Falcon 9 scrubs in wake of Falcon Heavy delay

A Falcon 9 stands ready for launch with 23 Starlink satellites on pad 40. Image: Adam Bernstein/Spaceflight Now.

SpaceX scrubbed the launch of a Falcon 9 rocket after delaying a Falcon Heavy launch for the U.S. military. It had planned the launch Monday night, less than three hours after the scheduled launch of a Falcon Heavy from nearby pad 39A. Liftoff of the Falcon 9 with 23 Starlink satellites was tentatively rescheduled for 11:02 p.m. EST (0402 UTC) Tuesday.

If the doubleheader with the Falcon Heavy goes off om Tuesday it would be the shortest interval between orbital launches from Cape Canaveral since the Gemini program in the 1960s. With the Falcon Heavy scheduled for launch no earlier than at 8:14 p.m. EST on Tuesday, the Falcon 9 would follow two hours and 48 minutes later.

U.S. Space Force meteorologists at the 45th Weather Squadron said Sunday there was an 60-percent chance of acceptable weather for the Falcon 9 launch on Wednesday, with liftoff winds and thick clouds being the concerns.

Spaceflight Now’s live coverage of the launch will get underway about an hour before liftoff. You can also watch 24-7 views of launch pads at the Cape in our Launch Pad Live stream.

The Falcon 9 booster for Tuesday’s Starlink 6-34 mission, tail number B1081, is making its third flight. It previously flew two missions for NASA, one carrying Dragon Endurance in August with a four-member crew to the International Space Station and the other being a Cargo Dragon on a space station resupply mission 32 days ago in November.

After lifting off from pad 40 at Cape Canaveral, the Falcon 9 will head south-easterly targeting an orbit inclined 43 degrees to the Equator. It’s nine Merlin 1D engines will fire for nearly two and a half minutes before the first stage separates from the second stage. The first-stage booster will continue downrange to land on the drone ship ‘A Shortfall of Gravitas’ in the Atlantic Ocean, east of the Bahamas.

The rocket’s payload fairing halves will land on parachutes a little further downrange from the drone ship and be scooped up by the support ship ‘Bob’, named after Crew Dragon Demo-2 astronaut Bob Behnken.

Meanwhile the single vacuum Merlin engine of the second stage will fire for about six-minutes to reach a parking orbit. After coasting for about 45 minutes, the second-stage engine will re-ignite for a three-second burn to refine the orbit. Deployment of the 23 V2 Mini Starlink satellites will follow at about one hour and five minutes after launch.