Google today celebrates the 42nd birthday of ‘Earth Day 2012’ with a customary Google doodle. a day dedicated to creating awareness and promoting green economic policies around the world.

Google Doodle : Earth Day 2012

Google has replaced its logo with a time-lapse animation of blooming flowers to mark Earth Day, The doodle featured a time-lapse animation of blooming flowers in purple, red and yellow flowers sprout out from a series of shrubs laid out to spell the word Google.

The doodle is animated, but it’s not a GIF, rather Google used a simple JavaScript to hack a large JPG image and display only portions of it at a time, as frames.

Earth Day was first held on 1970 after Gaylord Nelson, a US senator, conceived it as a tool to promote an environmental agenda after witnessing a huge oil spill off the coast of California a year earlier.

Organisers claim the 1970 event rallied millions across the country as it tapped in to the rise of hippie culture and anti-Vietnam war protest movements. “Groups that had been fighting against oil spills, polluting factories and power plants, raw sewage, toxic dumps, pesticides, freeways, the loss of wilderness, and the extinction of wildlife suddenly realised they shared common values,” the official Earth Day website says.

This year’s Earth Day is centred around a scheme called “one billion acts of green”, which encourages individuals to make simple environmentally conscious pledges, such as switching off lightbulbs or reducing car journeys. Organisers say the day is now observed in 192 countries.