Sixty more Internet Starlink satellites are set to launch into orbit Sunday night from Cape Canaveral on the 100th flight of a SpaceX Falcon 9 launcher and the seventh flight of SpaceX’s reusable “fleet leader” booster.
The Falcon 9 rocket is scheduled to launch at 9:56:21 PM EST on Sunday (0256:21 GMT on Monday) from Pad 40 at Cape Canaveral Air Force Station. The mission is expected to take off less than 34 hours after SpaceX’s previous flight, a Falcon 9 launch from California that brought an oceanographic satellite designed to measure sea level rise into orbit.
The launch of Falcon 9 with the Michael Freilich Sentinel-6 oceanographic satellite on Saturday was SpaceX’s 22nd mission of 2020, breaking the company’s record for the most launches in a calendar year. Sunday’s flight will extend the record.
While the launch of the Falcon 9 from California took place with a factory-fresh first booster, the SpaceX launch from Florida on Sunday night will use a booster that has flown six times earlier. The seventh flight of the rocket will set a new record for SpaceX’s rocket reuse program, breaking a mark set by the booster itself on its sixth mission in August.
The rocket ready for launch on Sunday – known as the B1049 – debuted in September 2018 with the launch of the Telstar 18 VANTAGE geostationary communications satellite from Cape Canaveral. It was launched again from the Vandenberg Air Force Base in California in January 2019 with 10 Iridium data and voice satellites.
The booster flew again in May 2019 with SpaceX’s first set of 60 Internet Starlink satellites, followed by three more Starlink missions on January 6, June 3, and August 18.
“This launch will make him the leader of the fleet,” SpaceX tweeted of the booster on Saturday.
There’s a 60% chance of good weather in Cape Canaveral for launch Sunday night, according to the US Space Force’s 45th Meteorological Squadron. The main weather concerns relate to cumulus clouds and disturbed weather associated with scattered rains along the Florida space coast.
SpaceX tested the rocket’s nine Merlin 1D engines on Saturday at 4:00 PM EST (2100 GMT). The engines fired for several seconds as the retaining clamps held the rocket firmly on pad 40, sending a low rumble through the Cape Canaveral spaceport.
The launch team originally planned to test the rocket early Friday before a potential launch attempt on Saturday night, but SpaceX halted the test in the final moments before ignition. After unloading the propellant from the rocket, SpaceX refilled the Falcon 9 during a test countdown on Saturday afternoon, culminating in the successful 4:00 pm test launch.
SpaceX will re-load the kerosene and liquid oxygen propellants into the rocket on Sunday evening starting at 9:21 PM EST (0221 GMT). The automated countdown will proceed through propellant loading, final steering system checks and pressurization before giving the command to start the nine Merlin 1D engines at T-minus 3 seconds.
The restrictions will open to allow the 229-foot (70-meter) tall Falcon 9 rocket to move away from Pad 40 with 1.7 million pounds of thrust from its Merlin main engines.
Heading northeast from Cape Canaveral, the rocket’s first stage booster will separate for about two and a half minutes into the mission, aiming for a landing on SpaceX’s drone ship “Of Course I Still Love You” at around 400 miles (650 kilometers) northeast of the launch site.
The booster should land on the floating platform at T + plus 8 minutes 44 seconds, moments before the Falcon 9 upper stage engine shuts down. The top level will deploy 60 Starlink flat screen T + satellites plus 14 minutes 44 seconds. seconds, according to a mission timeline released by SpaceX.
The rocket will aim to position the satellites in an elliptical orbit between 132 miles (213 kilometers) and 227 miles (366 kilometers), with an inclination of 53 degrees relative to the equator.
The quarter-tonne satellites, built by SpaceX in Redmond, Washington, are expected to deploy the solar arrays that generate energy and prepare their krypton-ion thrusters to begin increasing their orbits to an operating altitude of 550. kilometers, more than 800 other Starlink relay stations to transmit broadband Internet signals to most of the populated world.
With the launch on Sunday, SpaceX will have deployed 955 Starlink satellites into orbit since May 2019.
SpaceX plans to manage an initial block of approximately 1,500 Starlink satellites in orbit 341 miles above Earth. The company, founded by billionaire Elon Musk, has regulatory approval from the Federal Communications Commission to field a fleet of up to 12,000 small Starlink broadband stations operating in the Ku, Ka 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 cleared by the FCC.
SpaceX says the Starlink network, designed for low-latency Internet service, has entered beta testing in multiple states in the United States and Canada.
“Last month, SpaceX launched its” Better Than Nothing Beta “testing program,” the company said in a post on its website. “Service invitations were sent to a portion of those who requested availability updates on Starlink.com and who live in serviceable areas. A couple of weeks ago, Canada granted regulatory approval to Starlink and last week SpaceX rolled out the service in parts of southern Canada. “
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