Live streaming of the countdown and launch of SpaceX’s 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 batch of 53 broadband Starlink satellites. Follow us on Twitter.
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SpaceX sent another cluster of 53 Starlink Internet satellites into orbit Sunday 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).
The Falcon 9 booster landed on SpaceX’s unmanned spacecraft parked down in the Atlantic Ocean northeast of Cape Canaveral.
The rocket headed northeast from Kennedy Space Center, aiming to deliver the flat-pack broadband relay stations to an orbit varying between 144 miles and 210 miles high (232 by 338 kilometers). Deployment of the 53 flat satellites from the Falcon 9 upper stage occurred about 15 minutes after liftoff.
With Sunday’s mission, designated Starlink 4-25, SpaceX launched 2,957 Starlink Internet satellites, including prototypes and test units that are no longer in service. Sunday’s launch marked SpaceX’s 53rd mission, dedicated primarily to putting Starlink Internet satellites into orbit.
Located in a launch hall at Kennedy Launch Control Center, the SpaceX launch team began loading supercooled, condensed kerosene and liquid oxygen into the 229-foot (70-meter) Falcon 9 vehicle at T-minus 35 minutes.
During the last half hour of the countdown, pressurized helium also leaked into the rocket. In the final seven minutes before liftoff, Falcon 9’s main Merlin engines were thermally conditioned for flight through a procedure known as “cooling down.” Falcon 9’s guidance and safety systems were also configured for launch.
After liftoff, the Falcon 9 rocket directed 1.7 million pounds of thrust produced by nine Merlin engines to head northeast over the Atlantic Ocean.
The rocket exceeded the speed of sound for about one minute, then shut down its nine main engines two and a half minutes after liftoff. The booster stage broke free from the Falcon 9’s upper stage, then fired pulses of cold gas thrusters and expanded titanium arrays to help guide the vehicle back into the atmosphere.
Two brake burns slowed the rocket to land on the A Shortfall of Gravitas unmanned craft about 400 miles (650 kilometers) down roughly eight and a half minutes after liftoff.
Credit: Spaceflight Now
The booster flying on the Starlink 4-25 mission, known as B1062, blasted off on its eighth trip into space. It debuted with the launch of a US military GPS navigation satellite in November 2020 and launched the fully crewed Inspiration4 and Axiom-1 missions in September 2021 and in April this year.
Most recently, the booster lifted off on June 8 with Egypt’s Nilesat 301 geostationary communications satellite.
Sunday’s landing of the mission’s first stage occurred moments after the Falcon 9’s second stage engine cut off to deliver the Starlink satellites into orbit. The separation of the 53 spacecraft, built by SpaceX in Redmond, Washington, from the Falcon 9 rocket occurred at T+plus 15 minutes, 24 seconds.
Retention rods released from the Starlink payload stack, allowing the planar satellites to fly free from the Falcon 9 upper stage in orbit. Spacecraft 53 will deploy solar arrays and go through automated activation steps, then use krypton-fueled ion thrusters to maneuver into their operational orbit.
Falcon 9’s guidance computer was intended to place the satellites in an elliptical orbit at an orbital inclination of 53.2 degrees to 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.
The Starlink satellites will fly in one of five orbital “shells” at different inclinations for SpaceX’s global internet network. Once they reach their operating orbit, the satellites will enter commercial service and begin broadcasting broadband signals to users 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 launched six Falcon 9 rockets in just 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 SITE: LC-39A, Kennedy Space Center, Florida
RELEASE DATE: July 24, 2022
START TIME: 9:38:20 AM EDT (1338:20 GMT)
WEATHER FORECAST: 80% chance of fair weather; Low risk of upper level winds; Low risk of adverse conditions for booster recovery
BOOSTER RECOVERY: ‘A Shortfall of Gravitas’ drone ship east of Charleston, South Carolina
LAUNCH AZIMUTH: Northeast
TARGET ORBIT: 144 miles by 210 miles (232 kilometers by 338 kilometers), 53.2 degree inclination
LAUNCH SCHEDULE:
- T+00:00: Take off
- T+01:12: Maximum aerodynamic pressure (Max-Q)
- T+02:27: First Stage Main Engine Shutdown (MECO)
- T+02:30: Stage split
- T+02:37: Second stage engine ignition
- T+02:42: Fairing jettisoning
- T+06:48: Ignition of first entry stage (three engines)
- T+07:08: Interrupt burn on first stage entry
- T+08:25: First stage landing ignition (one engine)
- T+08:43: Second stage engine shutdown (SECO 1)
- T+08:46: First stage landing
- T+15:24: Separation of Starlink satellites
MISSION STATISTICS:
- The 167th launch of a Falcon 9 rocket since 2010
- 175th launch of the Falcon rocket family since 2006
- 8th launch of Falcon 9 booster B1062
- The 144th Falcon 9 launch from Florida’s Space Coast
- SpaceX’s 52nd launch from pad 39A
- 146th launch overall from pad 39A
- 109th flight of a reusable Falcon 9 booster
- 53rd special launch of Falcon 9 with Starlink satellites
- 2022 Falcon 9’s 33rd launch
- 33rd launch from SpaceX in 2022
- 32nd orbital launch attempt from Cape Canaveral in 2022
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Follow Stephen Clark on Twitter: @StephenClark1.
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