An image with some unusual colour contrasts for a deep-sky image — with blue Bellatrix, a green comet, and the huge red Lambda Orionis nebula. This is Comet ATLAS (C/2020 M3) seen here as the green glow above the bright blue star Bellatrix in the shoulder of Orion, and approaching the large diffuse red nebula surrounding the “head” star of Orion, Lambda Orionis. aka Meissa. The large nebula complex is catalogued as Sharpless 2-264. At right, above the comet, is the smaller emission and reflection nebula catalogued as vdB (vandenBurgh) 38. The sparse star cluster surrounding Lambda Orionis is Collinder 69. This was the night of November 15/16, 2020, with the comet moving rapidly northward a day after its closest approach to Earth and three weeks after its perihelion, or closest approch to the Sun. On the next nights the comet would have been within the nebula. This is a stack of 8 x 8 minute exposures without a filter, blended with 6 x 15-minute exposures through an Optolong L-Enhance narrowband nebula filter, to bring out the faint nebulosity. The comet image itself is from just one of the filtered frames layered and masked to reveal just the comet. But even in the single 15-minute exposure its image trailed slightly as its motion was quite rapid. I used a filtered shot for the comet as its green/cyan glow did pop out more than in the unfiltered shots, though the more usual cyan colour of a comet has been altered a little by the narrowband filter and its bandpass of the green OIII lines. All were with the William Optics RedCat 51mm astrograph at f/4.9 and with the Canon EOS Ra, with the filtered shots at ISO 3200 and unfiltered shots at ISO 800. Images were autoguided, with dithering, using the Lacerta MGEN3 stand-alone autoguider. I also used its polar alignment routing this night to refine the mount’s polar alignment and it seemed to work! All images stacked, aligned and blended with Photoshop.
Comet C/2022 E3 (ZTF) in the constellation of Auriga on the night of Feb 8, 2023. The comet is the small cyan-coloured glow above centre. It was technically in Auriga but heading south into Taurus and in front of the Taurus Dark Clouds here at centre. Mars is the bright orange object right of centre. At right are the Pleiades and Hyades star clusters, the latter with reddish Aldebaran. Other Messier-catalogue star clusters are in the frame: M36, M37 and M38 in Auriga and M35 in Gemini. The red emission nebulas in this part of the Milky Way also stand out, notably the California Nebula, NGC 1499, at top in Perseus, and the Flaming Star Nebula, IC 405, in Auriga at centre. At bottom is the large faint nebula around Lambda Orionis, or Meissa, in Orion. Capella is at top; Castor and Pollux are at left. This is a stack of 4 x 1-minute exposures at ISO 1600 with the red-sensitive AstroGear modified Canon R and with the RF28-70mm lens at f/2.8 and 28mm. This is one segment of a Milky Way panorama taken this night, from Dinosaur Provincial Park, using the Star Adventurer tracker.
Comet Lovejoy, C/2014 Q2 amid the clusters, nebulas and dark dust clouds of Taurus and Perseus, on Friday, January 16, 2016. Its long blue ion tail stretches back at least 15°, almost to the open cluster NGC 1647 on Taurus at the left edge. At centre is the Pleiades star cluster, M45; at top right is the red California Nebula, NGC 1499, in Perseus, while the field is filled with the dark dusty lanes of the Taurus Dark Clouds. At left is the red giant star Aldebaran amid the V-shaped Hyades star cluster. I turned the field 90° clockwise from the original orientation, putting the “bottom” of the field (the area farthest south and closest to the horizon) at the left edge. North is to the right here. This perhaps provides a “more natural” orientation to the comet for most people. This is a stack of 10 x 2 minute exposures with the Sigma 50mm lens at f/2.5 and filter-modified Canon 5D MkII at ISO 1600. Tracked on the Sky-Watcher Star Adventurer, but not guided. Shot from City of Rocks State Park, New Mexico, Jan 16, 2015.
