The planet Venus is making a very rare passage across the face of the Sun.
The so-called transit of Venus began at about 0620 BST (0520 GMT) with the planet's tiny black disc edging over the bright limb of our star.
The phenomenon continues for about six hours, ending around 1224 BST.
People are being warned not to watch it directly as the sun's rays could cause irreversible damage to the eyes.
It is recommended people attend an organised viewing where the transit will be projected on to a screen.
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