NASA's Parker Solar Probe is ready for a Saturday launch

NASA's Parker Solar Probe— the space agency's new spacecraft designed to "touch the sun" — is packed up, buckled in and ready to launch during a window opening Saturday (Aug. 11) at 3:33 a.m. EDT (0733 GMT) from NASA's Kennedy Space Center (KSC) in Florida, according to a NASA news conference today (Aug. 9).

The weather is the team's only lingering concern, agency staff said. Right now, there's a 70-percent chance that the weather will cooperate for a Saturday morning launch, Air Force weather officer Kathy Rice said during the news conference.

Given Florida summer weather patterns, the team is concerned about the potential of thunderstorms, although that risk is lower in the early-morning hours. Rice also said local personnel will monitor the risk that the launch itself could trigger lightning strikes.

The Parker Solar Probe as seen on July 16, 2018, waiting to launch aboard a United Launch Alliance Delta IV Heavy rocket. Credit: NASA/Johns Hopkins APL/Ed Whitman

Saturday's launch window will remain open for about 65 minutes, Omar Baez, launch director at KSC, said during the news conference. If the launch were to occur after that time, he and his colleagues are concerned that the spacecraft could potentially be damaged while flying through the Van Allen radiation beltsthat surround Earth.

A launch rehearsal conducted yesterday (Aug. 8) went smoothly, Baez said, and he will receive a final weather briefing tomorrow (Aug. 10) at about 10 p.m. EDT (0200 GMT on Aug. 11) to determine whether to fuel up the rocket in hopes of targeting Saturday morning's launch window.