Extract from ABC News
In short:
The Bureau of Meteorology (BOM) forecasts significant geomagnetic activity over the next couple of days, which could result in displays of aurora australis in the night-time.
The geomagnetic storm was expected to be at its strongest on Tuesday evening.
What's next?
Aurora activity could continue for several days as the Sun emits a series of coronal mass expulsions.
It was only a few months ago that a dazzling show of technicolour auroras lit up the night sky and amazed viewers in Australia and around the world as a result of the largest geomagnetic storm in decades.
The stunning weather event, known as aurora australis in the southern hemisphere, has now returned to Australian skies.
The Bureau of Meteorology (BOM) released an aurora watch notice early on Monday morning, forecasting significant geomagnetic activity that could possibly result in visible auroras during night-time.
The geomagnetic storm was expected to be at its strongest on Tuesday evening.
BOM forecast a sequence of large expulsions of plasma and magnetic field from the Sun's corona, known as coronal mass expulsions, over the next couple of days.
When these forces hit the Earth's magnetic field, some of the particles can travel down the magnetic field lines near the north and south poles.
The captivating displays of pink, red, green and sometimes even violet, known as auroras, are created when the particles collide with gases in Earth's atmosphere.
BOM said an aurora alert would follow "if significant geomagnetic activity actually occurs", so a light show was not guaranteed, but enthusiastic aurora spotters have already been rewarded for keeping their eyes on the sky.
In May, stargazers around the world were treated to stunning displays of aurora australis in the south and aurora borealis in the northern hemisphere.
The southern display was not expected to be as strong as the one in May, which was the result of one of the strongest geomagnetic storms in two decades.
Geomagnetic storms are rated on what's known as the G-scale, ranging from G1 (minor) to G5 (extreme), according to BOM. The storm in May was rated as a G5.
The current forecast for Australia is G2 (moderate) from July 30 to August 1.
ABC
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