The California launch countdown ends with a SpaceX abort

A Falcon 9 launch from Vandenberg Space Force Base in California was aborted less than a minute before liftoff Thursday, SpaceX's first terminal countdown abort in more than 18 months.

As scheduled, SpaceX's Falcon 9 rocket was scheduled to launch for its Starlink 3-2 mission at 10:39 a.m. Thursday morning from Vandenberg Air Force Base, a military launch pad located 150 miles (225 kilometers) northwest of Los Angeles.

The pre-launch sequence was aborted by the countdown's computer sequencer at T-minus 46 seconds. It was not clear why SpaceX had put its launch on hold, but weather parameters and the military-run range at Vandenberg appeared to be 'go'.

During Thursday's launch opportunity, the company had two instantaneous launches to align with Starlink's orbital planes. The Falcon 9 rocket is awaiting the launch of 46 Starlink internet satellites from California.

As soon as the Falcon 9 rocket is loaded with propellants, SpaceX's launch team has limited options. Rockets use densified, super-chilled liquid oxygen and kerosene propellants, which can get hot if they remain on the ground for too long before taking off.

Rocket boosters are being drained of propellants in preparation for SpaceX's Falcon 9 launch on Friday. A second launch attempt is tentatively scheduled for Friday at the same time - 10:39 a.m. Pacific Time.

In December 2020, SpaceX stopped a countdown during the final phase of preparations for a launch from Florida for the National Reconnaissance Office due to a technical issue. SpaceX engineers encountered an unexpected pressure reading during that launch attempt, then horizontally lowered the rocket for troubleshooting, before successfully launching two days later.

As a result of bad weather or range violations by ships and aircraft diving into restricted airspace or waters near the launch site, SpaceX has scrubbed multiple Falcon 9 countdowns since December 2020. The Falcon 9 rocket or ground systems have caused a few launch delays, but none have occurred in the final countdown sequence.

More than 18 months after NROL-108 was scrubbed due to a technical issue, SpaceX has launched 62 Falcon 9 missions.

As the Falcon 9 rocket launches the next 46 satellites in California, it will become the 32nd mission in a calendar year, breaking the 2021 record of 31 missions.

We are barely halfway through the year, which means SpaceX will accomplish nearly twice as many launches as in 2021. SpaceX has launched more successful missions into orbit so far this year than the combined efforts of any other nation, and the company is far outpacing its chief competitors in the commercial marketplace.

United Launch Alliance has launched four rockets successfully this year in competition with ULA for military launch contracts. It has accomplished three missions so far in 2021 for Arianespace, the European commercial launch company.

As of January 31, SpaceX has delivered 351 metric tons (about 774,000 pounds) of payload mass into orbit. As a result of the flights, astronauts have been flown to the International Space Station, many small satellites have been launched for the Starlink network and customer fleets, and national security payloads have been deployed by the U.S. spy satellite agency.

Another Falcon 9 rocket with another batch of Starlink internet satellites is being prepared for launch at the Kennedy Space Center while SpaceX prepares for the launch of Starlink 3-2.