A NASA mission that will come closer to the sun than ever before is officially underway.
The Parker Solar Probe was launched atop a United Launch Alliance Delta Four Heavy rocket Sunday from Cape Canaveral on Florida's Space Coast at 3:31 a.m. Eastern time.
Liftoff had been scheduled for Saturday morning, but the countdown was halted at the last minute by a helium pressure issue.
The Parker Solar Probe is designed to fly through the sun's super-hot corona to study the solar wind and sun storms.