5th July 1687 The book Principia is published by Sir Isaac Newton. Written in Latin with the title Philosophiæ Naturalis Principia...

For the month of May, 2019, though solar activity was once again was still very low, a few Sunspot groups did appear. A total of 24...

The long and short of it….. the orbital period of comets can range from long period comets like Comet McNaught, 92,700 years, to Comet...

13th June 1983 Pioneer 10 becomes the first human-made object to pass outside Pluto's orbit and leave the solar system. It was the...

This month we feature the Royal Greenwich Observatory and the Prime Meridian – Where East meets West The Prime Meridian is arbitrary and...

At last...there was a bit more solar activity in April as reported by Monty Leventhal OAM from his balcony in Maroubra, a suburb of...

2nd May 1780 Sir William Herschel discovers the first binary star, Xi Ursae Majoris, also named Alula Australis, in the constellation of...

Sara Cabrera is a Sydney City Skywatcher member and an active observer. Her curiousity to always learn more about astronomy took her...

This month ……. Telescopes. From the Greek “tele” meaning far, and “skopein” meaning to look or see Telescopes aren’t just for...

15th April 1970 Humans travel the furthest in space when the Apollo 13 crew reach 400,171 km from Earth in an attempt to return to Earth...