CONCORD, N.C. (AP) — NASCAR star Dale Earnhardt Jr., who missed the final 18 races of last season because of a concussion, has been medically cleared to return next year. Hendrick Motorsports announced Thursday that Earnhardt will take part in the season-opening Daytona 500 on Feb. 26. Dr. Micky Collins, medical director of the UPMC Sports Medicine Concussion Program in Pittsburgh, in consultation with Charlotte neurosurgeon Dr. Jerry Petty, cleared the 42-year-old driver Wednesday following a test session at Darlington Raceway in South Carolina.