaped tail. This observation was made under a very transparent sky. Formal m1 observations were made at altitude 4.4 deg and solar altitude -9.1 deg; the principal comparison star was &eta Oph;. I was observering from a site [elevation 250 meters] with a clear view towards SE and about 1.5 km from H. Dahle's location. The magnitudes for this and the other Jan 5-6 observations by Dahle and myself were deduced by using an empirically determined extinction coefficient of 0.15 mag per airmass.) 2007 1 5.28 !I 1.1 YG 0.7E 1 9 0.2 355 DAH Fjellhamer (With naked eye the formal observation [06h45m] was made when the comet was at true altitude 3.8 deg and with the Sun 9.6 deg below the horizon; the comet was easily visible as a stellar object, with a faint, short tail, and it remained visible without optical aid until a solar altitude of -6.4 deg [07h15m]. In 9x63B, the m1 observation was made at altitude 5.0 deg and solar altitude -8.5 deg [06h56m]; the coma and inner part of the tail had a distinct yellow-orange hue; the coma had the appearance of a small disk of almost uniform surface brightness, rather similar to a planetary disk; the tail was fan-shaped and easily visible. Exposures with a Nikon D70 SLR and 300-mm f/5.6 lens gave a good impression of its appearance through binoculars. In 20.3-cmT at 80x on Jan. 5.29, the coma appeared as a yellow-orange disk, slightly smaller than Jupiter, and the innermost 0.25 deg of tail was very obvious; the seeing was poor. Comparison stars were α Aql and γ Aql.) 2007 1 5.24 !B 1.0 TK 5.0B 10 2 8 0.5 360 GUZ Krosno (The comet was very bright and easily visible against bright sky. I could see it for fifteen minutes [5:35 - 5:50 UT], when it was situated between clouds on very transparent sky. It was planet-like object with broad dust tail. First 10' of the tail were very bright. It was also faintly seen with naked eye. Comparison stars were α Aql [+0.9] and λ Aql [+3.4]. Magnitude was corrected for atmospheric extinction using extinction parameter equal to 0.21 mag per airmass.) 2007 1 4.65 wI 1.0:TK 0.7E 1 9 DAH Blindern, Oslo (The comet was faintly visible to the naked eye and had a star-like appearance. The comparison star was γ Aql, but the m1 magnitude is highly uncertain due to the difficult conditions.) 2007 1 4.64 wI 2.0:TK 6.3B 9 0.5 8/ 0.1 0 DAH Blindern, Oslo (With 9x63B, the formal observation [15h28m] was made when the comet was at true altitude 6.5 deg and with the Sun 6.8 deg below the horizon. The comet was easily seen, but only for a short period [15h25m-15h30m], in a narrow clear gap between clouds. The coma had an almost stellar appearance, and a short, fan-shaped tail was visible, pointing due north. The deduced m1 magnitude is highly uncertain, as the sky was almost completely overcast, and no suitable comparison stars were available at the time of observation. However, about five minutes later, a comparison star [β Aql] was seen through another cloud gap.) 2007 1 3.28 wS 1.5 TK 6.3B 9 1.7 8 0.2 DAH Fjellhamer (The formal observation [06h43m UT] was made when the comet was at true altitude 3.9 deg and with the Sun 9.9 deg below the horizon. Once located in binoculars, the comet was fairly easily visible to the naked eye as a stellar object with no apparent tail. A short, fan-shaped tail was visible through binoculars. The deduced m1 magnitude has been corrected for extinction using the "winter" extinction table of ICQ, Vol. 14, pp 55-59 (1992). The comparison stars were γ Aql and β Aql. A couple of 1s exposures, taken with a Nikon D70 SLR [300mm f/5.6 lens, ISO 800], gave a good impression of the appearance of the comet through binoculars.) 2007 1 2.30 $B 2.7 TK 10.0B 25 1.5 8 0.1 0 GON Alto del Castro, León (Mountain location, clear sky. Magnitude estimate corrected for atmospheric extinction with ICQ winter table. Very low altitude: 3 deg; solar elongation: 15 deg. Short dust tail. The comet remained visible for 15 minutes in nautical twilight.) 2006 12 29.28 !M 3.9 TK 10.0R 25 1.5 7/ GRA Fjellhamar (The comet showed a coma with an almost stellar false nucleus [approx. 15" in size] of magnitude 4.7 [ref TK]. This bright spot was surrounded by a fainter diffuse glow. Formal observation [06h45m UT] was made a few minutes after the comet was first seen and obtained at true altitude 3.6 deg and with Sun 9.8 deg below the horizon. The coma was quite easily seen despite these challenging circumstances, and it appeared notably less red than the nearby K3III star α Sct. It was estimated as 0.4 mag brighter than this star and 0.8 mag brighter than ζ Sct. The deduced m1 magnitude has been corrected for extinction by using an extinction coefficient of 0.20 mag per air mass. There was also a hint of a short tail towards north. The inner coma remained visible until a solar altitude of -6.7 deg [07h15m UT].) 2006 12 26.65 !S 4.5:TK 20.3L 38 0.5 8 GUZ Krosno (I caught this comet visually on Dec 26.65; unfortunately I found it just at the edge of thin clouds ~3 deg above horizon. I saw it only for several seconds as small, condensed object, comparable to ζ Scuti.) 2006 12 21.74 I [5.0 TK 10.0B 25 GON Puerto de Aralla, León (Not visible. Mountain location, very clear sky; nautical twilight; alt. 3 deg.) 2006 12 17.66 !B [6.0:TK 10.0R 25 ! 1 GRA Fjellhamar (The comet was was not seen despite a clear and transparent sky. Formal observation was obtained at altitude 2.5 deg and solar altitude -11 deg. Stellar limiting magnitude near comet was about 6.5. The principal comparison stars were HD 165360 [mag VT = 7.2 from TK] and HD 164789 [VT = 7.8]. The limiting magnitudes for this and the Dec. 16.66 observations have been corrected for extinction and by using a extinction coefficient of 0.20 mag per air mass.) 2006 12 16.66 !B [5.0:TK 7.0R 20 ! 2 GRA Fjellhamar (No comet was detected near the predicted location, neither visually nor photographically. Formal visual observation was obtained at altitude 2.5 degrees in bright evening twilight [solar altitude -11 degrees]. The comparison star was ζ Oph and the comet must have been at least 1.5 mag fainter than this star when defocused to 2'. The field was subsequently imaged using a Canon EOS 400D digital camera and a 100-mm FL lens.) 2006 12 14.74 I [6.0 TK 10.0B 25 GON Alto del Castro - Aralla, León (Not visible. Mountain location, very clear sky; nautical twilight; alt. 3 deg.) 2006 12 13.74 I [6.5 TK 20.3T 77 GON Alto del Castro - Aralla, León (Not visible. Mountain location, very clear sky; nautical twilight; alt. 3 deg.) 2006 11 16.77 S 9.1 TK 10.0B 25 3 5 GON Alto de Bustellán, Tineo, Asturias (Mountain location, very clear sky; alt. 5 deg.) 2006 11 13.78 S 9.6 TK 20.3T 77 3.0 5 GON Alto del Castro - Aralla, León 2006 11 13.77 S 9.3 TK 10.0B 25 3 5 GON Alto del Castro - Aralla, León (Mountain location, very clear sky; alt. 6 deg; zodiacal light.) 2006 11 9.79 S 9.8 TK 20.3T 77 2 5 GON Alto del Castro - Aralla, León (Mountain location, clear sky; alt. 5 deg; zodiacal light.) 2006 10 13.42 S 11.3 GA 25.4L 71 6 3 SEA Cowra, NSW (Clearest view of comet. Somewhat enhanced thro' Swan Band Filter.) 2006 10 12.81 S 11.7 TK 20.3T 133 2 2 GON Sierra del Aramo, Asturias (Mountain location, clear sky. Altitude: 10 deg.) 2006 10 11.41 S 11.1 GA 10.0B 25 6 SEA Cowra, NSW 2006 10 10.44 S 12.5 AU 28.0T 133 2.5 2 MAT Stockport Observatory, SA (Zodiacal light interference. Comet appears more pronounced than on my previous observation dated Sep 22.) 2006 10 10.42 S 11.4 GA 25.4L 71 4 SEA Cowra, NSW (Also seen in 25x100 binocular telescope at approx. mag. 11.4. Enhanced in BT thro' Swan Band Filter. Very low surface brightness, appearing in field rather like Gegenschein with naked eye!) 2006 10 9.43 S 12.1 GA 25.4L 71 2 1 SEA Cowra, NSW (Comet close to faint star.) 2006 10 9.40 S 12.5:HS 40.0L 144 1.4 2 YOS Kita-karuizawa, Gunma (Very low in the evening. The sky was not very clear and hard to see faint stars. But sometimes the sky became clear. Then I could see very faint stars, and a faint nebulous object, too. Maybe the comet is bright. But probably due to the thin clouds passing through the telescope field, I could not see the comet for a long time. The star chart around this area is very different between the GSC and ASAS-3. The DSS image suggests the GSC is right. So I report my observation using the GSC.) 2006 9 27.44 S[11.9 AU 40.0L 144 !1.1 YOS Kita-karuizawa, Gunma (The comet was hidden by clouds when I observed C/2006 L2 earlier. When the comet appeared again, it was already low. They say it is extremely large and diffuse. The sky was not dark, so it was very hard to see a diffuse object.) 2006 9 24.44 S 13.3 AU 28.0T 133 1.5 1 MAT Blinman, SA 2006 9 22.75 S 12.5:HS 20.3L 63 2 1 GUZ Krosno 2006 9 22.44 S 13.1 AU 28.0T 133 2 1 MAT Blinman, SA 2006 9 17.42 S 13.6 GA 25.4L 114 SEA Cowra, NSW 2006 8 25.48 S 13.9 GA 25.4L 114 0.6 SEA Cowra, NSW (Very marginal, but held for several minutes during a very clear and steady interval.)