Greg Nicholl was fine tuning equipment on his telescope near La Perouse, in the south of Sydney, early this morning, June 23 2015, when he noticed a subtle pink glow on the southern horizon. Greg takes up the story...

Has it been dark lately when you arrive home from work or school? Have you noticed the nights are long and the days are cold? Its winter solstice time again! Solstice means "sun standstill", but the Sun's apparent motion doesn't stop nor does the Earth stop turning.

A Great Prominence Ejects, Sketch and copyright Harry Roberts ©, all rights reserved. Regular solar observer & correspondent Harry Roberts reports on the ejection of a large prominence from the Sun's limb.

This morning at 9:45am AEDT the Sun crossed from the southern to the northern part of the sky. On this day daytime and nighttime are almost equal at 12 hours each. Daytime though is a little longer than 12 hours due to the size of the Sun's disc and because the atmosphere bends the light from the Sun.

That’s right! Today is the day that we celebrate the mathematical constant π (Pi) – 3.141592653589793232384626433… But why is today Pi Day? Because… if you write the date in the MM/DD format, today is 03/14 and 3.14 are the first three digits of the irrational number that is the ratio of a circles circumference to its diameter.