The oldest Falcon 9 booster in SpaceX’s operational rocket fleet sent 60 more Starlink Internet satellites into space on Tuesday with a launch from historic pad 39A at NASA’s Kennedy Space Center in Florida.
With the 60 satellites launched on Tuesday, SpaceX has sent 1,565 Starlink spacecraft into orbit to radiate broadband signals around the world, nearly nine times as many satellites in any other company’s constellation.
The 229-meter-high (70-meter) Falcon 9 rocket climbed away from the Florida spaceport and rumbled through a sunny afternoon sky and flew on a track northeast of the Kennedy Space Center to place 60 more Starlink broadband stations in orbit.
The mission began at 15:01 EDT (1901 GMT) on Tuesday as nine petroleum-powered Merlin 1D booster engines fired up to propel the 1.2 million-pound Falcon 9 launch vehicle from the pad.
Falcon 9 exceeded the speed of sound by approx. one minute, then shut down the engines in the first stage and released the booster about two and a half minutes after liftoff.
Repeal of SpaceX’s Falcon 9 rocket launching the next 60 Starlink satellites into orbit. https://t.co/NPEygGCRNT pic.twitter.com/1HQQXcYHia
Spaceflight Now (@SpaceflightNow) May 4, 2021
The 15-story booster stage – designated B1049 in SpaceX’s fleet – continued to run toward the peak of its suborbital orbit, unfolding aerodynamic lattice winds to help stabilize the rocket for descent back through the atmosphere.
Three of the booster’s Merlin engines re-ignited for an input combustion, and the rocket’s central engine ignited for a landing combustion just before the first stage extended its legs and landed on the deck of SpaceX’s drone ship “Of Course I Still Love You” for a bullseye touchdown in the Atlantic.
The landing about eight and a half minutes after takeoff punctured the ninth journey into space and back to this booster, which debuted in September 2018. This reusable booster is the oldest operational first phase in SpaceX’s inventory and its nine launches and landings tie another boost to the largest number of aircraft in the Falcon 9 fleet.
SpaceX plans to return the drone ship and Falcon 9 booster to Port Canaveral, Florida, from the recovery area a few hundred miles east of Charleston, South Carolina. Ground crews at Cape Canaveral are expected to inspect and renovate the rocket for a 10th flight.
The Falcon 9’s second stage engine completed two incinerations to place the 60 Starlink satellites in the right orbit for deployment. About 64 minutes after the liftoff, a forward-facing camera on the top step showed the 60 flat-screen satellites flying free of the rocket at an altitude of 293 kilometers south of New Zealand.
The 573-pound (260-kilogram) satellites will deploy their power-generating solar panels and turn on their krypton-powered plasma projectors to raise their altitude to 550 kilometers to join the rest of the Starlink fleet.
The launch on Tuesday marked the 100th equally successful Falcon 9 or Falcon Heavy mission without in-flight failure, a streak that stretched back to June 2015. It was the 91st successful mission for SpaceX when a Falcon 9 rocket exploded during a test before the flight at Cape Canaveral in September 2016 and destroyed the launch vehicle and an Israeli-owned communications satellite, damaging SpaceX’s launch pad.
The Starlink satellites are built on SpaceX’s assembly line in Redmond, Washington.
The 1,565 Starlink satellites launched today include prototypes and failed spacecraft that have fallen out of orbit and burned up in the atmosphere. Jonathan McDowell, an astronomer and expert tracker of spaceflight activity, says more than 1,400 Starlink satellites are currently in orbit, not counting the 60 spacecraft launched Wednesday night.
The Federal Communications Commission has approved SpaceX to deploy about 12,000 Starlink satellites operating at Ku-band, Ka-band and V-band frequencies and at a range of heights and inclinations in low-Earth orbit. The satellites already radiate low latency broadband signals to users who have signed up for the Starlink beta test.
All 60 Starlink Internet satellites have been launched from the rocket at an altitude of 293 km south of New Zealand.
With this flight, SpaceX has launched 100 straight Falcon 9 and Falcon Heavy rockets without a failed mission flight. Https://t.co/NPEygGCRNT pic.twitter.com/gfD6GEtwQ6
Spaceflight Now (@SpaceflightNow) May 4, 2021
So far, almost all Starlink satellites launched by SpaceX operate in 341-kilometer-high orbits inclined at a 53-degree inclination to the equator.
“We have global reach, but we do not have full connectivity globally,” Gwynne Shotwell, President and CEO of SpaceX, said at an industry conference last month. “We hope that after approx. 28 launches have continuous coverage across the globe. And then the plan is then to continue adding satellites to provide additional capacity. ”
Launched Tuesday, the 25th Falcon 9 flight dedicated to pulling operational Starlink satellites, known as version 1.0, into orbit, and the 28th Falcon 9 mission assembled with Starlink payloads on board.
Last April, SpaceX requested approval from the FCC to operate its Starlink satellites at lower altitudes than originally planned, ranging from 540 kilometers to 570 kilometers. The FCC approved the request last month.
With the commission’s approval, SpaceX will now operate its first 4,408 satellites at altitudes between 335 miles and 354 miles instead of flying more than 2,800 of the spacecraft in orbits as high as 800 miles or 1,300 kilometers above Earth.
FCC approval paves the way for SpaceX to launch more Starlink satellites into polar orbit later this year. The polar orbiting satellites provide the Starlink network with complete global coverage.
The updated Starlink network architecture has 1,584 satellites at 550 kilometers altitude and an inclination of 53 degrees, 1,584 satellites at 335 miles (540 kilometers) and an inclination of 53.2 degrees, 720 satellites at 354 miles (570 kilometers) and an inclination of 70 degrees and 520 satellites at 560 kilometers and an inclination of 97.6 degrees.
SpaceX is still legally authorized to launch more than 7,000 additional Starlink satellites in addition to the 4,408 spacecraft covered by the recent FCC approval.
The next Falcon 9 launch is scheduled for 02.42 EDT (0642 GMT) Sunday from pad 40 at Cape Canaveral Space Force Station carrying the next batch of Starlink internet satellites.
Another Starlink mission is scheduled for mid-May with a Falcon 9 launch from pad 39A.
Email the author.
Follow Stephen Clark on Twitter: @ StephenClark1.