The moon turned blood red yesterday as the Earth passed directly between it and the sun, creating a shadow that stopped solar rays reaching the surface and a total lunar eclipse that won't be seen again until 2021.

What is a total lunar eclipse and how does it occur?

The eclipse, which began about 4.34pm yesterday and reached totality at 5.41pm, occurred when the moon was at its closest point to Earth - making it a supermoon, so it appeared 14 per cent larger and 30 per cent brighter. The entire eclipse exceeded three hours. Totality - when the moon is completely bathed in Earth's shadow - lasted an hour. Everyone could see the supermoon but the entire eclipse was visible only in North and South America, and across the Atlantic to western and northern Europe.

Why does a total lunar eclipse not occur at every full moon?


A full moon occurs every 29.5 days when Earth is directly aligned between the sun and the moon. The moon's orbital path around the Earth takes place at an angle of 5 degrees to Earth's orbital plane around the sun, otherwise known as the ecliptic. Lunar eclipses can only take place when a full moon occurs around a lunar node, the point where the two orbital planes meets. This means total lunar eclipses do not occur as frequently because the Earth's orbit around the sun is not in the same plane as the moon's orbit around the Earth.

This combination photo shows the totally eclipsed moon, centre, and others at the different stages during a total lunar eclipse. Photo / AP
This combination photo shows the totally eclipsed moon, centre, and others at the different stages during a total lunar eclipse. Photo / AP

What is a blood moon and is it different to a total lunar eclipse?

The moon's usual bright white hue may turn a burnt red-orange during a total eclipse because sunlight passing through the Earth's atmosphere is bent towards it. Colours in the spectrum with shorter wavelengths are blocked and filtered away while those with longer wavelengths such as red and orange can pass through. The depth of the deep blood red varies during each eclipse depending on how clear the atmosphere is at the time. Whenever this process of refraction happens, the moon is given the nickname "blood moon".

Some people are also calling this moon a wolf moon ...

The moniker "Wolf Moon" was given to every January moon by Native Americans. The early Native Americans didn't record time using months of the Julian or Gregorian calendar. Instead tribes gave each full moon a nickname to keep track of the seasons and lunar months. Most of the names relate to an activity or an event that took place at the time in each location. The January moon was named Wolf Moon because villagers used to hear packs of wolves howling in hunger around this time of the year. Its other name is the Old Moon.

The moon during a total lunar eclipse. Photo / AP
The moon during a total lunar eclipse. Photo / AP

Blood moons and lunar eclipses of the past

Christopher Columbus, an Italian explorer, created fear in 1504 after he used knowledge of an upcoming blood moon to convince the Arawak Indians to help him while stranded in Jamaica. He led them to believe their lack of support would anger God and result in a blood moon in the sky. When the moon began to "bleed", the Arawak Indians were fooled into giving Columbus and his crew food. In more recent years, the total lunar eclipse of July 16, 2000 - which was seen in the Pacific Ocean, eastern Asia and Australia - was one of the longest to ever be recorded, lasting 1 hour 46 minutes.