Sixty more Starlink Internet satellites are ready to rocket into orbit Sunday night from Cape Canaveral on the 100th flight of a SpaceX Falcon 9 launch pad and the seventh flight of SpaceX’s reusable “fleet leader” booster.
The Falcon 9 rocket is scheduled to launch at 21:56:21 EST Sunday (0256: 21 GMT Monday) from pad 40 at Cape Canaveral Air Force Station. The mission is set to explode less than 34 hours after SpaceX’s previous flight, a Falcon 9 launch from California that orbited an oceanography satellite designed to measure sea levels.
The Falcon 9 launch with Sentinel-6 Michael Freilich oceanography satellite on Saturday was SpaceX’s 22nd mission in 2020, breaking the company’s record for most launches in a calendar year. Sunday’s flight expands the record.
While the Falcon 9 launch from California flew with a factory-fresh first phase booster, SpaceX’s launch from Florida on Sunday night will use a booster that has flown six times before. The seventh flight of the rocket will set a new record for SpaceX’s missile recycling program and break a mark set by the same booster on its sixth mission in August.
The rocket, which was launched on Sunday – known as B1049 – debuted in September 2018 with the launch of the Telstar 18 VANTAGE geostationary communications satellite from Cape Canaveral. It was launched again from Vandenberg Air Force Base in California in January 2019 with 10 Iridium voice and data relay satellites.
The booster flew again in May 2019 with SpaceX’s first set of 60 Starlink Internet satellites, followed by three more Starlink missions on January 6, June 3 and August 18.
“This launch will make it a fleet leader,” SpaceX tweeted about the booster on Saturday.
There is a 60 percent chance of favorable weather in Cape Canaveral for launch Sunday night, according to the U.S. Space Force’s 45th Weather Squadron. The main weather problems are with cumulus clouds and disturbed weather associated with scattered rain showers along Florida’s Space Coast.
SpaceX test-fired the rocket’s nine Merlin 1D engines at 16 EST (2100 GMT) Saturday. The engines ignited for several seconds while holding clamps held the rocket firmly on pad 40, sending a low rumble over Cape Canaveral spaceport.
The launch team originally planned to test the rocket early on Friday ahead of a potential launch attempt on Saturday night, but SpaceX interrupted the test in the final moments before ignition. After draining the propellant from the rocket, the SpaceX Falcon 9 refilled during a countdown of practice Saturday afternoon, culminating in the successful test firing at 1 p.m. 16
SpaceX will fill petroleum and liquid oxygen propellants into the rocket again on Sunday evening, starting at 21:21 EST (0221 GMT). The automatic countdown continues through drive reading, final operating system checks, and presses before issuing the command to ignite the nine Merlin 1D engines at T-minus 3 seconds.
Restrictions are being opened to allow the 229-meter-high (70-meter) Falcon 9 rocket to climb away from pad 40 with 1.7 million-pound stacks from its Merlin main engines.
On its way northeast from Cape Canaveral, the first stage of the rocket separates the booster about two and a half minutes into the mission and targets a landing on SpaceX’s drone ship “Of course I still love you” about 650 km northeast of the launch site.
The booster is scheduled to land on the floating platform at T + plus 8 minutes, 44 seconds, moments before shutting down the Falcon 9’s upper stepper motor. The top phase will deploy the 60 flat-screen Starlink satellites at T + plus 14 minutes, 44 seconds, according to a mission timeline released by SpaceX.
The rocket aims to place the satellites in an elliptical orbit that extends between 132 miles (213 kilometers) and 227 miles (366 kilometers) with an inclination of 53 degrees to the equator.
The quarter-ton satellites, built by SpaceX in Redmond, Washington, are expected to deploy solar systems and prime their krypton-ion thrusters to begin raising their orbits to an operational altitude of 550 kilometers, where they will join more than 800 other Starlink relay stations to transmit broadband Internet signals over most of the populated world.
With the launch on Sunday, SpaceX will have launched 955 Starlink satellites into orbit since May 2019.
SpaceX plans to operate a first block of about 1,500 Starlink satellites in orbits 341 miles above Earth. The company, founded by billionaire Elon Musk, has regulatory approval from the Federal Communications Commission to eventually deploy a fleet of up to 12,000 small Starlink broadband stations operating in Ku-band, Ka-band and V-band frequencies.
There are also preliminary plans for an even larger fleet of 30,000 additional Starlink satellites, but a network of that size has not been approved by the FCC.
SpaceX says the Starlink network – designed for low-latency Internet – has entered a beta test phase in several US states and Canada.
“Last month, SpaceX launched its ‘Better Than Nothing Beta’ test program,” the company said in a post on its website. Service invitations were sent to some of those who requested availability updates on Starlink.com and who live in serviceable areas. A few weeks ago, Canada issued Starlink regulatory approval, and last week, SpaceX rolled out the service to parts of southern Canada. ”
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