SpaceX launched a Falcon 9 rocket from Kennedy Space Center at dawn on Friday with 53 Starlink internet satellites, ending a sleepless night of space operations just five hours after sending four astronauts back in a splash off the west coast of Florida.
Lighting up the skies above the Florida Space Coast, a Falcon 9 rocket fired nine Merlin main engines and climbed from pad 39A in Kennedy at 5:42 a.m. EDT (0942 GMT) Friday. SpaceX returned a Dragon capsule to Earth at 12:43 a.m. EDT (0443 GMT), bringing home a crew of four from the International Space Station.
Friday’s launch was the seventh Falcon 9 mission since April 1, a pace close to the planned cadence of one launch every five days recently announced by SpaceX founder Elon Musk. SpaceX is planning up to 60 Falcon rocket missions this year from the company’s three operational launch pads.
Two of the April launches carried crews to the space station.
“It’s a pretty special moment for us,” said Bill Gerstenmaier, vice president of construction and flight reliability for SpaceX, during a press briefing in the early hours of Friday morning between the splashdown of the crew and launch of Starlink.
“I think what’s good here at SpaceX is that we have individual teams that track all of these activities, and they focus on their individual piece, and each of them is working in their own area,” said said Gerstenmaier. “We always share information with each other, and that helps us keep spacecraft safe.
“So when we do these additional Starlink launches, we actually learn things that we can then take and inform the crew flights, and make sure that the Falcon 9s associated with the crew flights are actually better than ‘they wouldn’t have been if we hadn’t been doing those Starlink flights,’ he said.
“I think now is a great time to be in spaceflight, to think that we’re well positioned as a company to support those multiple activities,” said Gerstenmaier, a former NASA engineer and program manager. “Our heads don’t turn around. We are really focused on each individual activity, and we can do them one at a time.
NASA has a multi-billion dollar contract with SpaceX to provide crew transport services to the space station. Along with SpaceX’s commercial launches, NASA engineers have a responsibility to ensure the agency’s astronaut missions launch and land safely.
“SpaceX has a tremendous amount of automation in place in terms of data review,” said Steve Stich, NASA commercial crew program manager. “They can do things quickly. They produce huge reports of a launch or a docking operation, and then we can take that data and digest it very quickly.
The company also pays “attention to detail” and ensures that “we perform every operation that requires labor and precision, carefully and correctly,” Stich said. “I’ve seen SpaceX pull back and take a time out at times when maybe they feel like the team needs a break and some rest.
“And then I saw us making good decisions together, where we have to step in and sometimes you have to do extra work on the vehicle to make it safer. So it’s an exciting time. We learn from every flight.
Friday morning’s launch marked the 152nd flight of SpaceX’s Falcon 9 rocket and the company’s 18th launch of the year. It was the 44th SpaceX mission primarily dedicated to launching satellites for the company’s privately funded Starlink broadband network.
Cloud cover over the launch pad marred the view for onlookers closer to the pad, but the timing of the launch, about an hour before sunrise, yielded dramatic results for skywatchers in other parts of Florida and along the eastern seaboard of the United States as the Falcon 9 soared into sunlight. The rocket headed northeast from Cape Canaveral to target one of the orbital planes, or lanes, in the Starlink constellation.
The Falcon 9 first stage, tail number B1058 in SpaceX’s inventory, halted about two and a half minutes after liftoff to begin a descent toward the company’s “A Shortfall of Gravitas” drone parked a few hundred kilometers downstream from the Atlantic. Ocean.
The push-off landing took place about eight and a half minutes after liftoff, moments before the Falcon 9’s second-stage engine completed its first firing to place the 53 Starlink satellites into a parking orbit. The booster stage became the third in SpaceX’s fleet to fly 12 times, the current record for Falcon 9 stages.
This booster debuted in May 2020 with the launch of the first test flight of SpaceX’s Dragon spacecraft to carry astronauts. With Friday morning’s launch, the booster helped carry 637 satellites and two people into space.
Falcon 9 reignited the upper stage Merlin-Vacuum engine approximately 45 minutes into the mission, setting the stage for separation of the 53 Starlink satellites at T+ plus 54 minutes, 30 seconds. SpaceX has confirmed a good payload deployment.
Retention rods holding the satellites in a flat configuration on the jettisoned rocket, allowing Starlink platforms to move away from the second stage. They will deploy solar arrays and go through automated activation stages, then use krypton-powered ion engines to maneuver into their operational orbit.
The Falcon 9 aimed to deploy the satellites in a near-circular orbit ranging in altitude from 189 miles to 197 miles (304 by 317 kilometers), at an orbital inclination of 53.2 degrees from the equator. The satellites will use onboard propulsion to do the rest of the work to reach a circular orbit 335 miles (540 kilometers) above Earth.
Friday’s mission’s Starlink satellites will fly in one of five orbital “shells” used in SpaceX’s global internet network. After ascending to their operational orbit, the satellites will enter commercial service and begin transmitting broadband signals to consumers, who can purchase Starlink service and connect to the network with a ground terminal provided by SpaceX.
After Friday’s launch, designated Starlink 4-17, SpaceX deployed 2,494 Starlink satellites into orbit, including spacecraft that have been taken out of service or experienced failures. More than 2,100 of those satellites are in orbit and functioning this week, according to a list kept by Jonathan McDowell, an astrophysicist who tracks spaceflight activity.
This makes the Starlink fleet the largest satellite constellation in the world, by a factor of nearly five over the internet satellite fleet owned by rival OneWeb.
SpaceX is launching some 4,400 Starlink satellites into the network’s five orbital shells. The first of five shells was filled last year, and SpaceX is expected to start rolling out additional shells later this year. All orbits are between 335 and 350 miles above Earth, while some are in medium-inclination orbits — like the orbit targeted during Friday’s mission — and others are in polar orbits.
The next launch of SpaceX’s Falcon 9, also carrying Starlink internet satellites, is scheduled for Tuesday, May 10 from Vandenberg Space Force Base, California.
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