Rocket and satellite maker SpaceX on Thursday sued a U.S. labor board to block its case accusing the company of illegally firing employees who sent a letter to company executives calling CEO Elon Musk "a distraction and embarrassment." SpaceX in the lawsuit filed in Brownsville, Texas federal court claims the structure of the National Labor Relations Board(NLRB), which issued a complaint against the company on Wednesday, violates the U.S. Constitution. The NLRB alleges SpaceX violated federal la