C/2011 L4 PANSTARRS

The Great Binocular Comet of March 2013
Closest to Earth on 6 March 2013 at 1.09AU
Closest to Sun on 10 March 2013 at 0.30AU
Maximum magnitude 1 in mid March 2013

Left: Personal lightcurve vs MPC prediction(red) updated Feb 7. H=5.6, n=2.6
 Predicted peak magnitude of 2.0 in March 2013. (POST NOTE comet made slightly better than this)

Right:  finder chart 35S, early March evening sky.


PLEASE NOTE Comet will move too far north from March 10th and will then only be visible from the Northern Hemisphere.


2013 March 5.42UT.
Comet in deep twilight and probably my last observation.  Canon 60Da


2013 March 4.42UT
Taken through Canon 300D and 300mm lens. Note the difference between this old camera and my new 60Da shots.
Less sensitive but can still do a reasonable job.
Visual magnitude 2.0. Dust tail length 2.5 degrees.


2013 March 3.42UT
L
eft: stack 2.5 mintes at 300mm. Canon 60Da
Right: single 1.5 minute exposure and 100mm zoom lens.
The dust tail length is 2.5 degrees.

2013 March 1.4UT
Left: Canon 60Da and 300mm zoom lens cropped.
Right: A wide field shot at 200mm and a 3 minute exposure.
The 3 tails of comet PANSTARRS
At top is the faint narrow type I gas or ion tail - 3 degrees long
below this is the broad bright Type II dust tail - 2.5 degrees long
and running left at bottom is the Type III dust "trail" - 1 degree long. (made of heavy dust particles)
 


2013 Feb 28.41 UT
Left: Canon 60Da, 3x1 minute stack. 300mm lens, cropped. Magnitude 2.6
Power lines interfere with view.
In 25x100mm binoculars, the dust tail measured 1.5 degrees in PA165, with the much fainter and shorter type 3 dust trail in PA 205.
The ion tail was not visible visually but is at least 2 degrees long in PA155
Right: 10x5 second exposures. starlight express MX7c CCD imager, Celestron C11 telescope.
Digitally processed to show detail in the head. Note the dark lane running up the tail.


2013 Feb 23.41 UT
Canon 60Da, 30 seconds. 100mm lens, cropped. Magnitude 3.8.


2013 Feb 17.75 UT
Canon 60Da, 3x2 minute stack. 300mm zoom lens, cropped.


2013 Feb 15.75 UT
Canon 60Da, 5x2 minute stack. 300mm zoom lens, cropped. Magnitude 5.0.
Dust tail 50' and ion tail nearly 2 degrees long. Magnitude 6 star is just above comet head.



2013 Feb 8.75 UT
Canon 60Da, 5x2 minute stack. 300mm zoom lens, cropped. Magnitude 5.9.
The ion tail is nearly 1 degree in PA 210 whilst the leading edge of the dust tail is 30' in PA 250.
Notice the broad dust fan.


2013 Feb 2.73 UT
Canon 60Da, 5x2 minute stack. 300mm zoom lens, cropped. Magnitude 6.7. Bright stars to the left are Beta 1,2 Sgr.


2013 Jan 27.7UT
Canon 60Da, 5x20sec stack, C11 telescope at F6. Full moon interference.

 
Left: 2013 Jan 16.73 UT
Canon 60Da, 5x2 minute stack. 300mm zoom lens, cropped. Globular cluster NGC 6541 is on the right.
Right: 2013 Jan 19.73UT
Canon 60Da, 5x2 minute stack. 300mm zoom lens

Hidden from view by the Sun since October 2012, comet PANSTARRS reappeared as a magnitude 8.5 object in early January,
situated in the tail of the Scorpion before dawn. By the end of the month, it brightened to magnitude 7.0.
Moon free period occured between January 11 to 24.
Observations during January seem to indicate that its rate of brightening slowed down. This is what is expected for a dynamically new comet.
It may only peak at magnitude 2 in March, still bright by cometary standards, but situated in twilight.
A clear south eastern and south western horizon is required to spot the comet.
On February 1, you will find the magnitude 6 comet situated in Telescopium, low in the southeastern sky before dawn,
near the bright pair Beta 1,2 Sgr. Moonlight interferes with the view until Feb 9.
On the morning of Feb 11, the now magnitude 5.0 comet is 2 degrees northwest of Alpha Indii, still maintaining low elevation.
You may also check out magnitude 9 comet C/2011 F1 LINEAR in the near vicinity.
The comet enters Grus on Feb 18, and has brightened to magnitude 4.0.
Observing circumstances now start to get difficult, with the comets elongation decreasing to 23 degrees by the end of
February, but this is compensated somewhat by its rapid brightening.
On Feb 21, the mag 4.0 comet is adjacent to mag 4.6 star Lambda Gruis and direct comparison with this star will tell you how the comet is faring.
The comet is in solar conjuntion on Feb 23, and now swings into the evening sky, low in twilight.
On Feb 25, the now magnitude 3.0 comet is a degree south of mag 4.5 star Gamma PsA.
By the start of March, moonlight no longer interferes, and C/2011 L4 and C/2012 F6 can be seen simultaneously with the
unaided eye from a dark southern hemisphere site. L4 however will be situated very low in twilight.


2012 Oct 2.40UT
4x2minute combined exposure. Canon 300D at 800asa, 250mm zoom lens.
Appears as a small white object arrowed. Approximate magnitude 11.8.
No hint of coma development (gas which usually appears blue/green). The white colour indicates a dust rich object.


2012 Sep 9.40UT.
20x10 second exposures. C11 SCT and Starlight Express MX7c CCD imager.
Right - digital development filter to reveal tail curvature in the head of the comet.