The Moon

by Dominic Ford, Editor

The Moon is 20 days old, waning gibbous, and is approaching last quarter. From Newark, it is visible in the morning sky, becoming accessible at around 23:38, when it rises 20° above your eastern horizon. It will then reach its highest point in the sky at 04:06, 50° above your southern horizon. It will be lost to dawn twilight at around 06:56, 35° above your south-western horizon.

12 Jan 2017, 06:35 ESTFull Moon
19 Jan 2017, 17:15 ESTMoon at Last Quarter
28 Jan 2017, 19:08 ESTNew Moon
04 Feb 2017, 23:20 ESTMoon at First Quarter
The Moon

The Moon at First Quarter

The Moon is the Earth's only natural satellite, orbiting it once every 27.3 days, at a distance of 380,000 km (0.00254 astronomical units).

It has almost exactly the same angular size as the Sun – roughly half a degree – a coincidence which means it can occasionally completely cover the Sun's disk to generate a total solar eclipse, but with so little margin that the geometry has to be absolutely exact.

The Moon is the only heavenly body on which surface features can be resolved by the unaided eye. Its mottled pattern of light and dark areas represent two distinct types of terrain. The dark areas are called maria – originally so named because they were thought to be oceans of water, but they are now known to be vast flat volcanic planes. Between the maria, the lighter colored terrain is considerably rougher and more mountainous – the lunar highlands.

To bring the Moon's heavily cratered surface into view, nothing more expensive than a cheap pair of binoculars is needed.




Color scheme