Horsehead Nebula

About the object

The Horsehead in Orion, the most famous dark nebula in the sky. The 'head' itself is a dense cloud of dust blocking the glowing band of hydrogen IC 434 behind it; the star Sigma Orionis lights that band. In the same field are the bright star Alnitak, the left star of Orion's belt, and the Flame Nebula NGC 2024. In a few million years radiation from nearby stars will disperse the cloud and the Horsehead will be gone.

Distance: about 1,400 light-years, apparent size in the sky: 60′ × 10′, голова 8′, constellation Orion.

How it was shot

Everything here was shot with a DWARF Mini smart telescope from a balcony in a city in Ukraine: light-polluted sky, only the eastern half of it visible, and a roof overhang that cuts off the south. 6 nights (all in September), 6 sessions, 328 frames with exposures of 60, 90 and 180 s, a dual-band Hα/OIII filter that passes only the glow of hydrogen and oxygen and blocks most of the city light pollution. The stack holds 6 h 2 min of light; the longest night, 20 September, gave 2 h 8 min. The goal for this object is 8 h, 75% done so far. First night 11 September 2026, last one 21 September 2026.

Horsehead Nebula in the night log: 10 September, 11 September, 17 September, 18 September, 19 September, 20 September.

How it went

The Horsehead turned out to be the most demanding on exposure: at 180 seconds the device rejected every second frame, at 90 a third, and only at 60 seconds did the loss drop to an acceptable level. That ladder later became the standard for all nebulae. Bright Alnitak nearby throws a halo on long frames. Six nights gave the silhouette of the head and the Flame, but the goal is still gathering light.