Editor’s Note: This story has been updated from a previous version.

SpaceX’s Falcon Heavy will likely launch on its first commercial flight today. The rocket launch was postponed from early April due to unspecified concerns, and then postponed again just this week due to weather. But Wednesday has a clear forecast with an 80 percent probability of a launch, so odds are good the mission will proceed. The launch window opens at 6:35 p.m. EDT this evening and extends until 8:32 p.m. EDT on T