March 20 marks the Northern Hemisphere's vernal equinox, the day when the hours of daylight are equal to the hours of darkness. It's also the first day of spring.
Google kicked off the new season by transforming its homepage logo into a tribute to the rebirth that springtime offers. Replacing the letters in the iconic company logo are flowers, critters and a truck transporting landscaping shrubbery.
The doodle was inspired by Finnish textile design house Marimekko, the Google Doodle team told the Washington Post. Indeed, the Post points out that the doodle's blue flower (which appears in place of the "G" in "Google") and colorful critters (in place of the second "O" and the "E") look to be directly influenced by Marimekko prints.
The U.S. Naval Observatory lays out the astronomical characteristics that make the equinox unique among days of the year:
On the day of an equinox, the geometric center of the Sun's disk crosses the equator, and this point is above the horizon for 12 hours everywhere on the Earth. However, the Sun is not simply a geometric point. Sunrise is defined as the instant when the leading edge of the Sun's disk becomes visible on the horizon, whereas sunset is the instant when the trailing edge of the disk disappears below the horizon. These are the moments of first and last direct sunlight. At these times the center of the disk is below the horizon. Furthermore, atmospheric refraction causes the Sun's disk to appear higher in the sky than it would if the Earth had no atmosphere.
The vernal equinox is usually observed with festivities around the world each year. According to The Guardian, "The date is particularly significant for pagans, many of whom carry out rituals, while others indulge in activities such as egg races, egg hunts and egg eating and egg painting. A number of Spring harvest festivals are celebrated at this time while Vernal Equinox Day is a national holiday in Japan, when families visit graves and hold reunions."
Take a look at the Marimekko-insprired doodle (below).
Check out the slideshow to see some of our favorite Google Doodles ever.