The 200th Atlas-Centaur rocket, history some 52 years in the making, will blast off Tuesday from Cape Canaveral to deliver a U.S. Navy mobile communications satellite into orbit.

Two companies — U.S. aerospace giant Lockheed Martin and British start-up Orbex — seeking to carve out a share of the burgeoning small satellite launch market plan to fly their rockets from a remote site on the northern shore of Scotland, British government and industry officials announced Monday.

United Launch Alliance called off the launch of a Delta 2 rocket from California’s Central Coast early Tuesday after boats ventured into a restricted safety exclusion zone and engineers ran out of time to resolve a technical problem on the launcher.