Photos: Delta 4 lights up the sky for night owl launch

The launch of a NASA research satellite built to probe conditions along the boundary between Earth’s atmosphere and space has been tentatively rescheduled for no earlier than Wednesday, pending the conclusion of a review of unexpected data signatures discovered on the first stage of the mission’s air-launched Pegasus XL rocket.

The center section of SpaceX’s first Falcon Heavy rocket has been test-fired at the launch company’s test facility in Central Texas, a sign of progress toward the behemoth booster’s long-delayed maiden mission scheduled some time in the final months of 2017.

A Soyuz booster and Fregat upper stage successfully carried a missile warning satellite into orbit Friday for the Russian military.