This Friday, April 29, the space shuttle Endeavour blasts off for the last time, in its 25th and final mission.

Endeavour was the fifth and final space shuttle to be built, and the launch on Friday will be the penultimate space shuttle flight. Space shuttle Atlantis, due to take off on June 28, 2011, will be the final mission before the space shuttle program is officially retired after 30 years of service.

And thanks to a special giveaway on Twitter by @NASA, 150 lucky Twitter fans have bagged a once-in-a-lifetime prize.

Read more