A Falcon 9 rocket delivered 51 more Starlink internet satellites into orbit Friday after launching from Vandenberg Space Force Base in California, adding to SpaceX’s global broadband network that reaches all seven continents.
The Starlink 2-5 mission began with liftoff at 11:12:20 a.m. PST (2:12:20 p.m. EST; 1912:20 GMT) from Space Launch Complex 4-East at Vandenberg, a military spaceport about 140 miles (225 kilometers) northwest of Los Angeles. After a smooth 35-minute automated countdown, the 229-foot-tall Falcon 9 rocket fired its nine kerosene-fueled Merlin engines and climbed away from Vandenberg with 1.7 million pounds of thrust.
Soaring into a mostly sunny sky, the Falcon 9 flew on an arc downrange from Vandenberg, heading south-southeast over the Pacific Ocean to target an orbit inclined 70 degrees to the equator.
Two-and-a-half minutes into the mission, the Falcon 9’s first stage booster — tail number B1063 — shut down its nine engines and separated from the upper stage in the upper atmosphere. The upper stage lit its single engine for a six-minute firing to inject the flat-packed Starlink satellites into an elliptical transfer orbit.
The first stage, meanwhile, unfurled four titanium grid fins, or winglets, to help stabilize itself during re-entry back into the atmosphere. A braking burn with three of the booster’s engines slowed the rocket for re-entry back into the atmosphere, then a final burn with just the center engine allowed the 15-story-tall rocket to settle onto SpaceX’s drone ship “Of Course I Still Love You” parked in the Pacific off the coast of Baja California.
The landing completed the ninth flight to space for this booster, and the 172nd landing overall of a Falcon rocket.
Fifteen minutes into the flight, the Falcon 9’s upper stage released the 51 Starlink satellites — each weighing more than quarter-ton — to begin their mission beaming broadband, low-latency internet services to customers around the world.
The launch Friday from California was the first of two SpaceX missions on tap the same day. Later Friday night, SpaceX plans to launch a Falcon 9 rocket from Cape Canaveral with a high-power geostationary communications satellite for Inmarsat. That mission is set for liftoff at 10:59 p.m. EST (0359 GMT).
The launches will mark the 11th and 12th missions of the year for SpaceX.
The Starlink 2-5 mission Thursday aimed to deploy the 51 Starlink satellites into an orbit between 138 miles and 208 miles (222-by-335 kilometers) above Earth. The satellites will extend their solar arrays and switch on krypton-fueled ion thrusters to raise their orbits to an altitude of 354 miles (570 kilometers), where they will become part of Group 2 of the Starlink constellation.
SpaceX’s first-generation Starlink fleet is spread out into five groups, or orbital shells, between 335 miles and 354 miles in altitude. The first-generation Starlink shells are inclined at different angles to the equator, with some satellites orbiting between 53 degrees north and south latitude, and others in orbits flying from pole-to-pole.
SpaceX began launching satellites into its second-generation Starlink constellation, called Gen2, in December, but the Starlink 2-5 mission continued filling out the first-generation Starlink fleet. The 51 Starlink internet satellites on-board the rocket Friday brought the total number of Starlink spacecraft launched to 3,981.
The Federal Communications Commission granted SpaceX approval Dec. 1 to launch up to 7,500 of its planned 29,988-spacecraft Starlink Gen2 constellation. The regulatory agency deferred a decision on the remaining satellites SpaceX proposed for Gen2.
The FCC previously authorized SpaceX to launch and operate roughly 4,400 first-generation Ka-band and Ku-band Starlink spacecraft that SpaceX has been launching since 2019.
The Gen2 satellites could improve Starlink coverage over lower latitude regions, and help alleviate pressure on the network from growing consumer uptake. SpaceX said in December the network has more than 1 million active subscribers. The Starlink spacecraft beam broadband internet signals to consumers around the world, connectivity that is now available on all seven continents with testing underway at a research station in Antarctica.
Earlier this month, SpaceX announced Starlink service is now available in Brazil, Colombia, and Italy.
More than 3,500 Starlink satellites are currently in orbit and working, according to an analysis by Jonathan McDowell, an astrophysicist who tracks spaceflight activity. That’s more than three-quarters of SpaceX’s planned first-generation network of 4,400 Starlink satellites.
The launch Thursday was SpaceX’s 73rd mission primarily dedicated to deploying satellites for the Starlink network.
SpaceX plans more Starlink missions from Vandenberg in the next few weeks, as the company targets turnaround times at the Vandenberg launch site as short as 10 days between Falcon 9 flights. Overall, SpaceX is launching Falcon rockets at a pace of about one flight ever four days so far this year from launch pads in Florida and California.
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