After a long holiday weekend, shares of U.S. space stocks took off like rockets on Tuesday. As of 1:20 p.m. ET, AST SpaceMobile ( ASTS 3.59% ) had gained 6.3% and seemed poised to resume its winning streak. Rocket Lab USA ( RKLB 4.75% ) wasn't far behind, up 5.6% after announcing a successful weekend rocket launch.