Watch the Parker Solar Probe pre-launch mission briefing

A SpaceX Falcon 9 rocket fired through a dense shroud of coastal fog and climbed into orbit Wednesday from Vandenberg Air Force Base in California, deploying a trio of radar observation satellites to begin a $900 million mission surveying the Arctic, maritime waters, forests and farmland for the Canadian government.

Technicians began the painstaking work of assembling a powerful Atlas 5 rocket today, a launcher that will deploy an advanced satellite to substantially improve U.S. weather forecasting.

A United Launch Alliance Delta 2 rocket fired away from a California military base and disappeared into an overcast cloud deck Saturday on its final flight, carrying a NASA research satellite into orbit and closing the book on a nearly 30-year legacy of launches.