Astronomers gather to witness a sunrise transit of Mercury
It’s not very often that history repeats itself, allowing us to revisit events of the past and reflect on our history in a new light. However, thanks to a beautiful cosmic resonance between Earth, Mercury and the Sun, on 12 November 2019, and again on 10 November 2269, that’s precisely what is going to happen.
Almost exactly 250 years to the day after Charles Green, an astronomer who arrived in Aotearoa on Captain Cook’s first voyage pointed a telescope skywards to observe a rare transit of Mercury, the innermost planet will once again cross the bright solar disk as seen from Aotearoa.
To commemorate the event, and to share our nation’s rich bicultural astronomical heritage, the Otago Museum has organised a nationwide tour of expert astronomers. The week-long tour culminates with an all-night star party on Cooks Beach in Whitianga on the night of 11/12 November, the highlight of which will be observing the tiny disk of Mercury crossing the sun at dawn.
A planetary transit is when a planet moves between the Earth and the Sun, making its silhouette visible on the Sun’s disc. This transit happens approximately 13 times a century, but there is a lovely echo with it occurring almost exactly 250 and again 500 years to the day after Cook and the Endeavour crew viewed it when they arrived here.
Organised by Otago Museum’s Mercury Rising project Te Mahutatanga o Takero, and funded by Tuia250, the events will share the deep astronomical mātauranga of Māori, alongside the modern understanding of astrophysics. The project was created and driven by Ian Griffin, celestial photographer, Aurora chaser, and Otago Museum Director.
“It is such a great opportunity to showcase the rich bicultural tradition of astronomy in New Zealand, as well as present the cutting-edge science that is happening right now from our shores”, said Dr Griffin. “We have some of the leading astronomers in New Zealand and the world sharing their knowledge, and it will be amazing to get Aotearoa excited about the night sky.”
There will be free public talks in Dunedin on 5 November, Christchurch on 6 November, Wellington on 7 November, Auckland on 8 November, and Whitianga on 9 November. Four expert speakers will showcase their knowledge in all the centres.
Professor Emma Bunce is an internationally prominent astrophysicist and Professor of Planetary Plasma Physics at the University of Leicester. She is the President of the Royal Astronomy Society in the UK, and is principal investigator of the BepiColombo, a joint mission to the planet Mercury.
Dr Nick Rattenbury is a Senior Lecturer of Physics at the University of Auckland, and will be speaking about his world-leading research on extra-solar planets through gravitational microlensing.
Associate Professor Karen Pollard, who is the director of the Mount John Observatory – New Zealand’s largest telescope – will be discussing her research surrounding the evolution of stars and Matariki.
Ockie Simmonds, Treasurer of the Society of Māori Astronomy Research and Traditions, and an expert in Maramataka (the Māori lunar calendar), will be sharing new historical material and his love of the stars.
These talks culminate in the 11 November All Night Star Party in Mercury Bay, before the early morning transit of Mercury on 12 November. This free event is open to the public and will be held at the Reserve in Cooks Beach, starting from sunset at 8pm. The Otago Museum team, and both the Mercury Bay and Auckland Astronomical Societies will be there, showing the public how to use professional grade telescopes. The telescopes will be set up with equipment to hold mobile phones in order to capture images of the stars and planets that become visible.
Otago Museum’s Lab in a Box will be onsite with space-themed explorations running, where you can find out what stars are made of, and watch water rockets get propelled into the night sky. The event will continue throughout the night until sunrise at 6am. The transit will be in progress by then, and solar telescopes will be available for people to use, and take pictures with, until the end of the transit at 7am.
Of course, if it is overcast, the transit will be obscured, so two of the Otago Museum team will be flying above the clouds at the time of the passing to obtain images and videos.
All events are
open to the public – come for science, star-gazing, and