Comet Leonard (C/2021 A1) on the morning of December 10, 2021, with a 200mm telephoto lens for a field of view of 10° x 6.8°. The tail appears to be about 3.5° long here. Taken about 6:30 am MST with the comet as high as it would be, though the sky is already beginning to brighten with the blue of dawn twilight. The distinctive cyan tint of a comet's coma is prominent. The comet was in Serpens at the time, with the magnitude 2.6 star Alpha Sepentis (aka Unukalhai) at far right (I framed the image to include the star). The reddish double star 47 Serpentis is below the comet. This is a stack of 4 x 2-minute exposures at f/2.8 (wide open) with the 200mm Canon EF lens on the Canon EOS Ra camera at ISO 800. The comet has trailed a bit over the 4 minutes of exposure time as it was just past its closest to Earth and moving quite quickly eastward toward the Sun at this time. Taken from home in southern Alberta.
Comet Leonard (C/2021 A1) on the morning of December 10, 2021, with a 135mm telephoto lens for a field of view of 10° x 15°. The tail appears to be about 4° long here. Taken about 5:45 am MST. The distinctive cyan tint of a comet's coma is prominent. The comet was in Serpens at the time. This is a stack of 4 x 1-minute exposures at f/2.8 with the 135mm Canon EF lens on the Canon EOS Ra camera at ISO 1600. The ground and area of sky closest to the ground comes from a single exposure to minimize blurring and the trailing of stacked stars from atmospheric refraction. The rest of the sky stacked with a Median stack mode to help eliminate satellite trails. Taken from home in southern Alberta.
This is the line-up of planets across the southwestern sky on December 6, 2021, consisting of (L to R): Jupiter, Saturn and Venus, with the 2.5-day-old waxing crescent Moon in conjunction below Venus. The Moon had eclipsed the Sun two days before on December 4, when it was on the ecliptic. Two days later it was below the ecliptic line. Jupiter and Saturn are in Capricornus, with its stars all visible here in the evening twilight. The three planets are nicely equally spaced. Such an array makes the ecliptic line visible. The location is overlooking the Bow River, on the Buffalo Rock Road on the Siksika Nation near Blackfoot Crossing, Alberta. This is a blend of 4 exposures: 8s, 4s, 2s and 1s to retain details and colours in the brightest part of the twilight sky at right and on the Moon's disk lit with Earthshine. All were at f/2.8 and ISO 400 with the Canon RF 28-70mm lens at 33mm and red-sensitive Canon EOS Ra. Taken in "blue hour." I added a mild Orton glow with Luminar AI. The 4 images were masked initially with ADP Pro but I then painted the masked manually to eliminate most of the sky from the shorter exposures leaving just the brightest part of the sunset glow without stars, so avoid multiple star images from the untracked camera. This is the version with lines and labels added in to mark the ecliptic and constellation pattern. There is a version without the overlays.
