Jackie Robinson is one of the greatest baseball players in history, there's no doubt about it. His accomplishments are amazing and he changed the face of sports. He's soon well-known in baseball history and there's been plenty of dedications to him throughout the years; everything from statues to medals to ball parks have honored him. With astronauts now wearing his uniform into space, it proves how great he truly is.
Wearing the uniform of a player to honor them does not make them one of the greatest players ever. It makes you a fan of that player and the team they were on. What make someone one of the greatest players ever it the record they leave, how well they played the game and the impact they made on said game.
Astronauts certainly provide high honor to pioneering African American baseball player Jackie Robinson by wearing his uniform in space, but they could choose to honor those like Ellison Onizuka, the first Japanese-American astronaut and one of those killed in the Challenger disaster. A more appropriate tribute to Robinson would be if the entire Los Angeles Dodgers team decided to wear his jersey.
Jackie Robinson was an amazing baseball player but nobody is wearing his jersey and his number isn't retired by the entire MLB because he was really good. He is the icon that he is because he broke the color barrier. Even if he wasn't very good he would be remembered as the first black player in professional sports.