Comet McNaught

To those people in the southern hemisphere, Comic McNaught is now heading your way! I am actually a bit late in the posting, the best time to watch it (which is at its brightest) was yesterday, Jan the 14th. Nevertheless, there is still somewhat of a 4-day-long window of opportunity. So grab it now! Unlike us poor sobs in Malaysia and Singapore, where it is neither the north hemisphere nor the south hemisphere, thus we don't get to see anything.

Comet McNaught was first spotted 2006 August the 7th, by an aussie in NSW (called McNaught, in case you were wondering). Normal comets encircle the sun but leans far away from the earth. These are only of interest to professional astronomers with their professional telescopes and professional machinery and professional education and their professional- *gets shot* Ahem. Whats different about Comet McNaught is that its path goes very near and sometimes into Earth's orbit, and it even goes within Mercury's orbit, and therefore making it very close and very bright. In fact, it may be the brightest comet in 30 years.

I obtained these instructions for the folks in australia who wants to watch this comet:

Visibility from Australia

I'll concentrate my comments on the latitude of Sydney, which will be reasonably accurate for most of the Australian population.

The first possibility to see the comet will be at sunset on Jan 13 when the comet would be a *very* difficult object some 6 degrees north of the azimuth of the just set sun. The comet will set only 7 minutes after the top edge of the sun has set. You would need a very good horizon and beautifully clear skies to see it, but given the possible brightness it is not an impossibility. The tail would lie almost flat along the horizon to the comet's right.

The first real chance will be at sunset on Jan 14 with the comet about 5 degrees from the just set sun, up at 45 degrees to the right (and gas tail continuing away from the sun in that direction). The head of the comet will set about 23 mins after the sun, still in the bright twilight, but as the sky darkens it is probable that the tail will become visible at greater distances from the comet. It is close to sunset on the 14th that the comet will reach its theoretical brightest.

At sunset on Jan 14, the comet will be located only 1.2 deg due right of Mercury which will then be mag. -1, and some 14 deg from Venus which at mag. -4 lies up to the right of the comet. [The magnitude scale is used by astronomers to measure brightness. The Sun is mag. -26, the full moon mag. -12 and the faintest stars you see on a dark night are about mag. +6.]

The best geometry occurs on Jan 15, with the comet starting to move away from the sun (now 7 degrees) and almost directly above the position of the sun at sunset. The head will set about 39 mins after the sun, although the azimuth at which it sets will be 5.0 degrees to the left of the sunset point. It is quite reasonable to expect the tail to remain visible up to an hour after sunset, so it may be seen in a dark sky.

On Jan 15 the comet is already 3 degrees from Mercury, up to the left.

By Jan 16, the effect of forward scattering will have dropped back to about zero and the comet will already be heading away from the Sun and Earth; back to the obscurity of the Oort cloud. Although now clearly fading, it will be moving higher into the southern sky away from the sun. At sunset on the 16th, the comet will be about 10 degrees from the sun and just left of directly above the Sun at sunset. It will set 54 mins after the sun, 9 degrees to the left of the sunset point.

From Jan 17 onwards, the comet, although fainter, should be well visible in the darker skies. It then moves into the SW sky at roughly a 45 deg angle up to the left of the sunset point. The angular distance of the comet from sun at the time of sunset from Sydney then increases on a daily basis:

Jan 17  12deg
18  15deg
19  17deg

after which date the head of the comet will set when the sun has already passed more than 18 degrees below the horizon (astronomical darkness).

Theres also this nice picture to help those who are picture orientated:


Hope you guys can spot it! For those who wants to see pictures of it, here are some pretty good ones taken when it streaked past the northern hemisphere. As an addendum: From Jan 12 till Jan 15, the comet streaked past the field of view of the Solar and Heliospheric Observatory ("SOHO"), so we can expect to see some pretty spectacular photos soon.

Good luck!