53 more Starlink satellites are deployed by SpaceX on its record-tying 31st launch of the year

On Sunday, SpaceX launched its 31st vehicle of the year, carrying 53 additional Starlink broadband satellites into orbit from Cape Canaveral. This tied the company’s total for 2021 and kept its one flight per week schedule.

At 10:20 a.m. EDT (1420 GMT) on Sunday, the Falcon 9 rocket blasted off from pad 40 at Cape Canaveral Space Force Station. The Falcon 9 launcher was propelled off the launch pad by nine Merlin 1D engines, which ignited with 1.7 million pounds of thrust and consumed rocket-grade kerosene fuel.

The Falcon 9 lifted off as thunderstorms and showers moved over the spaceport, heading northeast as it flew over the Atlantic Ocean and climbed through sporadic clouds. About two and a half minutes into the flight, the launcher shut down its first stage engines after passing past the speed of sound in less than a minute.

Using four titanium grid fins for control and a brake burn with three of its engines to slow down re-entry, the first stage separated from the upper stage and arced to a peak height of approximately 84 miles (135 kilometres).

About 400 miles (650 kilometres) northeast of Cape Canaveral, the rocket extended four landing legs and performed a final landing burn using the booster’s centre engine. The rocket then landed on the deck of the drone ship “Just Read the Instructions.” The touchdown on the drone ship the size of a football field was the 131st Falcon booster landing and the 13th launch of this first stage, identified as tail number B1051.

One of SpaceX’s older reusable rocket boosters is this one. B1051 made its public debut in March 2019 alongside SpaceX’s Crew Dragon’s first test flight without a pilot. Since then, the booster has launched nine Starlink missions as well as the Canadian Radarsat Constellation Mission, SiriusXM’s SXM 7, and Canada’s Radarsat Constellation Mission.

B1051 has already launched 582 satellites during the course of its career, which has lasted more than three years. It is the third rocket in SpaceX’s stockpile to accomplish the 13-flight milestone. The latest Falcon 9 booster generation has been certified by SpaceX for at least 15 missions, an increase over the original certification of 10 flights.

Similar to the majority of SpaceX’s recent Starlink missions, Sunday’s launch, known as Starlink 4-22, used the Falcon 9’s guidance computer to aim for an elliptical orbit with an altitude between 144 miles and 210 miles (232-by-338 kilometers).

The upper stage of the Falcon 9 burned its lone Merlin for almost T+plus 9 minutes. The Falcon 9 jettisoned all of its nose shrouds while the upper stage was igniting. The fairing shells will be recovered from the water by a SpaceX recovery ship in the Atlantic once they have descended using parachutes. According to SpaceX, Sunday’s launch marked the 50th time that fairing shells from a Falcon rocket had been reused.

At T+plus 15 minutes, 28 seconds after engine cutoff, the second stage released the 53 Starlink satellites after coasting across the North Atlantic Ocean.

Before the Starlink satellites were launched, the upper stage spun itself up. The Falcon 9 rocket released retaining rods that hold the satellites firmly fastened to the spacecraft during ascent, allowing the flat-packed satellites, each weighing more than a quarter of a tonne, to fly free of the rocket.

The satellites will spread out once they are released from the rocket, unfold their solar panels, and start their krypton-fueled ion motors to soar to a height of 335 miles (540 kilometers).

Customers of SpaceX all around the world can access broadband internet service through the Starlink satellites, each of which weighs more than a quarter of a tonne at launch. The spacecraft is produced by SpaceX in Redmond, Washington.

With the launch of the 53 satellites on Sunday, SpaceX will have sent 2,858 Starlink spacecraft into orbit, including prototypes and retired satellites. According to Jonathan McDowell, an astrophysicist and professional tracker of spaceflight activity, SpaceX currently has more than 2,500 Starlink satellites operating in orbit, either in service or manoeuvring to their final operating orbits.

The constellation of 428 internet satellites owned by OneWeb, the second-largest fleet of spacecraft in orbit, has nearly half as many satellites as that.

4,408 operational satellites will fly in five orbital “shells” at various inclinations in SpaceX’s first-generation network. The Federal Communications Commission has given SpaceX permission to operate up to 12,000 Starlink satellites, and SpaceX has hinted that it may launch more satellites if there is sufficient commercial demand.

After earlier Falcon 9/Starlink launches from Cape Canaveral on July 7 and from the Californian Vandenberg Space Force Base on July 10, Sunday’s launch marked the fourth SpaceX mission of the month of July. On Thursday, a Dragon cargo ship headed for the International Space Station was launched by a Falcon 9 rocket from the Kennedy Space Center.

SpaceX is on course to almost treble its launch cadence from 2021, with 31 flights already completed this year. Last year, SpaceX conducted 31 Falcon 9 flights, and in 2020, it will launch 26 Falcon 9 rockets.

High demand for Starlink flights, faster rocket refurbishment, and greater utilisation of SpaceX’s launch facility at California’s Vandenberg Space Force Base, which has already hosted six Falcon 9 launches this year, have all contributed to the improved flight rate. Only three Falcon 9 launches from California occurred in 2018 and only one SpaceX flight will take place there in 2020.

Within the coming week, SpaceX intends to launch two additional rockets, each of which will add more Starlink satellites to the commercial broadband network. On Thursday, a Falcon 9 rocket is scheduled to launch from Vandenberg, and on July 24, a second Falcon 9 is planned to launch from Florida’s Kennedy Space Center.