Skygazers can expect to see a blue moon – the second full moon in a calendar month – orbiting closer to the Earth than usual.
The moon will appear 30 per cent brighter and 14 per cent bigger on Wednesday making it a ‘super moon.’
And the event is also coupled with a total lunar eclipse for the first time in more than 150 years.
What is a lunar eclipse?
A total lunar eclipse takes place when the Earth comes between the Sun and the Moon and covers the Moon with its shadow. When this occurs, the Moon can turn red, the reason for the name Blood Moon.
A total eclipse of the Moon occurs when the Full Moon when the Sun, Earth and Moon are aligned to form a line.
The last total lunar eclipse happened in 2015 and the last time we experienced a super blue blood moon was in 1866 – more than 150 years ago.
A total lunar eclipse usually happens within a few hours and totality can range from a few seconds to 100 minutes.
In a total lunar eclipse, there are seven stages:
- Penumbral eclipse starts: This begins when the penumbral part of Earth’s shadow starts moving over the Moon, however this cannot be seen by the naked eye
- Partial eclipse begins: Earth’s umbra starts covering the Moon, making the eclipse more visible
- Total eclipse begins: Earth’s umbra completely covers the Moon and the Moon can turn red, brown or yellow in colour
- Maximum eclipse: This is peak of the total eclipse and the best time to view the lunar event
- Total eclipse ends: At this stage, the Earth’s umbra starts to move away from the Moon’s surface
- Partial eclipse ends: Earth’s umbra completely leaves the Moon’s surface
- Penumbral eclipse ends: At this point, the eclipse ends and Earth’s shadow completely moves away from the Moon
Even though during a lunar eclipse, the Earth blocks sunlight from directly reaching the surface of the Moon, the Moon is still visible to the naked eye.
This is because the Earth’s atmosphere bends sunlight and indirectly lights up the Moon’s surface.
What makes the Total Lunar Eclipse and Super Blue Blood Moon special?
What makes this lunar eclipse special is the fact the eclipsed Full Moon on Wednesday, January 31 will be a Blue Moon – the second of two full moons in one calendar month.
The Moon will also be very close to the Earth, making it a Super Moon. It will be 223,068 miles (358,994 km) from Earth, compared to the average distance of 238,855 miles (384,400km), according to NASA.
Supermoons happen when the moon’s perigee, its closest approach to Earth in a single orbit, coincides with a full moon.
The Royal Observatory in Greenwich said: “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 – sometimes red or possible virtually invisible.
“Dust in the atmosphere blocks out the higher frequency blue light waves, but the longer wavelength of red light comes through.”
The next lunar eclipse will happen on July 27-28 2018 and will be visible across much of Europe, Asia, Australia, Africa, southern parts of North America and South America.