Although not spectacular, Comet Garradd (C/2009 P1) is continuing to put on a fine performance as it heads towards closest approach to the Earth on the 5th March 2012. The comet that was discovered by Gordon Garradd on the 13th August 2009 using the Siding Spring Observatory near Coonabarabran in Australia, has been brightening steadily over the last few months and is expected to peak at around magnitude 6.3 (or maybe slightly brighter) in February 2012.
Despite having an unusually large and bright nucleus, Garrard never approaches very close to either the Earth or the Sun; at closest Earth approach it will still be about 1.27 AU (188 million kilometers or 118 million miles) distant. Despite this, the comet has been a binocular and small telescope object for many months now, with an obvious coma and short but nice tail.
Garradd is now an early morning object, best placed for northern hemisphere observers, and can be found in the constellation of Hercules heading northwards past the head of Draco before reaching its highest point in the sky in Ursa Minor in March.
As it moves across the sky there have already been some nice visual and imaging opportunities; on the 26th August last year the comet passed close by globular cluster M71 and a week later brushed the famous "Coathanger" asterism or Brocchi's Cluster (Collinder 399) in Vulpecula. If you happened to miss these events not to worry as on the 3rd February 2012 Garradd passes only 20 arc minutes to the west of one of the northern skies best globular clusters M92. At this time the comet should also be close to its peak brightness (mag. 6.4) and almost identical in brightness to M92 (mag. 6.3). Both objects should be easily visible in binoculars.
Take some time to visually compare and contrast M92 and Garradd. How close do you think the comet resembles the globular cluster? After all this was the reason why Charles Messier produced his famous catalogue, to avoid confusing deep sky objects such as globular clusters with much sought after comets he was trying to find.
Three weeks later on the 23rd and 24th February, Comet Garradd will pass only a couple of degrees west of magnitude 2.7 yellow giant star eta Draconis.
Comet Garradd Data Table
|Date||RA (J2000)||DEC (J2000)||Estimated Magnitude|
|29/12/2011||17h 30m 15.7s||25d 58m 15s||6.7|
|02/01/2012||17h 30m 02.6s||27d 08m 27s||6.6|
|06/01/2012||17h 29m 39.2s||28d 26m 40s||6.6|
|10/01/2012||17h 29m 02.2s||29d 53m 44s||6.6|
|14/01/2012||17h 28m 07.6s||31d 30m 35s||6.5|
|18/01/2012||17h 26m 50.1s||33d 18m 19s||6.5|
|22/01/2012||17h 25m 03.0s||35d 18m 03s||6.5|
|26/01/2012||17h 22m 37.4s||37d 30m 57s||6.4|
|30/01/2012||17h 19m 21.7s||39d 58m 07s||6.4|
|03/02/2012||17h 15m 00.4s||42d 40m 28s||6.4|
|07/02/2012||17h 09m 12.1s||45d 38m 34s||6.4|
|11/02/2012||17h 01m 27.0s||48d 52m 24s||6.3|
|15/02/2012||16h 51m 01.7s||52d 20m 47s||6.3|
|19/02/2012||16h 36m 52.2s||56d 00m 43s||6.3|
|23/02/2012||16h 17m 24.6s||59d 46m 10s||6.3|
|27/02/2012||15h 50m 25.7s||63d 26m 36s||6.4|
|02/03/2012||15h 13m 08.7s||66d 45m 06s||6.4|
|06/03/2012||14h 23m 21.4s||69d 17m 20s||6.5|
|10/03/2012||13h 22m 34.2s||70d 35m 32s||6.6|
|14/03/2012||12h 18m 47.8s||70d 22m 24s||6.7|
|18/03/2012||11h 22m 22.7s||68d 44m 58s||6.8|
|22/03/2012||10h 38m 26.1s||66d 08m 45s||6.9|
|26/03/2012||10h 06m 19.8s||63d 00m 53s||7.1|
|30/03/2012||09h 43m 20.7s||59d 41m 13s||7.2|