Yes, tis the day of the Summer Solstice, which occurred at 0447 this am.
This is when the Sun is at its most southerly position for the year, and is the longest day of the year for those in the Southern Hemisphere.
http://museumvictoria.com.au/discove...d-the-seasons/
Must be an excuse for a celebratory champagne
... ah, or a beer.