Photos: Tuesday’s Atlas 5 rollout

Failure struck Russia’s troubled space program for the second time in three weeks Saturday, when a Proton rocket carrying a high-tech satellite for Mexico’s new $1.6 billion space-based communications network crashed shortly after liftoff.

Launching for the 50th time, an Atlas 5 rocket flew a milestone mission Wednesday in deploying a Global Positioning System satellite for the worldwide utility.

The launch of a Boeing-built Mexican communications satellite on a Proton rocket has been postponed after engineers discovered an anomaly on a similar spacecraft.