Scientists are asking all Australians to step outside on the longest night of the year to help measure light pollution across the country.
Australasian Dark Sky Alliance CEO and founder Marnie Ogg said they were expected thousands of people on Sunday, June 21, help researchers create a map of Australia's darkest skies.
They'd "also learn about light pollution and its effect on people, animals, and astronomy", Ms Ogg said.
"Together, our observations will map how light pollution varies across Australia's cities and regions, and make a Guinness World Records attempt for 'most users to take an online environmental sustainability lesson in 24 hours'."
ARC Centre of Excellence in All Sky Astrophysics in 3 Dimensions (ASTRO 3D) director, astronomer Professor Lisa Kewley, said the Australian night sky was amazing.
"Our galaxy, The Milky Way, is painted across the sky. It's a view that encourages us to wonder what's out there, amongst the billions of stars," Professor Kewley said.
"It's a view that encourages kids to take up science and physics. But most Australians can't see it, their view of the sky is blinded by light pollution."
But the downside was that light pollution didn't just disrupt the view of The Milky Way, Ms Ogg said.
"It disturbs wildlife, disrupt people's sleep, and represents wasted electricity," she said.
"The information will help councils plan for darker skies and create opportunities for tourism. Dark sky parks and tours are already popping up around the country."
The University of Melbourne wildlife ecologist Dr Jen Martin said further understanding of light pollution helped scientists understand its impact on wildlife.
"For example, light pollution from cities distracts bogong moths as they migrate from Queensland to Victoria's alpine regions. If they don't arrive on time, the endangered mountain pygmy possums that depend on them for food will starve."
The Guinness World Records attempt starts from 1pm AEST on Sunday June 21, 2020 and follows night fall around the world.
All the submissions will be added to the international database of Globe at Night and participants from across the planet are welcome to take part.
The project is supported by the Australian Government Department of Agriculture, Water and the Environment, which has produced The National Light Pollution Guidelines for Wildlife.
Other supporters include ASTRO 3D, AstroNZ, Bintel, ICRAR, Globe at Night, Unihedron, ANU, the International Dark Sky Alliance, Laing Simmons & Young, Waiheke Island Dark Sky Park and Dark Sky Traveller.
For more information and to register, visit https://worldrecordlight.thinkific.com/.