Follow comet 103P Hartley 2 in September

The first two weeks of September 2010 should be a good time to begin a search for comet 103P Hartley. By that time the should be bright enough to see in a modest size telescope. Depending of course that it follows the redicted pattern of increased brightness.

Already I have read online that this comet will be visible to the unaided eye when at maximum  brightness of 5th magnitude. Let me point out that this depend upon the extend of the size of the coma. A 5th magnitude star is can be difficult enough to see for newbies to astronomy, a diffuse object of 5th magnitude will be more difficult.

To brush up on comet observing you can review information on the topic in November Observing post (2009) in this  Observing Notes blog.

I do expect this comet get some press in newspapers and featured in popular online news outlets for two reasons. It will make a close approach to Earth, some 0.12 A.U., Astronomical Units, roughly 11 million miles (October 20, 2010). The other reason, the  spacecraft EPOXI, you know it as the Deep Impact http://deepimpact.umd.edu/ is on it’s way to a encounter this comet in November 2010. That alone will insure some press coverage.

Here is a list produced from the software Guide version 8. The positions are for zero hours Universal Time, U.T., from orbital elements at this time. the column labeled “r” is distance from the Sun in A.U. and “delta” from the Earth in A.U.
P/Hartley (103P)

UT  Date          Time             RA            declination     r        delta     mag
——-                —-                 —               ———–       –        —–           —
6 Aug 2010  0:00:00  22h31m12.13s  +25 49′ 39.2″  1.5250  0.6452 11.2
9 Aug 2010  0:00:00  22h33m05.26s  +27 06′ 52.9″  1.4992  0.6122 11.0
12 Aug 2010  0:00:00  22h34m58.18s  +28 25′ 36.8″  1.4736  0.5803 10.7
15 Aug 2010  0:00:00  22h36m52.77s  +29 45′ 51.9″  1.4483  0.5495 10.4
18 Aug 2010  0:00:00  22h38m51.36s  +31 07′ 41.5″  1.4233  0.5197 10.1
21 Aug 2010  0:00:00  22h40m56.67s  +32 31′ 10.7″  1.3987  0.4910  9.9
24 Aug 2010  0:00:00  22h43m11.94s  +33 56′ 25.2″  1.3744  0.4632  9.6
27 Aug 2010  0:00:00  22h45m41.09s  +35 23′ 32.0″  1.3506  0.4363  9.3
30 Aug 2010  0:00:00  22h48m28.97s  +36 52′ 38.9″  1.3273  0.4103  9.0
2 Sep 2010  0:00:00  22h51m41.73s  +38 23′ 55.5″  1.3044  0.3852  8.7
5 Sep 2010  0:00:00  22h55m27.25s  +39 57′ 32.1″  1.2822  0.3610  8.4
8 Sep 2010  0:00:00  22h59m55.89s  +41 33′ 41.3″  1.2606  0.3375  8.2
11 Sep 2010  0:00:00  23h05m21.42s  +43 12′ 38.3″  1.2398  0.3148  7.9
14 Sep 2010  0:00:00  23h12m01.93s  +44 54′ 40.7″  1.2197  0.2929  7.6
17 Sep 2010  0:00:00  23h20m21.04s  +46 40′ 01.0″  1.2004  0.2718  7.3
20 Sep 2010  0:00:00  23h30m49.90s  +48 28′ 32.2″  1.1821  0.2514  7.0
23 Sep 2010  0:00:00  23h44m10.21s  +50 19′ 26.0″  1.1647  0.2318  6.7
26 Sep 2010  0:00:00  00h01m17.60s  +52 10′ 32.8″  1.1485  0.2131  6.3
29 Sep 2010  0:00:00  00h23m24.21s  +53 57′ 12.3″  1.1333  0.1954  6.0
2 Oct 2010  0:00:00  00h51m55.59s  +55 30′ 22.4″  1.1194  0.1788  5.7
5 Oct 2010  0:00:00  01h28m10.66s  +56 34′ 11.0″  1.1067  0.1635  5.4
8 Oct 2010  0:00:00  02h12m28.45s  +56 44′ 12.9″  1.0954  0.1499  5.2
11 Oct 2010  0:00:00  03h02m48.53s  +55 30′ 14.7″  1.0855  0.1384  4.9
14 Oct 2010  0:00:00  03h54m27.01s  +52 27′ 17.0″  1.0771  0.1295  4.7
17 Oct 2010  0:00:00  04h41m58.66s  +47 30′ 41.3″  1.0702  0.1235  4.5
20 Oct 2010  0:00:00  05h22m04.41s  +41 02′ 30.3″  1.0649  0.1209  4.5
23 Oct 2010  0:00:00  05h54m09.45s  +33 43′ 19.6″  1.0612  0.1218  4.4
26 Oct 2010  0:00:00  06h19m13.45s  +26 16′ 38.6″  1.0591  0.1260  4.5
29 Oct 2010  0:00:00  06h38m40.99s  +19 15′ 49.7″  1.0587  0.1330  4.6
1 Nov 2010  0:00:00  06h53m48.57s  +12 59′ 19.2″  1.0600  0.1425  4.8
4 Nov 2010  0:00:00  07h05m36.19s  +07 32′ 58.3″  1.0628  0.1537  5.0
7 Nov 2010  0:00:00  07h14m48.68s  +02 55′ 00.1″  1.0673  0.1663  5.2

A plot of the comet’s path from TheSky6 follows.

This entry was posted in Observing Notes. Bookmark the permalink.

Comments are closed.