Los Angeles Marathon

March 21: The 25th Honda L.A. Marathon will begin outside the centerfield fence at Dodger Stadium at 7:20 a.m. Among the estimated 25,000 participants will be former Marine Cpl. Mervin Roxas, who lost his left arm and suffered injuries to his face in an IED attack in Iraq. He will run on behalf of the United States Veterans Initiative.

Iran power station on line

March 21: If Reuters reports are accurate, Iran will exacerbate a foreign policy headache for President Barack Obama. The news agency reports that Iran plans to begin operating its nuclear power plant today to coincide with the Iranian New Year. The United States believes Iran's forays into nuclear energy are a cover for trying to enrich uranium for use in nuclear bombs. Obama has called on the United Nations Security Council to impose further sanctions on Iran to discourage the nation's nuclear program.

Water Day

March 22: On World Water Day, environmentalists try to convince people of the importance of water conservation. The website H20Conserve.org estimates the average American's daily water footprint at 1,100 gallons per day. But that number isn't about flushing toilets; it's more about the gallons of water it takes to grow your food, power your car, and heat your home.

GOP preview

March 25: Two possible GOP presidential hopefuls are heading to key primary states for appearances in March. Minnesota Gov. Tim Pawlenty will keynote the Manchester Republican Committee Lincoln-Reagan Day Dinner in New Hampshire. Just four days later, former Massachusetts Gov. Mitt Romney will deliver a speech at Iowa State University in Ames. New Hampshire and Iowa are the traditional first two state battles during nomination season.

Census Day

April 1: The U.S. Census Bureau declared April 1 as Census Day as a reminder for all citizens to return census packets in the mail. Those who return forms will avoid a visit from census workers over the summer.

Pony Express' Sesquicentennial

April 3: The United States Postal Service will celebrate the 150th anniversary of the Pony Express, the horse-powered quick mail delivery service that transported messages from St. Joseph, Mo., to Sacramento, Calif., beginning on April 3, 1860. Despite its ­short-lived career-just 19 months ended abruptly by the telegraph-the Pony Express stuck in American folklore. At its fastest, the team of riders could deliver a message to far-away California in just 10 days.