Follow the key events of the Falcon 9 rocket’s ascent to orbit with the fifth set of 10 next-generation satellites for Iridium’s voice and data relay fleet.
The 229-foot-tall (70-meter) rocket will lift off Friday at 7:13:51 a.m. PDT (10:13:51 a.m. EDT; 1413:51 GMT) Friday from Vandenberg Air Force Base in California.
SpaceX will not attempt to recover the first stage on Friday’s mission.
Data source: SpaceX
T-0:00:00: Liftoff
After the rocket’s nine Merlin 1D engines pass an automated health check, the Falcon 9 is released from Space Launch Complex 4-East at Vandenberg Air Force Base, California.
T+0:01:16: Max-Q
The Falcon 9 rocket reaches Max Q, the point of maximum aerodynamic pressure. The first stage’s nine Merlin 1D engines produce about 1.7 million pounds of thrust.
T+0:02:34: MECO
The Falcon 9’s nine Merlin 1D engines shut down.
T+0:02:37: Stage 1 Separation
The Falcon 9’s first stage separates from the second stage moments after MECO.
T+0:02:39: Stage 2 Ignition
The second stage Merlin 1D vacuum engine ignites for an approximately 6-and-a-half-minute burn to inject the Iridium Next satellites into a parking orbit.
T+0:03:28: Fairing Jettison
The 5.2-meter (17.1-foot) diameter payload fairing jettisons once the Falcon 9 rocket ascends through the dense lower atmosphere. The 43-foot-tall fairing is made of two clamshell-like halves composed of carbon fiber with an aluminum honeycomb core.
T+0:09:02: SECO 1
The Merlin 1D vacuum engine turns off after placing the Iridium satellites in a temporary parking orbit, beginning at 43-minute coast in space.
T+0:52:05: Stage 2 Restart
The Falcon 9’s second stage engine ignites again for an 11-second burn to circularize its orbit.
T+0:52:16: SECO 2
The Merlin 1D vacuum engine shuts down after reaching a target orbit about 388 miles (625 kilometers) high with an inclination of 86 degrees.
T+0:57:16: Begin Iridium Deployments
The 1,896-pound (860-kilogram) Iridium Next satellites begin deploying from their two-tier dispenser on the Falcon 9 rocket’s second stage, separating at intervals of approximately every 90 seconds.
T+1:12:03: End Iridium Deployments
The last of the 10 Iridium Next satellites will separate from the rocket.
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