The couple developed this field from research in South and South-East Asia, particularly India, Indonesia and the Philipines and have been working on applying it to Māori culture.
Orchiston said the astronomy of early Māori settling in New Zealand was different to the astronomy of Māori from when James Cook first arrived in New Zealand.
This was because astronomy and ecology, the environment people live in and the food they eat, are linked.
“The relationship you have between yourselves as individuals and the landscape... all of that is reflected in astronomy.”
The food a group of people catch or grow to eat often becomes part of what they see when they look up at the stars, he said.
An example of this he gave was the star cluster Matariki, which a forest tribe in India instead associated with a species of small birds they hunt.
“Not only that, they developed a special kind of net to catch these birds... that nets in the sky and it’s there adjacent to where the birds are,” he said.
The couple were furthering their research on ethnoastronomy in relation to Māori and the differences between astronomies across different iwi while on tour through the country.
They were also conducting research on a book on the history of astronomy in New Zealand, having previously written an 800-page book on the topic which Orchiston said was only half the story.
For this, they were excited to be in Whanganui due to the archives the Whanganui Astronomical Society had on record and the historic nature of the Ward Observatory and its telescope.
“It’s an internationally famous telescope, we’ve given papers about this at international conferences, it’s not just significant for New Zealand.”
The telescope, originally built in England, was the first to have an English Equatorial Mounting made out of metal rather than wood, which stopped it from flexing over time.
The Astronomical Society had also archived letters between the founder of the observatory, Joseph Thomas Ward and other local leading astronomers of the time, which the couple would be looking over.
He said on previous lectures people found the relationship between how people perceived the land and the skies to be interesting, having not known about ethnoastronomy.
The lecture will be held at the observatory on St Hill St at 7pm on Wednesday, June 21, with all welcome and entry via koha.
The telescope will also be opened after the talk if the weather was co-operative.