SpaceX’s Falcon 9 rocket is set for liftoff from Cape Canaveral on Friday afternoon, heading due east over the Atlantic Ocean to deliver the BulgariaSat 1 communications satellite into orbit 35 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 2:10 p.m. EDT (1810 GMT) Friday at the opening of a two-hour launch window.
Perched atop the rocket is the BulgariaSat 1 communications satellite, a spacecraft made by Space Systems/Loral, ready to beam television programming across Bulgaria and neighboring countries in the Balkans. The rocket will place the satellite into a high-altitude “supersynchronous” transfer orbit.
The timeline below outlines the launch sequence for the Falcon 9 flight with BulgariaSat 1, SpaceX’s second launch with a previously-flown first stage booster.
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+0:01:19: Max Q
The Falcon 9 rocket reaches Max Q, the point of maximum aerodynamic pressure.
T+0:02:36: MECO
The Falcon 9’s nine Merlin 1D engines shut down.
T+0:02:40: Stage 1 Separation
The Falcon 9’s first stage separates from the second stage moments after MECO.
T+0:02:47: First Ignition of Second Stage
The second stage Merlin 1D vacuum engine ignites for a nearly 6-minute burn to put the rocket and BulgariaSat 1 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+0:06:19: 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+0:08:31: Stage 1 Landing
The Falcon 9 rocket’s first stage booster touches down on SpaceX’s drone ship in the Atlantic Ocean.
T+0:08:38: SECO 1
The second stage of the Falcon 9 rocket shuts down after reaching a preliminary low-altitude orbit. The upper stage and BulgariaSat 1 begin a coast phase scheduled to last more than 18 minutes before the second stage Merlin vacuum engine reignites.
T+0:27:08: Second Ignition of Second Stage
The Falcon 9’s second stage Merlin engine restarts to propel the BulgariaSat 1 communications satellite into a supersynchronous transfer orbit.
T+0:28:13: SECO 2
The Merlin engine shuts down after a short burn to put the BulgariaSat 1 satellite in the proper orbit for deployment.
T+0:34:55: BulgariaSat 1 Separation
The BulgariaSat 1 satellite separates from the Falcon 9 rocket in a supersynchronous transfer orbit.
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