I have always enjoyed observing comets and have sketched several nice ones over the last decade. More recently with my foray into the world of DSLR photography I have also taken a couple pictures of comets such as C/2011 L4 Pan-Starrs in the evening sky. With a few clear nights this week as the monsoon season wraps, I made a couple observations of Comet Jacques (C/2014 E2) which has been in the northern sky for a few months. This comet was discovered this past March, and reached perihelion (its closest point to the Sun) on July 3rd 2014, passing Venus ten days later at a fairly close 7.9 million miles! On August 28th, the comet made its closest approach to Earth at 52,415,761 miles, which is comfortably, a little more than half the distance to the Sun.
Two nights ago, on Sept 2 (UT) I took my first pictures of a comet through a telescope! Using my 140mm refractor, I captured ten 20-second images of the comet, at ISO 1600 using the program BackyardEOS. Below is a single image of the comet with the levels and contrast adjusted in photoshop.
My intention in taking 10 exposures was to stack them, bringing out any detail that may not be visible to the eye or in a single exposure. In the stacked image below, you can see that I aligned the images on the comets nucleus and as a result the stars appear to trail. There is a brighter inner coma around the nucleus as visible in the above image, and stacking the exposures revealed a fainter outer envelope of glowing gas.
Being my first try with a comet, I think this little experiment turned out quite well. This attempt was all about getting my feet wet imaging a comet with a DSLR. Next time I will pay more attention to timing my exposures in order that the star trails are more uniform, and will also spend a little more time figuring out the optimal exposure.
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