Stargazers all over the world are setting up special telescopes and passing out cardboard eclipse glasses to view a once-in-a-lifetime celestial cameo - Venus passing in front of the sun.

The transit of Venus is a planetary spectacle that will not occur again until 2117.

Earth's second nearest neighbour will not significantly block the sun's light, but it will give our closest star a moving beauty mark.

The transit is happening during a six-hour, 40-minute span starting after 10pm in the UK.

What stargazers can see and for how long depends on what the sun is doing in their region during that window.

Sunny spots in Hawaii, Alaska, eastern Australia and eastern Asia will get the whole show.