Live coverage of the countdown and launch of the SpaceX Falcon 9 rocket from Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The Starlink 4-25 mission will launch SpaceX’s next 53 Starlink broadband satellites. Follow us Twitter.
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SpaceX on Sunday sent 53 Starlink Internet satellites into orbit aboard a Falcon 9 rocket, the company’s 33rd mission of the year and sixth launch in July. Liftoff from Pad 39A at NASA’s Kennedy Space Center in Florida occurred at 9:38 a.m. EDT (1338 GMT).
A Falcon 9 booster landed on SpaceX’s drone ship docked in the Atlantic Ocean northeast of Cape Canaveral.
The rocket headed northeast from Kennedy Space Center, aiming to deliver flat-pack broadband relay stations to an orbit 144 miles by 210 miles high (232-by-338 kilometers). The launch of 53 flat-packed satellites from the upper stage of Falcon 9 occurred 15 minutes after lift off.
With Sunday’s mission designated Starlink 4-25, SpaceX has launched 2,957 Starlink Internet satellites, including prototypes and test units out of service. Sunday’s launch marked the 53rd SpaceX mission dedicated to pulling Starlink Internet satellites into orbit.
Stationed inside the firing chamber at the Missile Control Center at Kennedy, the SpaceX launch team began loading supercooled, dense kerosene and liquid oxygen propellants into the 229-foot-tall (70-meter) Falcon 9 vehicle in T-minus 35 minutes.
During the last half-hour of the countdown, helium pressure was also released into the rocket. In the seven minutes before liftoff, the Falcon 9’s Merlin main engines were thermally stabilized for flight through a process known as “chill down.” The Falcon 9’s guidance and range protection systems were also configured for launch.
After liftoff, the Falcon 9 rocket fired its 1.7 million pounds of thrust — produced by nine Merlin engines — in a northeasterly direction over the Atlantic Ocean.
The rocket surpassed the speed of sound in about a minute, then stopped two and a half minutes after lifting off its nine main engines. The booster stage was released from the upper stage of the Falcon 9, then the cold gas control thrust and extended titanium grid ejected pulses from the fins, helping to propel the vehicle back into the atmosphere.
Two braking burns slowed the rocket to land aboard the drone, “A Shortfall of Gravitas,” after about eight and a half minutes from a distance of about 400 miles (650 kilometers).
The Starlink 4-25 mission, known as B1062, was the eighth launch of the booster into space. It launched the US military GPS navigation satellite in November 2020, and launched all private Inspiration4 and Axiom-1 crewed missions in September 2021 and April this year.
Most recently, the booster flew on June 8 with the Egyptian Nilesat 301 geospatial communications satellite.
The first stage on Sunday’s mission landed minutes after the Falcon 9’s second stage engine cut off to launch the Starlink satellites into orbit. 53, built by SpaceX in Redmond, Washington, was T+Plus 15 minutes, 24 seconds aboard a Falcon 9 rocket.
Retention rods released from the Starlink payload stack allow the flat-packed satellites to fly freely from the top position of the orbiting Falcon 9. 53 spacecraft will expand the solar arrays and run through automated activation steps, then use krypton-fueled ion engines to maneuver into their operational orbits.
Falcon 9’s guidance system aims to position the satellites in an elliptical orbit at an orbital inclination of 53.2 degrees to the equator. Satellites use on-board propulsion to do the rest of the work to reach a circular orbit about 335 miles (540 kilometers) from Earth.
Starlink satellites will fly in one of five orbital “shells” at different inclinations for SpaceX’s global Internet network. After reaching their operational orbit, the satellites will enter commercial service and begin beaming broadband signals to customers, who can purchase Starlink service and connect to the network with a ground terminal provided by SpaceX.
Including Sunday’s Starlink 4-25 mission, SpaceX has launched six Falcon 9 rockets in 17 days this month, deploying 251 Starlink Internet satellites on five flights, while sending a Dragon cargo capsule to the International Space Station.
Rocket: Falcon 9 (B1062.8)
Payload: 53 Starlink satellites (Starlink 4-25)
Launch the site: LC-39A, Kennedy Space Center, Florida
Release Date: July 24, 2022
Release Time: 9:38:20 a.m. EDT (1338:20 GMT)
Weather forecast: 80% chance of acceptable weather; Low risk of upper level winds; Low risk of unfavorable conditions for booster recovery
Booster recovery: A “lack of gravitas” drone cruises east of Charleston, South Carolina
Initialize the azimuth: Northeast
Target Orbit: 144 miles by 210 miles (232 kilometers by 338 kilometers), 53.2 degree gradient
Start the timeline:
- D+00:00: Liftoff
- T+01:12: Maximum Aerodynamic Pressure (Max-Q)
- T+02:27: First Stage Main Engine Cut (MECO)
- T+02:30: Phase separation
- T+02:37: Secondary engine ignition
- T+02:42: Fairing jettisoned
- T+06:48: First Stage Inlet Combustion Ignition (Three Engines)
- T+07:08: First stage inlet combustion cut
- T+08:25: First stage landing flare ignition (one engine)
- T+08:43: Secondary mechanical cut (SECO 1)
- T+08:46: First stage landing
- T+15:24: Starlink satellite separation
Working Statistics:
- 167th launch of a Falcon 9 rocket since 2010
- 175th launch of the Falcon rocket family since 2006
- 8th release of Falcon 9 booster B1062
- 144th Falcon 9 launch from Florida’s Space Coast
- 52nd SpaceX launch from Pad 39A
- 146th release overall from pad 39A
- 109th flight of a reused Falcon 9 booster
- 53rd dedicated Falcon 9 launch with Starlink satellites
- 33rd Falcon 9 launch of 2022
- SpaceX’s 33rd launch in 2022
- 32nd orbital launch attempt from Cape Canaveral in 2022
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