The Royal Observatory at Greenwich is gearing up for a partial solar eclipse which will be in full effect on Friday morning.
The Moon will pass between the Sun and the Earth starting at 8.24am and ending at 10.41 am. The maximum obscuration of the Sun in London will be up to 84.47% and will occur at 9.31am.
The Royal Observatory Greenwich will open at 8am allowing the public to view the whole of the eclipse.
The Observatory will hold a morning of safe observing through telescopes and solar viewers and the Observatory’s astronomy team and members of the Flamsteed Astronomy Society will be on hand to answer any questions.
The weather forecast for Friday predicts cloud so the view may be obscured. Temperatures are expected to dip around 3C because the Sun's heat is blocked.
A total solar eclipse happens when the Moon’s apparent diameter is the same as or larger than the Sun, blocking all direct sunlight, turning day into darkness. Totality can be seen in a narrow path across the Earth’s surface.
With the Moon obscuring over 80% of the Sun as it passes by, the penumbra will be visible to the naked eye if the Sun is viewed through suitable filters. Observers should never look directly at the Sun.
Popular and safe methods to watch the eclipse are by projecting an image from a telescope or binoculars on to a piece of white card, using a mirror to cast the image on to a screen, or making a pin-hole viewer from card.
Despite occurring somewhere on Earth every 18 months on average, it is predicted that they recur at any given place just once every 360 to 410 years, on average.
The next total eclipse visible in the UK will be September 23, 2090, but the next similar partial eclipse will be visible much sooner, on August 12, 2026.
- The diameter of the Sun is 400 times that of the Moon but it lies 400 times further away. If you are in exactly the right alignment on the surface of the Earth, you will see the two bodies overlap exactly.
- The longest a total solar eclipse can last is 7.5 minutes.
- The width of the path of totality is usually about 160km across and can sweep across an area of Earth’s surface about 10,000 miles long.
- Almost identical eclipses occur after 18 years and 11 days. This period of 223 synodic months is called a saros.
- If any planets are in the sky at the time of a total solar eclipse, they can be seen as points of light.