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.
An Indian Polar Satellite Launch Vehicle blasted off and successfully deployed a military electronic surveillance satellite and 28 nanosatellites for companies in the United States, Lithuania, Spain and Switzerland at two different altitudes Monday, before the rocket’s upper stage began an extended mission as a solar-powered experiment platform in low Earth orbit.
NASA is moving forward with a crucial test-firing of the core stage of the first Space Launch System heavy-lift rocket as soon as Jan. 17 after engineers were satisfied with the results of a fueling test last month.
While recovery teams continue combing through the test site at Cape Canaveral where SpaceX’s first space-worthy Crew Dragon capsule was destroyed in an explosive accident last month, engineers a few miles away are pressing ahead with the company’s 17th resupply mission to the International Space Station set for launch early Friday.