A crowd gathered at Dunedin's observatory has been rewarded with a view of the transit of Venus - one of the rarest astronomical events which won't occur again until 2117.
A ripple of excitement went through the crowd of about 100 people when the planet was first observed crossing the sun this morning.
People are taking turns using the Beverly-Begg Observatory's filtered telescopes or viewing the transit through dark glasses.
Experts said Otago, Southland and Fiordland would be the best place to view the event.
In the North Island, people in Auckland, Waikato, Gisborne and Hawkes Bay could get brief windows of clear sky this morning to view Venus moving across the face of the Sun. Rain clouds are expected to shroud the island later in the day, MetService forecaster Derek Holland said.
"If you have a fine spell where you are, you need to rush out and grab it.''
People are warned that staring directly at the Sun could cause serious eye damage.
The Royal Australian and New Zealand College of Ophthalmologists encouraged people to watch the event online or on television.
"No matter what recommended technique you use, do not stare continuously at the Sun and do not use sunglasses alone as they don't offer your eyes sufficient protection.
"There are no pain receptors on the retina so you won't even know you are doing damage.''
Children's eyes were even more easily damaged.
The transit starts at about 10.15am, with the middle of the event around 1.30pm. Venus reaches the far edge of the Sun by 4.25pm and the event ends around 4.45pm.
According to the Royal Astronomical Society of New Zealand website, Venus will be visible as a small black dot on the Sun's disk. It will be very small _ only three per cent of the diameter of the Sun. It will be an intensely black spot in contrast to the bright solar disk which will make it stand out.
Anyone wanting to view the transit could link up with their local astronomical society, which are likely have specially prepared equipment allowing a larger image of the Sun to be viewed (weather permitting).
Numerous websites will also track the event.
It is the same occurrence that Captain James Cook was dispatched to Tahiti on HMS Endeavour to observe in Tahiti June 3, 1769.
