Moon

About the object

The Moon, our only natural satellite and the most convenient balcony target: bright, large, reachable from any city under any light pollution. Its average distance is about 384,000 kilometres; the light takes a little over a second to arrive. It is most interesting not at full phase but near the terminator, the line between day and night: there the shadows are long and craters, mountains and rilles reveal the relief. The terminator shifts every night, so the same crater never looks the same twice.

Apparent size in the sky: ≈ 31′.

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. The Moon was observed over 16 nights (6 nights in August, 7 in September and 3 in October) in 35 sessions, 10,496 frames with exposures from 2 ms to 50 ms, filter: dual-band Hα/OIII. For the Moon, the Sun and the planets the telescope records short video and the sharpest frames are stacked, so a few good minutes of steady air matter more than hours of exposure.

Moon in the night log: 23 August, 25 August, 28 August, 29 August, 30 August, 31 August, 1 September, 2 September, 4 September, 21 September, 24 September, 28 September, 29 September, 3 October, 4 October, 6 October.

How it went

The Moon is shot differently from nebulae: exposures of thousandths of a second, hundreds of frames, and only the sharpest, caught in a moment of steady air, go into the stack. So the main enemy here is not light pollution but the city's heat: the air above the roofs trembles and the disk 'swims'. The best frames come before dawn, when the roofs have cooled. A separate experiment is the mineral Moon, where boosted colour shows differences in the composition of the maria.