AUSSIE SKY-WATCHERS WILL HAVE THEIR GAZE fixed firmly on the sky this weekend, as one of the best meteor showers of the year puts on a display.
The Eta Aquariids shower will be best seen in the early morning hours, between about 3:30am and sunrise.
“The Eta Aquariids is one of the year’s best meteor showers for the Southern Hemisphere, partly because it is such a consistent shower, regularly producing bright meteors in the early morning for about a week, and also because it is well placed in our sky,” says Dr Tanya Hill, astronomer at the Melbourne Planetarium.
A meteor shower occurs when Earth passes through a clump of dust, or meteoroid stream, that’s orbiting the Sun. For the Eta Aquariids, the dust has been left behind by Comet Halley.
It takes about six weeks for Earth to cross completely through the stream, from mid-April through to late May. But we pass through the thickest part around May 5 to 8.
“The special thing about meteor showers is that all the meteors appear to come from the same part of the sky,” says Dr Hill, referring to what astronomers call the meteor shower’s ‘radiant’.
For the Eta Aquariids, the radiant is near the faint star Eta Aquarii, which at this time of the year rises in the east around 2:00am and is high in our northern sky by sunrise. (For our Northern Hemisphere readers, the radiant rises just a couple of hours before sunrise and remains much lower in the sky.)
“The higher the radiant in the sky, the more meteors can be seen,” says Dr Hill.
From a dark spot in a city location, you can expect to see perhaps one meteor every 5 or 6 minutes. From a dark country spot, perhaps one every 3 minutes.
You don’t need to have a telescope or binoculars. Just your own eyes is all you require.
Here are Dr Hill’s top tips for getting the most out of the meteor shower:
- Get comfortable. You’ll need to spend a considerable amount of time under the stars to catch the meteors. For example, it takes at least 15 minutes for your eyes to start to become dark adapted and allow you to notice the fainter meteors. That also means you should dress warmly.
- Find somewhere dark. Choose an observing spot away from street lights and with a good view of the entire sky. And don’t just look in the one spot. “While the meteors appear to radiate from near Eta Aquarii, they can travel quite a way across the sky,” says Dr Hill. “You want to be looking about 30 to 45 degrees to the left or right of the radiant — choose the direction with the least light pollution.”
- Watch with a friend. “Meteor observing is much more fun with family and friends around,” says Dr Hill. “That way there’ll be lots of oohs and aahs to share.”