2011 08 27 – C/2009 P1 & M71

2011 08 27, 0130UT-0300UT – C/2009 P1 (Garradd) near M71 (NGC 6838)
PCW Memorial Observatory, Ohio, USA, Erika Rix

Discovered 2 yrs ago by Gordon Garradd in Australia, C/2009 P1 was at 17th magnitude and predicted to brighten to a magnitude of 6 as it approaches the Sun. It reaches perihelion on December 23rd at 1.55 au. Sky and Telescope provided a printable finder chart for Comet Garradd from September through early February 2012 for easy tracking. Sky and Telescope Garradd Finder

Comet Garradd was near globular cluster M71
Constellation – Sagitta
Radius: 9999 meters
Apparent magnitude: 8.17
Orbit size: 1.5506 au
Distance from Earth: 1.3956 au
Distance from Sun: 2.2125 au
RA: 19h 53.167m Dec: 19:0.658

Sketch details: Garradd is to the left in the sketch, M71 to the right. Sketch created on card stock, 0.5mm mechanical pencil, #2 pencil, blending stump, ultra fine black permanent marker.

My sketch is unfinished and unfortunately, I wasn’t able to get to the report sooner and discovered I had omitted details about the observation such as which eyepiece I used and sky conditions. I believe I used a 13mm Ethos looking at the FOV and the air was saturated from humidity. Visually, the coma was bright with a concentrated nucleus and I was unable to see a tail. Looking at photos from imagers, there was a faint dust tail as well as ion tail reaching toward M71. I wish I could remember the sky conditions that night as the tail should have been apparent visually under good conditions. The dense star field may have played a part in it.

inverted view

For a good thread by observers tracking Garradd, visit Cloudy Nights. CN Planetary and Solar System: Garradd thread

M71 (NGC 6838) globular cluster, discovered in 1746 by Phillipe Loys de Cheseaux, cataloged by Messier in 1780.

Screen shot from Starry Nights


~ by Erika Rix on October 28, 2011.

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