Very Faint Comet 46P/Wirtanen

Mike Olason
Location of photo
Denver, Colorado
Date/Time of photo
7 July 2018, 0919UT
11" SCT f/6.4 and STF-8300M CCD Camera
This image is the result of averaging 14 five minute images of Comet 46P/Wirtanen which is magnitude 19.8 in this image and is 153 million miles from Earth. Don't let this very faint image of 46P disappoint you though, Comet 46P/Wirtanen is predicted to reach about magnitude 3.5 when it will only be 7 million miles from Earth on December 16 this year. The great thing about that is the comet will be 50 degrees above the western horizon when the Moon sets at 8UT (1AM in Denver) and over 6 hours will move 1 degree across Earths night sky. With binoculars the comet should have a nice tail or at least be a nice fuzzy green object in your binoculars. The other great thing about this comet is that it should be brighter than magnitude 6 and visible in the night sky from mid November until mid January. Of course, 46P is a comet and could be brighter than expected or it could be fainter than expected. If it brightens as expected it would be a great binocular or small telescope project for astronomy clubs and school programs. 46P/Wirtanen is at perihelion in its 5.43 year orbit on 12 December when it will be 98 million miles from the Sun.
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Mike Olason

About Mike Olason

I started imaging comets in 1994 with an ST-5 CCD Camera and an 11" SC Telescope. Since then the CCD cameras have changed (ST-7, ST-402ME and STF-8300M), but I am still using the 11" SC Telescope. Naturally I have used a lot of smaller telescopes to obtain larger fields of view. I live south of Denver at an elevation of 6150 feet which allows me to image comets down to almost magnitude 21 on a perfect night. Unfortunately ChemTrails have turned Denver cloudy and dry. I use the camera software CCDOps to process my images. All I do to each image is dark subtraction and flat field, stack images as required to show faint comets, contrast/bright adjust the final image and maybe use a median filter to reduce the image noise. The result is an image that reflects reality and will never win any picture of the day award. If you would like to use my images for a project or ask a question send me an email to "".
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