WASHINGTON — NASA has selected the Delta 4 Heavy built by United Launch Alliance to launch its Solar Probe Plus mission in 2018, the agency announced March 18.

That launch, valued at $389 million, will also use a Star-48 upper-stage motor provided by Orbital ATK.

The choice of the Delta 4 Heavy is not surprising: Last year, NASA ruled out the use of the most powerful Atlas 5 because that would have required a new, custom-built upper stage.

NASA relies almost exclusively on the Atlas 5 to launch its scientific satellites, although a Delta 4 Heavy was used to launch the agency’s Orion deep-space capsule on an uncrewed test mission in December. That launch was procured commercially by Orion prime contractor Lockheed Martin Space Systems.


Warren Ferster is the Editor-in-Chief of SpaceNews and is responsible for all the news and editorial coverage in the weekly newspaper, the spacenews.com Web site and variety of specialty publications such as show dailies. He manages a staff of seven reporters...