Comet Encke (2P/Encke) the periodic comet with the shortest orbital period of all know comets (3.3 years) is now visible with binoculars and small telescopes from the northern hemisphere and tropics. It can be seen low down towards the east in the early morning sky. Unfortunately, from the southern hemisphere it's not observable.
Recent observations at the beginning of the month put Encke at magnitude +7.7 with a bright core of about 2 arc minutes in diameter surrounded by a fainter coma some 10 arc minutes across. The comet will continue to brighten, although only slightly, until it peaks at about magnitude +7.1 just before perihelion (Nov. 21st). It remains visible to observers until about the 18th, before been finally lost to the bright dawn twilight sky.
At perihelion, Encke approaches to within 0.33625 AU (approx. 50.30 million kilometres or 31.26 million miles) of the Sun.
The finder charts below show the positions of Encke from November 3rd until November 18th as it moves through Virgo. On November 16th/17th, Mercury (mag. -0.5) will be positioned just a few degrees from Encke.
Comet Encke Finder Chart from November 3 to November 18, 2013 - pdf format
Comet 2P/Encke Data Table (at epoch August 21, 2012)
| Name | 2P/Encke |
|---|---|
| Type | Comet |
| Classification | Encke-type comet (NEO) |
| Discoverer | Pierre Méchain, Johann Franz Encke first recognised the periodicity |
| Discovery date | 1786 (orbit computed by Encke in 1819) |
| Aphelion (AU) | 4.09236 |
| Perihelion (AU) | 0.33625 |
| Semi-major axis (AU) | 2.21430 |
| Eccentricity | 0.84815 |
| Orbital period (years) | 3.29513 |
| Inclination (degrees) | 11.7773 |
| Longitude of ascending node (degrees) | 334.572 |
| Last perihelion | August 6th, 2010 |
| Next perihelion | November 21st, 2013 |
| Notes | Comet Encke has the shortest orbital period of any known comet |
Comet Encke (2P/Encke) Data Table
| Date | Right Ascension | Declination | Estimated Magnitude | Distance from Earth (AU) | Constellation |
|---|---|---|---|---|---|
| 01 Nov 2013 | 12h 35m 04s | 09d 20m 19s | 7.7 | 0.600 | Virgo |
| 02 Nov 2013 | 12h 41m 39s | 07d 49m 14s | 7.7 | 0.617 | Virgo |
| 03 Nov 2013 | 12h 48m 00s | 06d 20m 31s | 7.7 | 0.634 | Virgo |
| 04 Nov 2013 | 12h 54m 10s | 04d 54m 09s | 7.6 | 0.652 | Virgo |
| 05 Nov 2013 | 13h 00m 08s | 03d 30m 05s | 7.6 | 0.671 | Virgo |
| 06 Nov 2013 | 13h 05m 58s | 02d 08m 13s | 7.6 | 0.692 | Virgo |
| 07 Nov 2013 | 13h 11m 40s | 00d 48m 28s | 7.5 | 0.712 | Virgo |
| 08 Nov 2013 | 13h 17m 16s | -00d 29m 19s | 7.5 | 0.734 | Virgo |
| 09 Nov 2013 | 13h 22m 48s | -01d 45m 14s | 7.4 | 0.757 | Virgo |
| 10 Nov 2013 | 13h 28m 17s | -02d 59m 25s | 7.4 | 0.781 | Virgo |
| 11 Nov 2013 | 13h 33m 45s | -04d 12m 02s | 7.3 | 0.805 | Virgo |
| 12 Nov 2013 | 13h 39m 14s | -05d 23m 11s | 7.3 | 0.830 | Virgo |
| 13 Nov 2013 | 13h 44m 44s | -06d 32m 59s | 7.2 | 0.856 | Virgo |
| 14 Nov 2013 | 13h 50m 19s | -07d 41m 34s | 7.2 | 0.883 | Virgo |
| 15 Nov 2013 | 13h 55m 59s | -08d 48m 59s | 7.2 | 0.911 | Virgo |
| 16 Nov 2013 | 14h 01m 46s | -09d 55m 18s | 7.1 | 0.939 | Virgo |
| 17 Nov 2013 | 14h 07m 42s | -11d 00m 30s | 7.1 | 0.968 | Virgo |
| 18 Nov 2013 | 14h 13m 47s | -12d 04m 33s | 7.1 | 0.997 | Virgo |
| 19 Nov 2013 | 14h 20m 02s | -13d 07m 23s | 7.1 | 1.026 | Virgo |
| 20 Nov 2013 | 14h 26m 29s | -14d 08m 51s | 7.1 | 1.056 | Libra |
| 21 Nov 2013 | 14h 33m 06s | -15d 08m 47s | 7.2 | 1.085 | Libra |
| 22 Nov 2013 | 14h 39m 53s | -16d 06m 58s | 7.2 | 1.114 | Libra |
| 23 Nov 2013 | 14h 46m 50s | -17d 03m 12s | 7.3 | 1.143 | Libra |
| 24 Nov 2013 | 14h 53m 54s | -17d 57m 15s | 7.4 | 1.172 | Libra |
| 25 Nov 2013 | 15h 01m 05s | -18d 48m 57s | 7.5 | 1.199 | Libra |
| 26 Nov 2013 | 15h 08m 20s | -19d 38m 08s | 7.6 | 1.226 | Libra |
| 27 Nov 2013 | 15h 15m 37s | -20d 24m 41s | 7.7 | 1.253 | Libra |
| 28 Nov 2013 | 15h 22m 56s | -21d 08m 34s | 7.9 | 1.278 | Libra |
| 29 Nov 2013 | 15h 30m 14s | -21d 49m 44s | 8.0 | 1.303 | Libra |
| 30 Nov 2013 | 15h 37m 31s | -22d 28m 13s | 8.2 | 1.327 | Libra |
| 01 Dec 2013 | 15h 44m 44s | -23d 04m 04s | 8.3 | 1.351 | Libra |
| 02 Dec 2013 | 15h 51m 53s | -23d 37m 22s | 8.5 | 1.374 | Scorpius |
| 03 Dec 2013 | 15h 58m 58s | -24d 08m 11s | 8.6 | 1.396 | Scorpius |
| 04 Dec 2013 | 16h 05m 57s | -24d 36m 37s | 8.7 | 1.418 | Scorpius |
| 05 Dec 2013 | 16h 12m 50s | -25d 02m 48s | 8.9 | 1.440 | Scorpius |
| 06 Dec 2013 | 16h 19m 37s | -25d 26m 50s | 9.0 | 1.461 | Scorpius |
| 07 Dec 2013 | 16h 26m 17s | -25d 48m 49s | 9.2 | 1.482 | Scorpius |
| 08 Dec 2013 | 16h 32m 51s | -26d 08m 53s | 9.3 | 1.502 | Scorpius |
| 09 Dec 2013 | 16h 39m 18s | -26d 27m 07s | 9.4 | 1.523 | Scorpius |
| 10 Dec 2013 | 16h 45m 38s | -26d 43m 37s | 9.6 | 1.543 | Scorpius |
| 11 Dec 2013 | 16h 51m 51s | -26d 58m 31s | 9.7 | 1.562 | Scorpius |
| 12 Dec 2013 | 16h 57m 58s | -27d 11m 53s | 9.9 | 1.582 | Ophiuchus |
| 13 Dec 2013 | 17h 03m 57s | -27d 23m 49s | 10.2 | 1.601 | Ophiuchus |
| 14 Dec 2013 | 17h 09m 50s | -27d 34m 24s | 10.4 | 1.620 | Ophiuchus |
| 15 Dec 2013 | 17h 15m 36s | -27d 43m 43s | 10.6 | 1.639 | Ophiuchus |
| 16 Dec 2013 | 17h 21m 15s | -27d 51m 51s | 10.8 | 1.658 | Ophiuchus |
| 17 Dec 2013 | 17h 26m 48s | -27d 58m 51s | 11.0 | 1.677 | Ophiuchus |
| 18 Dec 2013 | 17h 32m 14s | -28d 04m 49s | 11.2 | 1.695 | Ophiuchus |
| 19 Dec 2013 | 17h 37m 34s | -28d 09m 47s | 11.4 | 1.714 | Ophiuchus |
| 20 Dec 2013 | 17h 42m 48s | -28d 13m 50s | 11.6 | 1.732 | Ophiuchus |
| 21 Dec 2013 | 17h 47m 56s | -28d 17m 00s | 11.8 | 1.750 | Sagittarius |
| 22 Dec 2013 | 17h 52m 58s | -28d 19m 22s | 12.0 | 1.768 | Sagittarius |
| 23 Dec 2013 | 17h 57m 54s | -28d 20m 58s | 12.1 | 1.786 | Sagittarius |
| 24 Dec 2013 | 18h 02m 44s | -28d 21m 51s | 12.3 | 1.804 | Sagittarius |
| 25 Dec 2013 | 18h 07m 29s | -28d 22m 03s | 12.5 | 1.822 | Sagittarius |
| 26 Dec 2013 | 18h 12m 08s | -28d 21m 38s | 12.6 | 1.839 | Sagittarius |
| 27 Dec 2013 | 18h 16m 43s | -28d 20m 37s | 12.8 | 1.857 | Sagittarius |
| 28 Dec 2013 | 18h 21m 11s | -28d 19m 02s | 12.9 | 1.874 | Sagittarius |
| 29 Dec 2013 | 18h 25m 35s | -28d 16m 57s | 13.1 | 1.891 | Sagittarius |
| 30 Dec 2013 | 18h 29m 54s | -28d 14m 22s | 13.2 | 1.908 | Sagittarius |
| 31 Dec 2013 | 18h 34m 09s | -28d 11m 20s | 13.4 | 1.925 | Sagittarius |
See also
Comet Encke (2P/Encke) now rapidly brightening in the morning sky