CAPE CANAVERAL, Fla. >> Space shuttle Discovery blasted off on its final voyage this afternoon.

Six astronauts are on board the world’s most traveled spaceship. They’re headed for the International Space Station after a four-month delay for fuel tank repairs.

This is Discovery’s 39th and final mission. It’s the first of the three space shuttles to be retired this year.

No other spacecraft has been launched more times.

Tens of thousands witnessed history in the making from the Florida launch site. Countless more watched from surrounding towns. Roads leading into Kennedy Space Center were jammed.

Discovery should reach the space station Saturday. It will deliver a compartment full of supplies as well as the first humanoid robot to fly in space.