Photos: Delta 4 powers from launch pad on military mission

Problems with a downrange tracking station kept Rocket Lab’s Electron launcher on the ground in New Zealand Friday, U.S. time, and the company ordered a two-day delay to resolve the issues and wait for improved weather. Rocket Lab pushed back the launch again to Tuesday because of unfavorable weather.

Astronauts Jeff Williams and Kate Rubins ventured outside the lab complex Friday for a long-awaited spacewalk to attach a new docking mechanism, the first of two that will be used by U.S. crew ferry ships being built by Boeing and SpaceX to carry astronauts to and from the outpost, ending NASA’s sole reliance on Russian Soyuz spacecraft.

NASA says it is interested in flying astronauts and scientists on commercial suborbital vehicles, like those being tested by Virgin Galactic and Blue Origin, to provide additional training and research opportunities augmenting missions to the orbiting International Space Station.