NASCAR's most popular driver will hang up his helmet at the end of this season. Dale Earnhardt Jr. on Tuesday announced plans to retire after 18 seasons in the sport.
The announcement from Hendrick Motorsports follows a year of soul searching by the 42-year old race car driver. He missed half of last season after the latest in a series of concussions suffered on the track. He recently married longtime girlfriend Amy Reimann.

In an interview on NPR's Weekend Edition Sunday April 9, Earnhardt talked about how his life has changed since his last concussion.
"I certainly am more aware, whether I want to be or not, of how dangerous it is," said Earnhardt, whose father Dale Earnhardt Sr. died in a racing crash. "But going through the injury yourself really puts it into perspective of what's important."
Earnhardt is one of the sport's most popular and highest paid drivers. For the past 14 years fans have picked him as their favorite - the longest streak of any driver.
Two years ago, he also earned more than anyone else in NASCAR from prize money, endorsements and merchandise sales. His half-season last year saw him slip to second (behind Jimmie Johnson), with $21.1 million total, in an annual ranking compiled by Forbes.
Earnhard has started 600 races, and won 26, including two Daytona 500s.
He'll talk about the decision at a press conference this afternoon at 3.