Saturday's mission marked the first time a Falcon 9 booster flew for a total of 12 flights, bringing the total number of Starlink satellites launched to more than 2,300.

For the Starlink Group 4-12 mission, SpaceX used a Falcon 9 rocket to launch 53 satellites into Low Earth Orbit. As scheduled, liftoff from Florida's Cape Canaveral Space Force Station's Space Launch Complex 40 (SLC-40) occurred Saturday morning at 12:42 EDT (04:42 UTC) (04:42 UTC).

According to Nasa SpaceFlight.com, for the first time, Saturday's mission marked the first time a Falcon 9 booster flew for a total of 12 flights, bringing the total number of Starlink satellites launched to more than 2,300.

When SpaceX launched the first Starlink Shell 4, they took a northeasterly path. This was the first time they took that path again. For a long time, SpaceX had been taking a southeasterly route with a "dogleg" around the Bahamas. Starlink Group 4-5 was launched in January. This was done to avoid bad weather in the North Atlantic Ocean during the winter. With spring on the way, SpaceX is now going to launch Starlink missions to the northeast again.

Just another Starlink mission, but SpaceX has confirmed that it will also set a new record for Falcon 9 reuse with this mission. When it comes to SpaceX launches, minor records are common, but this one stands out: booster B1051 has become the first Falcon 9 first stage to complete 12 orbital-class launches and landings.

B1051, the second-oldest operational Falcon 9 booster, made its debut on March 2nd, 2019 by supporting Demo-1, Crew Dragon's first unmanned test flight. The launch was flawless and launched both Crew Dragon and Falcon 9 B1051, both of which have a stellar track record. The B1051 has since launched the RADARSAT satellite constellation, SiriusXM's SXM-7 radio satellite, and 469 Starlink spacecraft over eight missions.

Starlink 4-12 is its 12th launch, just two weeks after its third anniversary, averaging one launch every three months or 93 days. B1051, an older booster and a fleet leader for several reusability milestones, has an average turnaround time between launches of about 100 days, but it has still accomplished a lot.

SpaceX CEO Elon Musk says that Starlink 4-12 was also the heaviest payload ever launched by Falcon 9, weighing in at 16.25 metric tons or ~35,800 pounds.

On its eleventh flight, It's unclear how SpaceX was able to push the Falcon 9's performance envelope. Musk claimed in May 2019 that the Starlink V0.9 payload would be SpaceX's heaviest ever, but three years later he claims Starlink 4-12 set a new record of 16.25 metric tonnes. Its 53 Starlink V1.5 satellites would each weigh 307 kilograms (675.5 lb).

While B1051 has twelve flights, newer boosters like B1058 and B1060 have much faster average turnaround times. After B1051's 12th flight, one of the two is almost certain to replace it as SpaceX's new fleet leader, meaning either B1058 or B1060 will be the first to set new reusability records.