6P/ d'Arrest

[martinastro]

Comet number 4 now visible for northern hemisphere observers. This comet is brightening rapidly and was recently caught with a CCD at mag + 13 so it should be at least two magnitudes brigther for visual observers. The comet is currently moving through Aquila and is expected to peak at mag +9.0

Wide field chart...



Ephemeris

http://cfa-www.harvard.edu/iau/Ephemerides/Comets/0006P.html


* C/2007 N3 Lulin might become a naked eye object during Feb.

[Roman White]

I will not hunt for this comet. It is near my magnitude limit and, as I can see on the chart, it "dives" into the southern sky since the beginning of July.

And C/2007 N3 will be my target since late November.

[martinastro]

6P/d'Arrest:
2008 Aug. 19.86 UT: m1=8.3, Dia.=7', DC=3, 20 cm SCT (77x).
[ Starlike nucleus: m2=12.5 (Tycho-2) at 100x, surrounded by an
assymetric condensation of about 0.7'. Astronomical twilight; some
moonlight interference, moon's altitude: 4 deg. Mountain location, very
clear sky ].

( Alto del Trichero - Soto y Amio, alt. 1190 m, Leon, N. Spain )

I spent 1 hour 45 min's looking for it last night with a Moon in the sky and  through murk without success. I will be trying again tonight if it clears. Anyone else?

[Roman White]

What?! 8.3 mag.?!  This outburst makes it as bright as W1 Boattini. Maybe I'll make an effort.
Pity it's much south in Capricornus. I wouldn't have much chances to find a 8-9 mag comet low in the SW horizon (it is not very good at my observing site)

[martinastro]

For the 3rd night in a row I have been hunting for this elusive comet without success...so far. On all the 3 nights the trans was not great and the Moon was visible. Last night had a much improved crystal clear sky although it was murky low in the south. The Moon, 1 day from last 1/4, was low in the NE within Aries. I spent a considerable amount of time hunting for d'Arrest using the 8.5" F/7 reflector and 10x50mm binos. I seen absolutely nothing. I suspect the diffuse nature of this 8th mag comet is the problem. Any haze combined with atmospheric extinction is a big obstacle. The region within Capricornus where the comet resides is visible just above my back garden fence but I think street lights are my biggest threat. I took a few quick images of the region. The first wide shot shows the location of the comet and the  2nd zoomed capture marks the area where the comet is (approx). The Milky Way was quite nice despite the moonlight. Had a quick look at M11, M15, M27 and Jupiter.





Seen Orion last night!

[Roman White]

I didn't even try to search for 6P/d'Arrest. 8-9 magnitude comet + diffuse + low in Capricornus (max 15deg.) + light polluted S horizon + 1/2 Moon is shining = makes very low chances to find it for me.

Instead, I'll make (maybe the last) effort to find comet C/2007W1 again in a few days. Last night the Moon was just in conjunction with the comet and it was also a very hard object.

But at the same time (now) the C/2008 A1  comet is at 7mag. It will come back into northern skies after (approx.) mid-September.