SpaceX’s Falcon 9 rocket is set for liftoff from Cape Canaveral on Monday, heading due east over the Atlantic Ocean to deliver the Koreasat 5A communications satellite into orbit around 36 minutes later.
The 229-foot-tall (70-meter) rocket is poised for launch from pad 39A at NASA’s Kennedy Space Center in Florida at 3:34 p.m. EDT (1934 GMT) Monday at the opening of a 144-minute launch window.
Perched atop the rocket is the Koreasat 5A communications satellite, a spacecraft made by Thales Alenia Space for KTsat, a South Korean company which will use the new telecom relay station to broadcast television, provide Internet connectivity and support maritime services over the Middle East, the Indian Ocean, and broad swaths of Asia, including Korea and Japan.
The timeline below outlines the launch sequence for the Falcon 9 flight with Koreasat 5A.
Data source: SpaceX
T-0:00:00: Liftoff
After the rocket’s nine Merlin engines pass an automated health check, hold-down clamps will release the Falcon 9 booster for liftoff from pad 39A.
T+0:01:10: Mach 1
The Falcon 9 rocket reaches Mach 1, the speed of sound, as the nine Merlin 1D engines provide more than 1.7 million pounds of thrust.
T+0:01:16: Max Q
The Falcon 9 rocket reaches Max Q, the point of maximum aerodynamic pressure.
T+0:02:33: MECO
The Falcon 9’s nine Merlin 1D engines shut down.
T+0:02:36: Stage 1 Separation
The Falcon 9’s first stage separates from the second stage moments after MECO.
T+0:02:38: First Ignition of Second Stage
The second stage Merlin 1D vacuum engine ignites for a six-minute burn to put the rocket and Koreasat 5A into a preliminary parking orbit.
T+0:03:40: 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+0:06:22: Stage 1 Entry Burn
A subset of the first stage’s Merlin 1D engines ignite for an entry burn to slow down for landing. A final landing burn will occur just before touchdown.
T+0:08:32: SECO 1
The second stage of the Falcon 9 rocket shuts down after reaching a preliminary low-altitude orbit. The upper stage and Koreasat 5A begin a coast phase scheduled to last more than 18 minutes before the second stage Merlin vacuum engine reignites.
T+0:08:35: Stage 1 Landing
The Falcon 9 rocket’s first stage booster touches down on SpaceX’s drone ship in the Atlantic Ocean.
T+0:26:45: Second Ignition of Second Stage
The Falcon 9’s second stage Merlin engine restarts to propel the Koreasat 5A communications satellite into a supersynchronous transfer orbit.
T+0:27:52: SECO 2
The Merlin engine shuts down after a short burn to put the Koreasat 5A satellite in the proper orbit for deployment.
T+0:35:38: Koreasat 5A Separation
The Koreasat 5A satellite separates from the Falcon 9 rocket in a supersynchronous transfer orbit.
Virgin Orbit could attempt its first orbital test launch later this month over the Pacific Ocean southwest of Los Angeles, capping a development program for an air-launched small satellite carrier that began in earnest eight years ago.
SpaceX has slowed development of the Falcon Heavy rocket, a mega-booster made of three Falcon 9 booster cores strapped together, as the company recovers from a launch failure last month, delaying the new rocket’s debut until early 2016.
The launch comes as the commercial astronaut mission, Polaris Dawn, is preparing for an on-orbit demonstration of the satellite internet service. Liftoff from Vandenberg Space Force Base happened at 6:45 p.m. PDT (9:45 p.m. EDT, 0145 UTC).
