December 21 not only marks the Winter Solstice for the northern hemisphere, but also the Great Conjunction of Jupiter and Saturn. As such, the search engine and tech giant Google has created a fitting doodle for its homepage. By going to Google.co.uk, a brief animation appears of Saturn passing by Jupiter, with the two planets taking the place of the Os in Google.
The other letters are covered in snow, representing the Winter Solstice.
Describing the doodle, Google said: “As Earth’s Northern Hemisphere hunkers down for winter and its longest night of the year, it seems Jupiter and Saturn have decided to put on quite an unusual show for the world to see!
“The two largest planets in our solar system will nearly overlap to form a ‘double planet,’ an event that hasn’t been easily visible since the Middle Ages – almost 800 years ago.
“Today’s animated Doodle celebrates the Northern Hemisphere’s first day of winter as well as this rare double planet sighting – or ‘Great Conjunction’ – which can be viewed from anywhere around the globe!”
The Winter Solstice marks the shortest day and the longest night of the year when the Sun is at its lowest in the sky.
The annual phenomenon is caused by the Earth’s North Pole tilting farther away from the Sun than at any other point in the year.
The Solstice also marks the official first day of winter, in astronomical terms at least.
There is no definitive start to winter, but astronomers will tell you it starts at the Winter Solstice, while meteorologists argue it begins on December 1.
“Meteorological winter starts on December 1 and includes December, January, and February.”
Jupiter and Saturn’s Great Conjunction happens every 20 years, but this is the closest they have been in over 400 years.
However, in that instance, the Great Conjunction occurred in the daytime, from Earth’s perspective’ meaning it was not visible.
You have to go back 800 years for the last time the two planets were so close and visible in the night time.