Live coverage of the countdown and launch of a SpaceX Falcon 9 rocket from Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The Starlink 4-21 mission launched SpaceX’s next batch of 53 Starlink broadband satellites. follow us on Twitter†
SpaceX plans to launch 53 more Starlink internet satellites from Cape Canaveral on Thursday. There are two launch options at 9:11 AM EDT (1311 GMT) and 10:30 AM EDT (1430 GMT). The reusable first stage of the Falcon 9 rocket will land on a drone ship in the Atlantic Ocean to complete its 13th flight into space.
The Falcon 9 will head northeast from the Cape Canaveral Space Force Station to deliver the flat broadband relay stations in orbit ranging between 144 miles and 209 miles in elevation (232 by 337 kilometers). The deployment of the 53 flat-packed satellites from the Falcon 9’s upper stage took place approximately 15 minutes after launch.
The launch is the first of five Falcon 9 missions that SpaceX has planned for July. Three more Starlink flights and a Dragon cargo flight to the International Space Station are scheduled for later this month.
With Friday’s mission, SpaceX will have launched 2,759 Starlink Internet satellites, including prototypes and test units that are no longer in service. Friday’s launch marks the 49th SpaceX mission primarily intended to put Starlink internet satellites into orbit.
Stationed in a fire chamber at a launch control center just south of Cape Canaveral Space Force Station, the SpaceX launch team will begin loading supercooled, compressed kerosene and liquid oxygen propellants into the 70-meter-tall Falcon 9 vehicle at T-minus 35 minutes.
Helium pressure medium will also flow into the rocket in the last half hour of the countdown. In the final seven minutes before launch, the Falcon 9’s Merlin main engines are thermally conditioned for flight through a procedure known as “chilldown.” The Falcon 9’s guidance and range protection systems will also be configured for launch.
After launch, the Falcon 9 rocket will send its 1.7 million pounds of thrust — produced by nine Merlin engines — across the Atlantic to the northeast.
The rocket will exceed the speed of sound in about a minute and then shut down its nine main engines two and a half minutes after launch. The booster stage detaches from the Falcon 9’s upper stage, then fires pulses from cold throttle control engines and extends the titanium grid fins to send the vehicle back into the atmosphere.
Brakes twice will slow the missile before landing on the drone ship “Read the Instructions” about 400 miles (650 kilometers) down, about eight-and-a-half minutes after takeoff.
The booster stage that flies Thursday — tail number B1058 — will match SpaceX’s record for most flown Falcon 9 first stage. It debuted on May 30, 2020, with NASA astronauts Doug Hurley and Bob Behnken launching on SpaceX’s first crew flight to the International Space Station. It was relaunched in July 2020 with the South Korean military communications satellite Anasis 2 and also boosted SpaceX’s CRS-21 cargo mission to the space station.
The rocket stage also launched SpaceX’s Transporter 1 and Transporter 3 small satellite rideshare missions and was used on seven previous Starlink missions. Most recently, the booster was launched on May 6 on the Starlink 4-17 mission.
SpaceX has qualified Falcon 9 boosters for at least 15 missions, compared to the previous design time of 10 flights for each Falcon 9 first stage.
The landing of the first stage on Friday’s mission will occur moments after the Falcon 9’s second stage engine shuts down to launch the Starlink satellites into orbit. The separation of the 53 spacecraft, built by SpaceX in Redmond, Washington, is expected at T+plus 15 minutes and 30 seconds.
Retention bars will detach from the Starlink payload stack, allowing the flat-packed satellites to orbit free of the Falcon 9’s upper stage. The 53 spacecraft will deploy solar panels and go through automated activation steps, then use krypton-powered ion engines to maneuver into their operational orbit.
The Falcon 9’s guidance computer is intended to place the satellites in an elliptical orbit with an orbital inclination of 53.2 degrees from the equator. The satellites will use the 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” used in SpaceX’s global internet network. After reaching operational orbit, the satellites will enter commercial service and begin beaming broadband signals to consumers, who can purchase the Starlink service and connect to the network with a SpaceX-provided ground terminal.
ROCKET SHIP: Falcon 9 (B1058.13)
LOAD: 53 Starlink satellites (Starlink 4-21)
LAUNCH SITE: SLC-40, Cape Canaveral Space Force Station, Florida
LAUNCH DATE: July 7, 2022
LAUNCH TIME: 9:11 AM or 10:30 AM EDT (1311 or 1430 GMT)
WEATHER FORECAST: 80% chance of acceptable weather; Low risk of wind at the highest level; Low-moderate risk of adverse booster recovery conditions
BOOSTER RECOVERY: “Just Read the Instructions” drone ship east of Charleston, South Carolina
LAUNCH AZIMUTH: Northeast
TARGET JOB: 144 miles by 209 miles (232 kilometers by 337 kilometers), 53.2 degrees grade
- T+00:00: Launch
- T+01:12: Maximum aerodynamic pressure (Max-Q)
- T+02:27: First stage main engine shutdown (MECO)
- T+02:30: Stage separation
- T+02:37: Engine ignition of the second stage
- T+02:42: Cockpit edging
- T+06:48: First stage entry burn ignition (three engines)
- T+07:08: First stage entry burn cutoff
- T+08:23: First stage landing ignition (one engine)
- T+08:31: Second stage engine shutdown (SECO 1)
- T+08:35: Landing first stage
- T+15:30: Starlink satellite separation
- 162nd launch of a Falcon 9 rocket since 2010
- 170th launch of Falcon rocket family since 2006
- 13th launch of Falcon 9 booster B1058
- 141st Falcon 9 Launch from Florida’s Space Coast
- 91st Falcon 9 launch from pad 40
- 146th launch overall from pad 40
- 104th flight of a repurposed Falcon 9 booster
- 48th Falcon 9 Special Launch with Starlink Satellites
- 28th Falcon 9 Launch of 2022
- 28th SpaceX launch in 2022
- 29th orbital launch from Cape Canaveral in 202
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