A partial solar eclipse will be visible to inhabitants of Singapore on Sunday, June 21 at about 4pm, but extensive cloud cover and rainfall is threatening to spoil the event for sky gazers.

This is what the maximum eclipse would look like, with some 17 per cent of the sun covered:

This is due to the full annular solar eclipse phenomenon not being completely visible from regions near the equator.

In its complete form, the moon partially obscures the view of the sun, allowing a ring of star fire to escape its edges.

The annular solar eclipse happens when the moon is farthest away from Earth in its orbit, and therefore, appears smaller in our skies relative to the sun.

This is different from a full solar eclipses, when the moon completely covers the sun's disk, owing to the closer position of the moon to Earth, which makes it appear to be the same size as the sun.

In Singapore, the start of the eclipse will be at 3:04pm and will last till 4.54pm.

The maximum eclipse is at 4.03pm.

Many countries will see it

A complete "ring of fire" will be visible from central Africa and through Asia.

Many other locations, from southeastern Europe to the northern tips of Australia, will experience a partial annular eclipse.

The shadow moving across the image indicates where at least a partial eclipse will be visible.

The moving dot marks the line of totality -- the path along which the annular eclipse will last the longest.

At the peak of the eclipse, the moon will block 99.4 per cent of the sun as the pair graces the skies of northern India.

Those keen on witnessing the solar eclipse are advised to use shades.

The last annular eclipse took place over Singapore on Dec. 26, 2019, and the phenomenon did not disappoint:

Top photo via Wikipedia