What is a lunar eclipse?

An eclipse of the Moon occurs when the Earth lies directly between the Sun and the Moon and the Moon lies in the shadow of the Earth.

What are the different types of lunar eclipse?

For a total lunar eclipse to happen, all three bodies – the Sun, the Earth and the Moon – lie in a straight line. This means that the Moon passes through the darkest part of the Earth’s shadow - the umbra.

But a lunar eclipse isn't always 'total'. There are actually three different types of lunar eclipse.

Total lunar eclipse

During a total lunar eclipse, the Moon usually turns a deep, dark red because it is illuminated by light that has passed through the Earth's atmosphere and has been bent back towards the Moon by refraction.

Impact of a Meteoroid During the Total Lunar Eclipse © Rafael Ruiz.jpg
Impact of a Meteoroid During the Total Lunar Eclipse by Rafael Ruiz, Astronomy Photographer of the Year 2019

Partial lunar eclipse

During the partial phase of the eclipse, part of the Moon travels through the Earth's full 'umbral' shadow.

However, on this occasion only a very small section of the Moon will be covered by the umbra at maximum eclipse, though the whole northern half of the Moon will be darkened by the penumbral shadow.

Jon Culshaw is a judge for the Astronomy Photographer of the Year competition

Penumbral lunar eclipse

A penumbral lunar eclipse occurs when the Moon travels only through the outer, fainter part of the Earth's shadow, or 'penumbra'. This happens when the Earth moves between the Sun and Moon but the three do not form a perfectly straight line.

OM-84200-21_The Penumbral Lunar Eclipse and the New Born Rime © Hailong Qiu.jpg
The Penumbral Lunar Eclipse and the New Born Rime by Hailong Qiu, Astronomy Photographer of the Year 2020

The penumbra causes only a slight darkening of the Moon's surface, with the Moon still exposed to some direct sunlight, so this type of eclipse is easy to miss.

When is the next lunar eclipse in the UK?

The table below shows lunar eclipse dates in 2022, including the upcoming total lunar eclipse in May 2022.

16 May 2022 Total lunar eclipse 
8 November 2022 Total lunar eclipse (not visible in UK)

16 May 2022 total lunar eclipse

On 16 May 2022 a total lunar eclipse will be visible over South America, most of North America and parts of Europe and Africa.

People in the UK will not be able to see every part of the eclipse, but will still be able to see the lunar eclipse at totality when the entire Moon turns red.

The Moon will start to enter the Earth’s shadow just after 2.30am BST, and the full eclipse will occur just before 4.30am.

The entire eclipse lasts for more than five hours, ending at 7.50am. However, observers in the UK will only be able to see the eclipse from 2.32am – 5.10am as the Moon will have set below the horizon by the end of this period.

The optimal viewing time to see the eclipse is between 4.29am and 5.06am. This is the period of totality in London, where the Moon lies entirely in the Earth’s umbra (full shadow) appearing red. The whole of the Moon will still be visible.

When is the next full Moon?

How to see the lunar eclipse

See astronomer Tom Kerss's top tips for observing and photographing a lunar eclipse in the video below.

What time is the 2022 total lunar eclipse?

The table below lists the timings for the whole 2022 eclipse as seen from the Royal Observatory's home in Greenwich, London. They might differ by a few minutes for other parts of the UK.

Local time (BST) in London




Penumbral eclipse begins

The Moon will start to enter the Earth’s penumbra (area of partial shadow) and start to darken

Low in the south west


Partial eclipse begins

The Moon will start to enter the Earth’s umbra (area of full shadow) and leave its penumbra and will darken considerably, almost as if it is changing its phase from full moon to waning crescent in just over an hour

Very low in the south west


Full eclipse begins

The Moon has completely entered the Earth’s umbra and starts to turn red

Very low in the south west



Maximum eclipse

This is when the Moon is closest to the centre of the Earth’s umbra. The maximum eclipse in London is at 5.06am as this is the point at which the entire Moon is still above the horizon at the greatest magnitude Moonset is at 5.10am. The actual maximum eclipse is at 5.11am; however the Moon will be below the horizon at this time

Below horizon


Full eclipse ends

The Moon will start to leave the Earth’s umbra and enter its penumbra losing its red colour

Below horizon


Partial eclipse ends

The Moon has left the Earth’s umbra and has completely lost its red colour. One side starts to get lighter whilst the other is still very dark as it enters the Earth’s penumbra, almost as if it is changing from a waxing crescent to a full moon in around an hour

Below horizon


Penumbral eclipse ends

The Moon will look slightly darker than usual and has now left the Earth’s penumbra

Below horizon

When was the last lunar eclipse in the UK?

19 November 2021 - partial lunar eclipse

This eclipse was unusually long, lasting over six hours in total from the moment the Moon entered the Earth's shadow or 'penumbra'.

The very early part of the eclipse was visible in the UK, but because of the timings the Moon had set before the eclipse reached its maximum.

16 July 2019 - partial lunar eclipse

A partial lunar eclipse took place in the UK on 16 July 2019, coinciding with the 50th anniversary of the Apollo 11 launch. Some of the eclipse was visible over parts of Europe, Asia, Australia, Africa, select parts of North America, South America and Antarctica.

20-21 January 2019 - total lunar eclipse

A total lunar eclipse took place in the UK in the early hours of 21 January 2019. The eclipse happened during the first full moon of the year, earning it the nickname 'Super Wolf Blood Moon'.

Royal Observatory Greenwich broadcast a live stream of the total eclipse on Facebook.

How often do lunar eclipses happen?

A lunar eclipse happens between two to five times a year, with a total lunar eclipse occurring at least two every three years. 

Why doesn't a lunar eclipse happen every month?

A lunar eclipse occurs during the full moon phase but an eclipse does not happen every month, even though the lunar cycle is 29.5 days. This is because the moon’s orbit is inclined by 5˚ relative to the Earth’s orbit. This means that as it travels around the Earth it also moves up and down in its orbit. 

How long does a lunar eclipse last?

Since the Earth is around four times wider than the Moon, its shadow can darken the moon for up to five hours depending on conditions. Lunar eclipses can be seen between two and five times every year – from somewhere on the Earth’s surface. Total lunar eclipses are much rarer from one particular location.

What is a supermoon?

When the moon is close to perigee, the closest point to Earth in its orbit, it makes the moon appear slightly larger than usual. This phenomenon has been dubbed a “supermoon”. Much like “blood moon” it is not an official astronomical term. A “supermoon” will appear up to 7% larger than a regular full moon.

Find out more about supermoons

Why is a lunar eclipse called a 'blood moon' – and are they actually red?

People sometimes refer to a lunar eclipse as a ‘blood moon’ because of the way the Moon can turn a deep coppery red colour during its eclipse.

However, the colour of the Moon during totality will depend on the global state of dust in the Earth’s atmosphere. Dust in the atmosphere blocks out the higher frequency blue light waves, but the longer wavelength of red light is able to still come through.

PS-41196-1_Runner-Up_Observe the Heart of the Galaxy © Tian Li.jpg

Guide to the night sky

Plan your stargazing year ahead with the Royal Observatory's astronomy calendar