A SpaceX Falcon 9 rocket launches on its 11th mission, a record for a single booster, carrying 52 Starlink internet satellites into orbit from Vandenberg Space Force Base in California on Dec. 18, 2021.
Saturday’s early morning liftoff is one for the record books as it marks the 29th Falcon 9 mission for SpaceX so far in 2021, further solidifying a new company record for the most number of rocket launches in a year.
Saturday’s flight continues SpaceX’s efforts to expand and upgrade its burgeoning Starlink internet constellation. This is the fourth flight to carry its newly upgraded Starlink internet satellites, as the company recently equipped each of the flat-paneled satellites with the ability to communicate with each other via laser links. This will increase efficiency and reduce the constellation’s reliance on ground stations down here on Earth, company officials have said.
This launch brings the total number of Starlink satellites launched up to 1,944 since May 2019. It also has an unusual orbit, which will hug the coast of California as the satellites are eventually expected to reach a parking spot that’s a bit more centralized.
SpaceX has five orbital shells designed to be filled with roughly 4,400 Starlink internet satellites. These shells will be located at various altitudes above the planet, between 335 and 348 miles (540 and 560 kilometers) and at inclinations of 53, 53.2, 70, and 97.6 degrees.
To date, the 53-degree shell has been filled and SpaceX is turning its sights to other inclinations. Of the recent Starlink missions to launch, two payloads have been deposited into the 53.2-degree inclination and one into the 70-degree slot. That launch blasted off from California in Sept.
SpaceX aims to use its Starlink megaconstellation to connect people around the globe to the internet, particularly those in rural and remote areas who have little-to-no connectivity. Company officials have said that the program now serves more than 100,000 subscribers in 20 countries and is still growing.
SpaceX landed its first booster in 2015 and has been refining its reusability tactics ever since in an effort to streamline processes, get more use out of its boosters and further reduce costs. To that end, in 2018, the company introduced the version of Falcon 9 that we see flying today: the Block 5. This souped-up version featured a more robust thermal protection system, titanium grid fins, and a more durable interstage. These enhancements led to the rapid reusability SpaceX sees today.
The rocket featured in Saturday’s mission is one of the oldest in SpaceX’s fleet. Dubbed B1051 by SpaceX, the booster is now the most flown rocket, with 11 launches and landings under its belt. Its counterpart, B1049, is the only other rocket with 10 flights.
B1051 was first introduced in March 2019 as part of Demo-1 mission, which launched SpaceX’s first Crew Dragon spacecraft to the International Space Station as part of an uncrewed demonstration mission for NASA.
The Falcon 9 booster has also carried a trio of Earth-observing satellites for Canada, a broadband satellite for Sirius XM, and — as of Saturday’s mission — eight Starlink satellite groups.
When the Block 5 Falcon debuted in 2018, SpaceX founder and CEO Elon Musk speculated that each Falcon 9 would be capable of flying 10 times with very few refurbishments in between flights and as many as 100 times before retirement. As the company has recovered and reflown more rockets, SpaceX engineers are using that 10-flight threshold as just a guideline; as each Falcon 9 may be capable of many more flights.
In April, Musk said that the company would continue to push Falcon 9 to its limits to see how many flights and how much performance the company can get out of each rocket before any kind of major refurbishments are required. SpaceX will be using its own payloads like Starlink to do that.