The vernal equinox: the first day of spring

People enjoy the first day of spring on the National Mall in Washington, D.C.   (Mark Wilson / Getty Images)

Donald Croteau works to clear nearly a foot of snow off his car on the first day of spring in North Woodstock, N.H. Much of the country remains in a deep freeze.  (Jim Cole / Associated Press)

Flowers bloom in Central Park in New York City on Thursday. Today marks the first official day of Spring - the spring equinox occurred at 12:57PM today.  (Andrew Burton / Getty Images)

Men play volleyball in Central Park in New York City on Tuesday. Today marks the first official day of Spring - the spring equinox occurred at 12:57PM today.  (Andrew Burton / Getty Images)

John Senden of Australia hits his tee shot on the 18th hole during the first round of the Arnold Palmer Invitational presented by MasterCard at the Bay Hill Club and Lodge in Orlando, Fla.  (Michael Cohen / Getty Images)

Spring de Haviland is overwhelmed by a wave while handing out carnations as part of the 3rd annual “Spring Into Kindness” day north of the Santa Monica Pier in celebration of the first day of Spring. She hopes to encourage everyone to support the group One Million Acts of Kindness whose goal is to encourage every one to perform one million acts of kindness in one’s lifetime. On the first day of Spring, participants are asked to surprise someone with an act of kindness. This is the third year that Spring de Haviland has participated in the campaign on the first day of Spring.   (Genaro Molina / Los Angeles Times)

A firefighter sets up a hose as he battles a fire in York, Pa. Firefighters said seven buildings were damaged, four of them heavily. No injuries were reported. The Red Cross was assisting 11 people forced from nearby row homes.   (Jason Plotkin / Associated Press)