Catching the aurora
10 October 2018
You do have to be pretty lucky to see an aurora, but if you do see one you won't be disappointed. Improve your chances with these tips from Bureau space weather expert Dr Jeanne Young.
The brightest auroras are concentrated in rings called the aurora ovals around the north or south poles. The auroras in the northern hemisphere are called aurora borealis; southern lights are called aurora australis (from the Latin word for southern). The aurora australis is best viewed from Antarctica, Tasmania and the southern coastlines of mainland Australia.
The colours displayed by an aurora are generally visible to the naked eye if you're near the poles, where the aurora is overhead and more intense. At lower latitudes, the auroras are on the horizon and less colour can be seen by the naked eye—the lights tend to appear to be shades of grey. If there is a very intense solar storm, though, you'll see more colour.
Auroras can occur at any time in the year, but they're most likely to occur during the months of March and September (around the equinoxes)—that's when the Earth's magnetic field is best oriented to interact with the solar wind.
You ideally need a dark night with little cloud cover. You don't want a bright moon or any light pollution, so a good location is a dark beach or a hill where you have an unobstructed view to the south. Bright auroras usually last for 1–3 hours and the best viewing time is around midnight—between 10 pm and 2 am. However, there's no magic hour that you're guaranteed to see auroras—keen aurora chasers usually keep an eye on our real-time geomagnetic indices (which show the level of geomagnetic activty) and stay up all night if need be!
The Bureau will issue an Aurora Watch notice at www.sws.bom.gov.au/Aurora when solar wind conditions look favourable for auroras occurring in the next 1–3 days. When there's a high chance that there will be an aurora visible now, we issue an Aurora Alert. You can also sign up to receive these Watches and Alerts by email or SMS at www.sws.bom.gov.au/Products_and_Services/4/1.
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