Live coverage: Atlas 5 countdown and launch journal

Fans of classical mythology and the fictional Star Trek universe can vote for two new candidates as the name of United Launch Alliance’s next generation rocket, with Vulcan and Zeus joining three other options in an online poll revealed earlier this week.

NASA managers Thursday cleared the $1.5 billion Parker Solar Probe for launch early Saturday on a daring mission to “touch the sun,” repeatedly flying through its outer atmosphere to find out why the blazing corona is millions of degrees hotter than our star’s visible surface.

An Orbital ATK Minotaur 4 rocket partially powered by modified motors from a Cold War-era nuclear missile lifted off early Saturday from Cape Canaveral with a small U.S. military satellite to help track other objects in space. The solid-fueled launcher took off at 2:04 a.m. EDT (0604 GMT) after a weather delay.