cloudy sunset on the sea

Captain Cook: Mapping the Transit of Venus

2018 has seen us celebrate 250 years since the intrepid Captain Cook set off on his journey. 2019 will mark the 250th anniversary of James Cook, Joseph Banks, Charles Green and Daniel Solander’s successful mapping of the Transit of Venus.

What is the Transit of Venus?

The transit of Venus occurs when the planet passes directly between Earth and the Sun. As it passes in front of our star, Venus appears as a black dot moving across the bright, fiery surface. It usually takes several hours to pass over the sun and happens very infrequently.

A transit is very similar to when we experience solar eclipses with the moon. But, because Venus is much further away from Earth, the planet doesn’t block out the whole sun and appears to move much slower.

Transits happen in pairs, roughly 8 years apart. The last transit happened in June 2012, but before that it hadn’t been seen since 1874 and 1882. There won’t be another transit of Venus until 2117.

the transit of Venus across the sun

Captain Cook and the Transit of Venus

Cook, Banks, Green and Solander observed the Transit of Venus in 1796. The aim of Cook’s first voyage that we’ve been celebrating this year was to observe and map this natural phenomenon.

They wanted to map the transit to help calculate the size of the solar system. This was invaluable information for nautical navigation.

If astronomers and other scientists could map the transit of Venus, they would be able to use the Principles of Parallax to better calculate the scale of the solar system. Scientists in 1761 had tried and failed to capture and report the data, so it was down to Cook and the crew to get it right. If they were unsuccessful, the mystery would remain unsolved in their lifetime.

The crew sailed to Tahiti and constructed an observatory. It was from there, appropriately named Point Venus, that the men witnessed the movement of the planet across the sun.

2019 marks the 250th anniversary of this historic moment and the mapping of New Zealand. Here in Whitby, we’ll be keeping the Cook celebrations going with exciting events in the town. The Captain Cook Memorial Museum will be hosting a very special exhibition for the occasion – Botanical Endeavours: What did Joseph Banks do on the Endeavour voyage?

breakwaters at Whitby

Cook 250 year celebrations

After the explorers had mapped the celestial event, they then went on to explore lands previously unknown to Western scientists. Cook is famed for discovering Australia and New Zealand. Of course, the land has always been there with many people living there, but Cook and the team were the ones who brought news of their existence back to the UK and Europe.

It’s that discovery that we’ve been celebrating all year in Whitby. The #Cook250Whitby events attracted lots of tourists into our seaside town. The Captain Cook Memorial Museum has been filled with interested people looking to learn more about the explorer.

The museum had a massive 25,169 visitors come through the doors wanting to learn more about Captain Cook and his voyages. If you’re interested in paying them a visit yourself, throughout November they’re open Tuesdays and Saturdays 11am – 5pm. Can’t make those times? Then book yourself a private tour! The museum will then reopen in February 2019.

Find out more about Captain Cook in our Cook resources.

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