NASA is holding a tournament in which participants can vote for what they think are the all-time greatest missions out of 64.

The Mission Madness competition begins today.

Space fans will be able to view a lineup of 64 missions, learn about their goals, and predict which missions fellow exploration fans will vote for during this bracket-style, single elimination tournament.

The Mission Madness tournament provides key matchups between 16 past, present and future missions in each of four divisions — Nebula, Stellar, Galaxy and Horizon.

Round one features 32 predetermined matches. Visitors to the tournament Web site can learn about the missions chosen for the competition, print out a bracket and make predictions. Voting for round one begins March 19, and the first Mission Madness championship winner will be determined April 8.

Each round consists of two days of online voting. Fans will be able to vote for their favorite missions as many times as they like while polls are open. At the conclusion of each round, the winning missions advance in head-to-head competition, allowing fans to see how their predictions compare to those of other voters.

NASA EDGE, an unscripted, non-traditional video podcast team that highlights all things NASA in a unique and youthful way, created and developed the tournament in an effort to generate new and fresh discussion about NASA’s most historic, successful and inspiring missions.

NASA EDGE hosts Chris Giersch, Blair Allen, Franklin Fitzgerald and special guest Jacky Cortez will be joined by three Mission Madness analysts. Miles O’Brien, former CNN reporter, Melvin Ferebee of NASA’s Langley Research Center in Hampton, Va., and Keith Cowing of the blog NASA Watch, will provide their opinions about the how early rounds will develop and which missions will remain competitive deep into the tournament.

To be a part of NASA’s 2009 Mission Madness tournament, visit: http://www.nasa.gov/missionmadness on the Web.

To comment about the Mission Madness tournament, visit the NASA EDGE blog at: http://blogs.nasa.gov/nasaedge

To learn more about NASA EDGE, click on: http://www.nasa.gov/multimedia/podcasting/nasaedge