Comet ISON, the predicted super comet of 2013, has now brightened to 10th magnitude and within the range of medium aperture telescopes. When discovered at the end of last year, the hype surrounding this possible "comet of the century" went into overdrive. It was predicted to reach an incredible magnitude -16, visible in daylight and be brighter than the full Moon, when close to perihelion in late November 2013.
At perihelion ISON will be only 0.01249 AU (1.87 million kilometres or 1.16 million miles) from the Sun. At such a small distance, there's a real possibility it might not even survive the hostile environment, disintegrating before reaching the other side.
What was also over looked in the popular press last year was that peak brightness occurs for just a few hours during daytime. And of course an object at magnitude -16, right next to our star, appears nowhere near as bright as might be expected. But anyway, it's still an exciting prospect and a potentially great spectacle over the next couple of months.
Recent estimates now suggest that the ISON will peak at about magnitude -7 or -8. On October 11th, the comet stood at magnitude +10.6 with an elongated coma, visible in 250mm (10-inch) or 200mm (8-inch) telescopes in the morning skies just before sunrise. Visually detecting a tail was more difficult. However, the comet and tail could be imaged with much smaller scopes.
ISON is expected to reach naked eye brightness about the middle of November and remain so until the end of December. During this time the best location to be is the Northern Hemisphere. It will be observable in the early morning sky towards the east throughout the brightening period. From the Southern Hemisphere, the condition is not so great with the comet remaining low down during this time.
The finder chart below shows the path of ISON from October 9th to October 29th as it moves through Leo. Also in Leo during this time in Mars and ISON will move eastwards towards Mars before overtaking it. On October 15th, ISON (mag. +10.2) will be about a degree north of Mars (mag. +1.5) and two degrees north of Regulus (α Leo - mag. +1.4). The latter two are about the same brightness and easily visible to the naked eye but the comet is much fainter (3000x) and probably requires at least a 100mm (4-inch) telescope to be seen; preferably a larger scope. Mars and Regulus do act as good pointers to locate ISON.
Comet ISON Finder Chart from October 9 to October 29, 2013 - pdf format
On October 25th, ISON is predicted to be at magnitude +9.2 and located 1.5 degrees south of three 10th magnitude Messier galaxies, M95, M96 and M105. The comet is a magnitude brighter than the galaxies but may appear similar in appearance, size and shape.
ISON remains in Leo for the remainder of October before moving into Virgo next month when the real fun begins!!
Comet ISON (C/2012 S1) Data (at epoch February 28. 2013)
Name | C/2012 S1 (ISON) |
---|---|
Type | Comet |
Classification | Hyperbolic Comet |
Discoverer | Vitali Nevski and Artyom Novichonok using the ISON group of telescopes |
Discovery date | September 21, 2012 |
Aphelion (AU) | unknown |
Perihelion (AU) | 0.01249 |
Eccentricity | 1.000005 |
Orbital period (years) | unknown |
Inclination (degrees) | 61.981 |
Longitude of ascending node (degrees) | 295.716 |
Perihelion | November 28th, 2013 |
Notes | Sungrazing comet |
Comet ISON (C/2012 S1) Data Table
Date | Right Ascension | Declination | Estimated Magnitude | Distance from Earth (AU) | Constellation |
---|---|---|---|---|---|
01 Oct 2013 | 09h 34m 35s | 17d 37m 29s | 11.3 | 2.151 | Leo |
02 Oct 2013 | 09h 36m 43s | 17d 25m 01s | 11.2 | 2.121 | Leo |
03 Oct 2013 | 09h 38m 54s | 17d 12m 12s | 11.2 | 2.092 | Leo |
04 Oct 2013 | 09h 41m 07s | 16d 59m 02s | 11.1 | 2.062 | Leo |
05 Oct 2013 | 09h 43m 23s | 16d 45m 30s | 11.0 | 2.032 | Leo |
06 Oct 2013 | 09h 45m 41s | 16d 31m 34s | 10.9 | 2.003 | Leo |
07 Oct 2013 | 09h 48m 02s | 16d 17m 14s | 10.9 | 1.973 | Leo |
08 Oct 2013 | 09h 50m 26s | 16d 02m 27s | 10.8 | 1.943 | Leo |
09 Oct 2013 | 09h 52m 52s | 15d 47m 14s | 10.7 | 1.913 | Leo |
10 Oct 2013 | 09h 55m 22s | 15d 31m 31s | 10.6 | 1.883 | Leo |
11 Oct 2013 | 09h 57m 55s | 15d 15m 18s | 10.6 | 1.853 | Leo |
12 Oct 2013 | 10h 00m 32s | 14d 58m 33s | 10.5 | 1.823 | Leo |
13 Oct 2013 | 10h 03m 12s | 14d 41m 14s | 10.4 | 1.793 | Leo |
14 Oct 2013 | 10h 05m 56s | 14d 23m 20s | 10.3 | 1.762 | Leo |
15 Oct 2013 | 10h 08m 45s | 14d 04m 46s | 10.2 | 1.732 | Leo |
16 Oct 2013 | 10h 11m 38s | 13d 45m 33s | 10.1 | 1.702 | Leo |
17 Oct 2013 | 10h 14m 35s | 13d 25m 37s | 10.0 | 1.672 | Leo |
18 Oct 2013 | 10h 17m 37s | 13d 04m 55s | 9.9 | 1.642 | Leo |
19 Oct 2013 | 10h 20m 45s | 12d 43m 25s | 9.8 | 1.611 | Leo |
20 Oct 2013 | 10h 23m 58s | 12d 21m 04s | 9.7 | 1.581 | Leo |
21 Oct 2013 | 10h 27m 17s | 11d 57m 48s | 9.6 | 1.551 | Leo |
22 Oct 2013 | 10h 30m 42s | 11d 33m 34s | 9.5 | 1.521 | Leo |
23 Oct 2013 | 10h 34m 14s | 11d 08m 18s | 9.4 | 1.491 | Leo |
24 Oct 2013 | 10h 37m 53s | 10d 41m 57s | 9.3 | 1.462 | Leo |
25 Oct 2013 | 10h 41m 39s | 10d 14m 25s | 9.2 | 1.432 | Leo |
26 Oct 2013 | 10h 45m 34s | 09d 45m 38s | 9.1 | 1.402 | Leo |
27 Oct 2013 | 10h 49m 37s | 09d 15m 31s | 9.0 | 1.373 | Leo |
28 Oct 2013 | 10h 53m 49s | 08d 43m 59s | 8.9 | 1.344 | Leo |
29 Oct 2013 | 10h 58m 12s | 08d 10m 56s | 8.7 | 1.315 | Leo |
30 Oct 2013 | 11h 02m 44s | 07d 36m 16s | 8.6 | 1.286 | Leo |
31 Oct 2013 | 11h 07m 28s | 06d 59m 53s | 8.5 | 1.258 | Leo |
01 Nov 2013 | 11h 12m 24s | 06d 21m 39s | 8.3 | 1.230 | Leo |
02 Nov 2013 | 11h 17m 33s | 05d 41m 28s | 8.2 | 1.202 | Leo |
03 Nov 2013 | 11h 22m 56s | 04d 59m 13s | 8.1 | 1.175 | Leo |
04 Nov 2013 | 11h 28m 33s | 04d 14m 46s | 7.9 | 1.148 | Leo |
05 Nov 2013 | 11h 34m 27s | 03d 27m 58s | 7.8 | 1.122 | Leo |
06 Nov 2013 | 11h 40m 37s | 02d 38m 44s | 7.6 | 1.096 | Virgo |
07 Nov 2013 | 11h 47m 05s | 01d 46m 54s | 7.5 | 1.072 | Virgo |
08 Nov 2013 | 11h 53m 53s | 00d 52m 22s | 7.3 | 1.047 | Virgo |
09 Nov 2013 | 12h 01m 02s | -00d 04m 59s | 7.1 | 1.024 | Virgo |
10 Nov 2013 | 12h 08m 33s | -01d 05m 14s | 7.0 | 1.002 | Virgo |
11 Nov 2013 | 12h 16m 28s | -02d 08m 26s | 6.8 | 0.980 | Virgo |
12 Nov 2013 | 12h 24m 48s | -03d 14m 38s | 6.6 | 0.960 | Virgo |
13 Nov 2013 | 12h 33m 35s | -04d 23m 48s | 6.4 | 0.941 | Virgo |
14 Nov 2013 | 12h 42m 50s | -05d 35m 52s | 6.2 | 0.924 | Virgo |
15 Nov 2013 | 12h 52m 34s | -06d 50m 42s | 6.0 | 0.908 | Virgo |
16 Nov 2013 | 13h 02m 50s | -08d 08m 02s | 5.8 | 0.894 | Virgo |
17 Nov 2013 | 13h 13m 38s | -09d 27m 35s | 5.6 | 0.881 | Virgo |
18 Nov 2013 | 13h 25m 00s | -10d 48m 53s | 5.4 | 0.871 | Virgo |
19 Nov 2013 | 13h 36m 57s | -12d 11m 24s | 5.1 | 0.864 | Virgo |
20 Nov 2013 | 13h 49m 29s | -13d 34m 26s | 4.8 | 0.858 | Virgo |
21 Nov 2013 | 14h 02m 36s | -14d 57m 12s | 4.6 | 0.856 | Virgo |
22 Nov 2013 | 14h 16m 21s | -16d 18m 46s | 4.2 | 0.857 | Virgo |
23 Nov 2013 | 14h 30m 43s | -17d 38m 06s | 3.9 | 0.861 | Libra |
24 Nov 2013 | 14h 45m 44s | -18d 54m 03s | 3.4 | 0.869 | Libra |
25 Nov 2013 | 15h 01m 29s | -20d 05m 16s | 2.9 | 0.882 | Libra |
26 Nov 2013 | 15h 18m 06s | -21d 10m 03s | 2.2 | 0.900 | Libra |
27 Nov 2013 | 15h 36m 00s | -22d 05m 35s | 1.1 | 0.924 | Libra |
28 Nov 2013 | 15h 56m 31s | -22d 43m 30s | -0.9 | 0.960 | Scorpius |
29 Nov 2013 | 16h 23m 17s | -19d 52m 17s | -4.1 | 0.976 | Scorpius |
30 Nov 2013 | 16h 21m 22s | -16d 20m 14s | 0.2 | 0.912 | Scorpius |
01 Dec 2013 | 16h 19m 11s | -13d 58m 52s | 1.6 | 0.868 | Scorpius |
02 Dec 2013 | 16h 17m 23s | -11d 55m 49s | 2.4 | 0.831 | Scorpius |
03 Dec 2013 | 16h 15m 54s | -10d 00m 41s | 2.9 | 0.798 | Scorpius |
04 Dec 2013 | 16h 14m 39s | -08d 09m 09s | 3.4 | 0.768 | Ophiuchus |
05 Dec 2013 | 16h 13m 36s | -06d 18m 51s | 3.7 | 0.740 | Ophiuchus |
06 Dec 2013 | 16h 12m 44s | -04d 28m 14s | 4.0 | 0.714 | Ophiuchus |
07 Dec 2013 | 16h 12m 02s | -02d 36m 10s | 4.2 | 0.690 | Serpens Caput |
08 Dec 2013 | 16h 11m 27s | 00d 41m 45s | 4.4 | 0.667 | Serpens Caput |
09 Dec 2013 | 16h 11m 00s | 01d 15m 45s | 4.6 | 0.644 | Serpens Caput |
10 Dec 2013 | 16h 10m 41s | 03d 17m 02s | 4.7 | 0.623 | Serpens Caput |
11 Dec 2013 | 16h 10m 27s | 05d 22m 41s | 4.9 | 0.603 | Serpens Caput |
12 Dec 2013 | 16h 10m 20s | 07d 33m 18s | 5.0 | 0.584 | Serpens Caput |
13 Dec 2013 | 16h 10m 19s | 09d 49m 24s | 5.1 | 0.566 | Serpens Caput |
14 Dec 2013 | 16h 10m 24s | 12d 11m 29s | 5.2 | 0.549 | Serpens Caput |
15 Dec 2013 | 16h 10m 34s | 14d 39m 59s | 5.3 | 0.532 | Serpens Caput |
16 Dec 2013 | 16h 10m 51s | 17d 15m 19s | 5.3 | 0.517 | Hercules |
17 Dec 2013 | 16h 11m 13s | 19d 57m 46s | 5.4 | 0.503 | Hercules |
18 Dec 2013 | 16h 11m 41s | 22d 47m 33s | 5.5 | 0.489 | Hercules |
19 Dec 2013 | 16h 12m 16s | 25d 44m 46s | 5.5 | 0.477 | Corona Borealis |
20 Dec 2013 | 16h 12m 58s | 28d 49m 21s | 5.6 | 0.466 | Corona Borealis |
21 Dec 2013 | 16h 13m 47s | 32d 01m 04s | 5.7 | 0.457 | Corona Borealis |
22 Dec 2013 | 16h 14m 44s | 35d 19m 30s | 5.7 | 0.448 | Corona Borealis |
23 Dec 2013 | 16h 15m 51s | 38d 43m 59s | 5.8 | 0.442 | Corona Borealis |
24 Dec 2013 | 16h 17m 07s | 42d 13m 39s | 5.9 | 0.436 | Hercules |
25 Dec 2013 | 16h 18m 36s | 45d 47m 25s | 5.9 | 0.432 | Hercules |
26 Dec 2013 | 16h 20m 19s | 49d 24m 02s | 6.0 | 0.430 | Hercules |
27 Dec 2013 | 16h 22m 19s | 53d 02m 04s | 6.1 | 0.429 | Draco |
28 Dec 2013 | 16h 24m 41s | 56d 40m 01s | 6.2 | 0.430 | Draco |
29 Dec 2013 | 16h 27m 31s | 60d 16m 21s | 6.3 | 0.433 | Draco |
30 Dec 2013 | 16h 30m 57s | 63d 49m 32s | 6.4 | 0.437 | Draco |
31 Dec 2013 | 16h 35m 13s | 67d 18m 09s | 6.5 | 0.442 | Draco |