Live coverage of the countdown and launch of a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida. The Starlink 4-12 mission will launch SpaceX’s next batch of 53 Starlink broadband satellites. Follow us on Twitter.
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Fifty-three more of SpaceX’s Starlink internet satellites rode into orbit atop a Falcon 9 rocket after midnight Saturday from Cape Canaveral. The reusable Falcon 9 booster completed its 12th successful mission to space, making it the fleet-leader in SpaceX’s inventory. Liftoff occurred at 12:42 a.m. EDT (0442 GMT).
The booster flying early Saturday, designated B1051, landed on SpaceX’s drone ship “Just Read the Instructions” parked around 400 miles (640 kilometers) downrange in the Atlantic Ocean, roughly due east of Charleston, South Carolina.
The mission, numbered Starlink 4-12 in SpaceX’s launch schedule, marked the resumption of Falcon 9 launches toward the northeast from Florida’s Space Coast. Since the start of the year, SpaceX’s launches with Starlink satellites have headed southeast, taking a different route to the same orbit at an inclination of 53.2 degrees to the equator.
SpaceX changed the direction of its launches in the winter months because of better odds that downrange weather will be acceptable near the Bahamas than in a booster landing zone northeast of Cape Canaveral.
The Starlink 4-12 aimed to deliver another batch of spacecraft into orbit for SpaceX’s privately-funded Starlink broadband network, the company’s sixth straight launch dedicated to lofting satellites for the internet mega-constellation.
SpaceX said Friday night it was moving the launch to a backup opportunity due to bad weather over Cape Canaveral, bypassing the first available launch time of 11:23 p.m. EDT (0323 GMT).
In the official launch weather forecast, meteorologists from the U.S. Space Force’s 45th Weather Squadron at Cape Canaveral predict a 70% chance of favorable conditions for liftoff of the Falcon 9 rocket overnight Friday into Saturday.
The booster flying on the Starlink 4-12 mission debuted in March 2019 with the unpiloted test flight of SpaceX’s Crew Dragon spacecraft, which paved the way for subsequent SpaceX launches with astronauts. The booster has launched from all three of SpaceX’s active pads in Florida and California, including the Crew Dragon test flight in 2019, a mission with three Canadian Radarsat Earth-imaging satellites, SiriusXM’s SXM 7 radio broadcasting satellite, and eight Starlink flights.
Most recently, the rocket launched in Dec. 18 from Vandenberg Space Force Base in California, then landed on a SpaceX drone ship floating in the Pacific Ocean.
When the current version of the Falcon 9 rocket — known as the Block 5 — launched for the first time in 2018, SpaceX officials said the booster could fly 10 times before requiring major refurbishment. After watching how ground teams refurbished and reused Falcon 9 boosters — and running on a record of 119 straight successful Falcon rocket launches — SpaceX is now pushing the limits of the rocket’s life expectancy.
Three Falcon boosters had flown 11 times heading into the Starlink 4-12 mission.
While the Falcon 9 rocket’s first stage returned to Earth for an offshore landing east of the Carolinas, the second stage fired its single engine to reach a preliminary transfer orbit. Another burn about 45 minutes after liftoff placed the Starlink satellites into the proper orbit for separation.
The flat-packed spacecraft deployed from the Falcon 9’s upper stage around 59 minutes after liftoff.
The Starlink satellites will extend solar arrays and use on-board ion thrusters to reach their operational orbit at an altitude of 335 miles (540 kilometers), where they will enter commercial service for SpaceX.
SpaceX has now launched 2,335 Starlink satellites to date, including spacecraft that were decommissioned or suffered failures. More than 2,000 of those satellites are in orbit and functioning as of Saturday, according to a list maintained by Jonathan McDowell, an astrophysicist who closely tracks spaceflight activity.
Read our mission preview story for more details.
ROCKET: Falcon 9 (B1051.12)
PAYLOAD: 53 Starlink satelllites (Starlink 4-12)
LAUNCH SITE: SLC-40, Cape Canaveral Space Force Station, Florida
LAUNCH DATE: March 19, 2022
LAUNCH TIME: 12:42:30 a.m. EDT (0042:30 GMT)
WEATHER FORECAST: 70% chance of acceptable weather; Low risk of unfavorable conditions for booster recovery
BOOSTER RECOVERY: “Just Read the Instructions” drone ship east of Charleston, South Carolina
LAUNCH AZIMUTH: Northeast
TARGET ORBIT: 189 miles by 197 miles (304 kilometers by 318 kilometers), 53.2 degrees inclination
- T+00:00: Liftoff
- T+01:12: Maximum aerodynamic pressure (Max-Q)
- T+02:32: First stage main engine cutoff (MECO)
- T+02:35: Stage separation
- T+02:42: Second stage engine ignition
- T+02:52: Fairing jettison
- T+06:19: First stage entry burn ignition (three engines)
- T+06:39: First stage entry burn cutoff
- T+08:07: First stage landing burn ignition (one engine)
- T+08:29: First stage landing
- T+08:47: Second stage engine cutoff (SECO 1)
- T+45:29: Second stage restart
- T+45:30: Second stage engine cutoff (SECO 2)
- T+1:02:26: Starlink satellite separation
- 145th launch of a Falcon 9 rocket since 2010
- 153rd launch of Falcon rocket family since 2006
- 12th launch of Falcon 9 booster B1051
- 127th Falcon 9 launch from Florida’s Space Coast
- 82nd Falcon 9 launch from pad 40
- 137th launch overall from pad 40
- 88th flight of a reused Falcon 9 booster
- 41st dedicated Falcon 9 launch with Starlink satellites
- 11th Falcon 9 launch of 2022
- 11th launch by SpaceX in 2022
- 12th orbital launch based out of Cape Canaveral in 2022
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Follow Stephen Clark on Twitter: @StephenClark1.