Tomorrow morning (Monday 28th September 2015) will see a full Moon in the perigee position (passing close to the Earth at 363 396 km’s and being a full Moon can be referred to as a supermoon). The lunar eclipse will occur when light from the sun will be blocked by Earth starting at approximately 03h07 and ending at 06h27 with a maximum at 04h11-05h23. In a total lunar eclipse, the Earth, Sun and Moon are almost exactly in line and the Moon is on the opposite side of the Earth from the Sun.
The Moon’s path around the Earth is elliptical, with one side of the orbit closer to Earth than the other. The side closest to the Earth is called the perigee and the side farthest from the Earth is known as the apogee.
On average, the Moon is about 384,500 km from the Earth. However, because of the elliptical shape of the Moon’s orbit, the actual distance varies throughout the year, between 363,396 km at the perigee and 405,504 km at the apogee.
The full Moon dims quite a lot as it moves into the Earth’s shadow, but usually remains visible (lit by sunlight that moves through the planet’s atmosphere).
Why does the Moon appear red?
Light is filtered by the Earth’s gaseous atmosphere – the green to violet range of colours gets filtered out more than the red and folk on Earth will see the Moon as rusty, blood red or dark grey (see the photograph below).
There have been just five supermoon lunar eclipses since 1900 and the next won’t happen until 2033.