Moonrise magic: why Friday?s lunar eclipse offers an unusual twilight show for most of Australia

As the full moon rises on Friday night it won't be as lovely and bright as usual - but it will be fascinating. Across most of Australia the moon will be partially shrouded in Earth's shadow, so it will undergo a partial lunar eclipse as it rises.

A lunar eclipse happens roughly every six months somewhere on Earth. For most of the year, the moon's orbit takes it above or below Earth's shadow but, during an eclipse, the full moon travels through it.

If the entire moon travels through the shadow, it is a total lunar eclipse. Friday's eclipse won't quite make it to totality and instead will be a very deep partial eclipse.

The fact that Friday's event occurs at moonrise for viewers in Australia means this will be a different experience to what is typically seen when watching a lunar eclipse.

The moon will be low in the sky for much of the eclipse, meaning you'll need an unobstructed view towards the east-north-eastern horizon, perhaps with the aid of an elevated viewing position. In the opposite part of the sky, the sun will be setting and Venus, Saturn and Jupiter will be visible.

The sun sets a few minutes after the moon rises, so for the first half hour or so the eclipsed moon, low on the horizon, will be battling the bright twilight sky.

As the moon climbs higher and the sky darkens we will have a lovely view of the eclipse's final phase. We can watch the moon emerge from Earth's shadow and return to its full brightness.