Two Comets Pass by The Dusty Pleiades and the Fiery California Nebula (with labels)
Comet C/2017 O1 ASAS-SN, the green dot center bottom right, and Comet C/2015 ER61 PanSTARRS the up and down white dusty streak just below and to the right of the blue Pleiades pass through this colorful area of the constellation Perseus.
This image has approximate paths overlaid on the image showing the movement of the comets in the night sky. The bend in C/2015 ER61 is the point to which it changes direction in the night sky and moves retrograde or backwards from it's normal movement. There are a couple objects in the night sky that are located in our solar system do this, most notably planets, their retrograde motion was a crucial part of observations that led early astronomers to the conclusion that the Sun was at the center of the solar system.
How we discovered the Sun was at the center of the solar system: io9.gizmodo.com/how-we-came-to-recognize-the-sun-as-the-c...
Comet C/2017 O1 ASAS-SN: www.cometwatch.co.uk/bright-comets-of-2017/comet-c2017-o1...
Comet C/2015 ER61 PanSTARRS: theskylive.com/c2015er61-info
Images were taken between 12:13-1:16am PDT on 9/23/2017
10x240" Light at 1600ISO
Camera: Canon 6D Hutech UV/IR Mod
Lens: Zeiss 85mm f/1.4 Milvus @f/4
Mount: Celestron Advanced VX
Guide Scope: Orion Mag Mini With SSAG
Capture Software: Backyard EOS
Processing: Photoshop CC, Registar
Location: Los Padres National Forest, CA