AST SpaceMobile (NASDAQ:ASTS) stock is rocketing higher on Thursday after the space-based cellular broadband network company signed an agreement with wireless provider AT&T (NYSE:T).This agreement caps off a Memorandum of Understanding between the two companies that was signed in 2018. it has them working together on a space-based broadband network available to everyday cellphones through 2030.AST SpaceMobile plans to start this effort this summer with the delivery of five commercial satellites to Cape Carn ...