The 40th dedicated launch for SpaceX’s Starlink internet network is set to blast off from Cape Canaveral on Wednesday, adding 48 more broadband relay nodes to the ever-growing, privately-owned satellite constellation.
Since the first test satellites launched in 2018, SpaceX has delivered 2,234 Starlink satellites to orbit on Falcon 9 rockets. Nearly 2,000 of those satellites are currently functioning in low Earth orbit, according to a tabulation maintained by Jonathan McDowell, an astrophysicist and expert tracker of spaceflight activity.
That’s more than quadruple the number of satellites currently flying in the second-largest fleet of spacecraft — the internet constellation owned by Starlink rival OneWeb. In third place is Planet, which operates a fleet of more than 200 small Earth-imaging satellites.
The launch Wednesday will be the 40th Falcon 9 flight to carry Starlink satellites as a primary payload.
SpaceX is in the midst of launching around 4,400 Starlink satellites into five orbital “shells” more than 300 miles above Earth. The shells are positioned at different inclinations, and SpaceX completed launches of the first of the five Starlink groups last May.
Ultimately, SpaceX intends to launch as many as 42,000 internet satellites. The final figure hinges on market demand for the Starlink service, which offers high-speed, low-latency connectivity.
SpaceX says the service is best suited for customers in remote, hard-to-reach areas, such as rural communities, isolated homes, islands, and ships. SpaceX has also partnered with the U.S. military to demonstrate Starlink connectivity to airplanes.
Users in Ukraine are also relying on the Starlink network to provide independent access to the internet during Russia’s military invasion of the country. SpaceX turned on service to Ukraine in late February, and shipped a batch of Starlink user terminals to Ukraine days after the invasion started, responding to a request from Ukraine’s vice prime minister.
Elon Musk, SpaceX’s founder and CEO, tweeted March 4 that SpaceX is reprioritizing efforts to emphasize cyber defense and “overcoming signal jamming.”
“Some Starlink terminals near conflict areas were being jammed for several hours at a time,” Musk tweeted. “Our latest software update bypasses the jamming.”
Without elaborating, he said the reprioritization “will cause slight delays” in SpaceX’s Starship heavy-lift rocket program, a fully reusable launch vehicle in development ferry massive cargo and humans into deep space. The effort will also cause slight delays in Starlink V2, the next generation of Starlink satellites designed to launch on Starship.
But the Falcon 9 launch schedule continues unchanged.
A Falcon 9 is positioned vertical on Space Launch Complex 40 at Cape Canaveral for liftoff at 8:45 a.m. EST (1345 GMT) Wednesday. SpaceX has a backup launch opportunity available at 10:04 a.m. EST (1504 GMT).
The mission will continue SpaceX’s weekly launch cadence this year. It will be SpaceX’s 10th mission of 2022, and comes six days after the most recent Starlink mission on March 3.
Wednesday’s mission, designated Starlink 4-10, will mimic SpaceX’s recent Starlink launches from Florida’s Space Coast. The Falcon 9 rocket, powered by nine Merlin 1D engines, will steer southeast from Cape Canaveral Space Force Station.
Arcing over the Atlantic Ocean, the rocket’s first stage booster will turn off its main engines and separate from the Falcon 9’s upper stage at T+plus 2 minutes, 34 seconds. While the second stage powers into orbit with the 48 Starlink satellites, the first stage will come back to Earth for a landing on SpaceX’s drone ship “A Shortfall of Gravitas” parked in the Atlantic northeast of the Bahamas.
The reusable booster flying Tuesday is poised for its fourth launch into space. The rocket, tail number B1052, flew its first two missions as a side booster on SpaceX’s Falcon Heavy rocket. After a conversion effort, SpaceX flew the booster again as the first stage of a Falcon 9 rocket Jan. 31 with an Italian radar remote sensing satellite.
Now, 37 days later, the booster is ready to take off for a fourth time. After a hypersonic descent back into the atmosphere, rocket will aim to land on SpaceX’s drone ship at T+plus 8 minutes, 51 seconds, around 400 miles (650 kilometers) southeast of Cape Canaveral. The vessel will return the booster to Port Canaveral for offloading and refurbishment before another mission.
The second stage will shut down at T+plus 8 minutes, 45 seconds, after reaching a parking orbit. Following a 48-minute coast halfway around the world, the Falcon 9 will relight its second stage engine for one-second burn to place the Starlink satellites into the proper orbit for deployment.
The Falcon 9 is programmed to releases the flat-packed satellites, each weighing about a quarter-ton, nearly 66 minutes after launch. The rocket’s guidance computer will target an orbit ranging between 189 miles and 197 miles (305-by-317 kilometers) in altitude, with an inclination of 53.2 degrees to the equator.
The Starlink satellites will extend solar arrays and use on-board ion thrusters to reach their operational orbit at an altitude of 335 miles (540 kilometers), where they will enter commercial service for SpaceX.
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