This was a busy sky on an October night! This was October 15, 2020 with Mars at centre just two days past its opposition, and so at its brightest, at magnitude -2.6, in Pisces. In Cetus below, the long-period variable and red giant star Mira (which reaches its maximum brightness only every 332 days) is just past its brightest as well, making it bright enough to be easily naked eye (about magnitude 3.4 here) — it is usually too dim to see naked eye. The name Mira means the “Wonderful”, a name given by Johann Hevelius in 1662, though Mira’s variabilty was discovered in the late 1500s by David Fabricius. Mira is also catalogued as Omicron Ceti. Also in the frame, though faint, are the outer planets Uranus in Aries and Neptune in Aquarius. Both are also near their brightest for the year as both are near opposition as well. Some streaks from geostationary satellites are also visible south of the celestial equator in Cetus, as they flare in brightness for a few minutes near the opposition point as they reflect sunlight back from the point opposite the Sun. The geosats are streaked (even though they are stationary in the sky) because the sky is a stack of tracked exposures, with the camera on a tracker to follow the stars and capture fainter stars and the dim outer planets. Geosats flare in brightness like this only in semi-annual seasons around the equinoxes. The sky is a stack of 4 x 2-minute tracked exposures; the ground is a stack of 4 x 2-minute untracked exposures to keep it sharp, with the two stacks blended and masked in Photoshop. All were at f/2.8 with the 24mm Sigma Art lens and Nikon D750 at ISO 800, and taken from home in southern Alberta. The camera was on the Star Adventurer 2i tracker. Haze and clouds moving in added the star glows. Half an hour later the sky was too cloudy to shoot this.
The large, naked-eye star cluster that makes up most of the constellation of Coma Berenices, aka Mel 111. This is a wide view to simulate the field of binoculars. The galaxies NGC 4565 (left) and NGC 4559 (top left) are visible, as is NGC 4494 between the sliver-like NGC 4565 and the main star cluster. I shot this in deep twilight and retained some of the natural deep blue of the twilight from the earlier shots. The differences in star colours show up. The diffraction spikes are from the lens iris blades from being stopped down to f/4 from the maximum aperture of f/2.8. This is a stack of 7 exposures, each 4 minutes at f/4 with the 200mm Canon lens and Canon 6D MkII at ISO 800, unguided on the AP Mach 1 mount.
A framing of the Milky Way from Altair in Aquila at bottom up to Albireo in Cygnus at top. The prominent dark nebulas B142 and B143, aka Barnard's E, are right of yellowish Tarazed above Altair. The constellation of Sagitta the Arrow is at centre, and to the right of Sagitta in the dark dust lanes is the Coathanger asterism, aka Collinder 399. Above Sagitta is the green disk of the Dumbbell Nebula, Messier 27, in Vulpecula the Fox. Above it, at upper left is the star cluster NGC 6885. And as a bonus, one of the stars in Sagitta is actually the globular cluster Messier 71. The field is about 24° by 16°. This is a stack of 6 x 3-minute exposures with the Rokinon RF85mm lens at f/2.8 and Canon R5 at ISO 800, on the Star Adventurer tracker. Taken from home on Sept. 27, 2022. Stacked and aligned in Photoshop. A mild star glow effect added with Luminar AI.
