Launch of the Curiosity Mars rover

A new fixture on the Cape Canaveral skyline began rising Tuesday with the placement of the first of seven segments for a 200-foot-tall crew access tower at the Atlas 5 rocket’s seaside launch pad for astronauts boarding Boeing’s new commercial CST-100 Starliner spaceship.

Watch a 4K video replay of the launch of a SpaceX Falcon 9 rocket and Cargo Dragon spacecraft Dec. 6 on a resupply mission to the International Space Station.

Arianespace has split its third order of Vega rockets from Italy’s Avio between old and new versions of the solid-fueled booster, as officials prepare to build a final batch of around 18 Ariane 5 rockets before switching to the next-generation Ariane 6 in the early 2020s.