NEWPORT NEWS, Virginia — Walking into a control station at Jefferson Labs, Quentin Saulter started horsing around with his colleague, Carlos Hernandez. Saulter had spent the morning showing two reporters his baby: the laboratory version of the Navy’s death ray of the future, known as the free-electron laser, or FEL. He asked Hernandez, the head of injector- and electron-gun systems for the project, to power a mock-up electron gun — the pressure-pumping heart of this energy weapon — to 500 kilovolts. No one has ever cranked the gun that high before.

Smiling through his glasses and goatee,...

When a couple dozen companies sign contracts containing the words “moon” and “landing,” it’s a good indication that private lunar exploration is heating up.

The X Prize Foundation on Thursday announced that 29 teams had signed contracts making them the official Google Lunar X Prize competitors, contending for more than $30 million in prizes. The competitors, headquartered in 17 different countries, have been crafting promising business plans and rolling out prototypes. One team, Astrobotic Technology, has even arranged its rocket ride to the moon already.

“We could be intimidated by that d...