Last chance to view rare Venus transit

PUBLISHED : Wednesday, 06 June, 2012, 12:00am
UPDATED : Wednesday, 06 June, 2012, 12:00am


Stargazers have their last chance to see the transit of Venus today - and Hongkongers are invited to watch the astronomical event with the help of experts at a special free event.

The transit occurs when the orbit of the second planet from the sun takes it between the sun and the earth. The astronomical event happens in pairs, eight years apart, then isn't visible again for more than a century. The next transit of Venus will take place in 2117.

Venus will appear as a tiny black disc moving across the surface of the sun and will be visible from Hong Kong from 6.12am to 12.49pm.

Astronomers are keen to remind members of the public that looking directly at the sun is extremely dangerous and can quickly cause permanent eye damage or even blindness, so special equipment must be used.

One option is to visit the Avenue of Stars in Tsim Sha Tsui, where experts from the Space Museum, the Astronomical Society, the University of Hong Kong's science faculty, and the Ho Koon Nature Education and Astronomical Centre will help members of the public view the event using filter-equipped telescopes and other equipment from 6am to 1pm.

Space Museum's curator Chan Ki-hung says the transit is one of the rarest astronomical phenomenons, 'even [rarer] than the solar eclipse, which we had just weeks ago'.

'It's rare because if you want to see solar eclipses, you can travel to different parts of the world and see it twice a year, but you will only see a transit of Venus twice in a century in particular locations,' he said.

Sky-watchers will be looking for a very thin arc of light, called the aureole, which can only be seen when Venus appears to just touch the edge of the sun's disc. The Observatory will broadcast a live webcast of the transit on its website.

Last month's annular solar eclipses, the first visible from Hong Kong since 1958, proved to be something of a disappointment, with clouds obscuring the view of those hoping to catch a glimpse. But the prospects look a little better tomorrow, with the Observatory predicting fine weather with a chance of isolated showers.

The last transit of Venus in 2004 - the first since the invention of broadcast media - was visible from Europe and most of Asia, although not eastern China.

The first scientific observation of the transit was in 1631, when English astronomers Jeremiah Horrocks and William Crabtree were able to predict and view the astronomical event.

The transit of Mercury, the planet nearest the sun, will be visible in 2016.