Q&A with Steve Skladanek, president of Lockheed Martin Commercial Launch Services

United Launch Alliance early Thursday delayed the launch of a triple-core Delta 4-Heavy rocket — the largest launcher in the company’s fleet — until Saturday to allow engineers more time to resolve an issue with a ground pneumatics control system.

A nuclear blast detection satellite and an assortment of experiments will be boosted directly into geosynchronous orbit 22,300 miles above Earth in 2019 by the most-powerful version of United Launch Alliance’s Atlas 5 rocket, the Air Force has decided.

Loaded with investigations into chemotherapy drugs with reduced side effects and radiation detectors for homeland security, a plant-growing chamber to promote future food harvesting in space and a technology demonstration for sample-return capsules, a commercial Cygnus cargo vessel will be sent to the International Space Station next week.