Stargazers and space fans will be treated to the peak of the annual Geminid meteor shower this week, with a New Moon affording a prime opportunity to spot a shooting star.
The Geminids are a regular sight for amateur astronomers at the end of each year, thanks to the Earth’s transit through the remnants of the asteroid 3200 Phaethon.
Phaethon is an unusual asteroid. It behaves a little bit like a comet – brightening and developing a ‘tail’ as it approaches the Sun (asteroids don’t do this), and its orbit is also comet-like. Passing through the debris of the object results in nightly meteor showers from early to mid-December.
The 5.1km wide object has been dubbed a ‘rock comet’, and might be the remnants of a dead comet, according to researchers. Earlier in 2023, scientists from the California Institute of Technology discovered that the little tail emitted by Phaethon isn’t dust or ice (as would be the case with a normal comet) but rather sodium gas.
While space researchers continue their studies into this unusual object, Earthlings can still kick back and enjoy the mysterious meteor showers it produces.
As the Earth passes through the debris field, tiny asteroid fragments – each about the size of a sand grain – hit the atmosphere at speeds over 127,000km/h and burn up, appearing as fast streaks in the sky.
The expected peak, depending on where you are on Earth, will come somewhere around 7:30pm (GMT/UTC) on Thursday 14 December, so viewing in Australia will be ideal in Australia in the early hours of Friday 15.
“When the Geminids reach their peak at around 2am AEST, you could see up to 40 or 50 every hour,” says Professor Jonti Horner, an astrophysicist at the University of Southern Queensland.
Best viewing times for the Geminids in Australia (all times local)
Sydney: 2.52am
Melbourne: 3.20am
Brisbane: 1:48am
Perth: 2.13am
Adelaide: 3:12am
Canberra: 3:00am
Hobart: 3:10am
Darwin: 2:42am
How to watch the Geminids
You won’t need binoculars or a telescope, but time and place are everything when it comes to prime viewing of a meteor shower.
And while the early morning on the 15th will be the best viewing for Australians, you’ll still be able to see them in more civilised hours of the night.
One thing that could make or break your experience, however, is light.
Fortunately, the Geminids’ peak this year coincides with a New Moon, so natural light pollution will be low, affording a relatively clear sky.
But with ever increasing light pollution in cities, people living in urban centres might want to find a darker location on the outskirts of the city to have an optimum view of the sky.
Key points
- The Geminid meteor shower happens every December as Earth passes through the debris of the asteroid 3200 Phaethon.
- The best viewing time will be when the constellation Gemini is due north from your viewing position. You can use a star chart app to find out when this will occur.
- Best viewing for Australians will be on the morning of December 15.
While Australians enjoying summer might not need to worry too much about clothing, people in the northern hemisphere might also want to rug up.
Last, but not least, your own eyes will need to adjust to looking at the sky.
“Go somewhere dark, away from bright sources of light, and make sure to spend at least half an hour under the stars to let your eyes adjust fully to the darkness,” Horner says.
“Just lie back and enjoy the meteors, and that time spent with your loved ones.”
