SpaceX’s Falcon 9 rocket is set for liftoff from Cape Canaveral on Wednesday evening, heading due east over the Atlantic Ocean to deliver the SES 11/EchoStar 105 communications satellite into orbit 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 6:53 p.m. EDT (2253 GMT) Wednesday at the opening of a two-hour launch window.
Perched atop the rocket is the SES 11/EchoStar 105 communications satellite, a spacecraft made by Airbus Defense and Space, ready to beam television programming and video services across the Americas for SES and EchoStar. 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 SES 11/EchoStar 105, SpaceX’s third 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+0:01:18: Max Q
The Falcon 9 rocket reaches Max Q, the point of maximum aerodynamic pressure.
T+0:02:35: MECO
The Falcon 9’s nine Merlin 1D engines shut down.
T+0:02:38: Stage 1 Separation
The Falcon 9’s first stage separates from the second stage moments after MECO.
T+0:02:40: First Ignition of Second Stage
The second stage Merlin 1D vacuum engine ignites for a six-minute burn to put the rocket and SES 11/EchoStar 105 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+0:06:24: 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+0:08:33: 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 SES 11/EchoStar 105 begin a coast phase scheduled to last more than 18 minutes before the second stage Merlin vacuum engine reignites.
T+0:26:59: Second Ignition of Second Stage
The Falcon 9’s second stage Merlin engine restarts to propel the SES 11/EchoStar 105 communications satellite into a supersynchronous transfer orbit.
T+0:27:58: SECO 2
The Merlin engine shuts down after a short burn to put the SES 11/EchoStar 105 satellite in the proper orbit for deployment. The rocket’s computer is programmed to shut down the upper stage engine just before it runs out of propellant, ensuring the payload reaches the highest orbit possible to extend its useful lifetime. The satellite should be injected in an orbit with a high point, or apogee, around 24,300 miles (39,100 kilometers), but the exact altitude depends on the engine’s fuel use.
T+0:36:07: SES 11/EchoStar 105 Separation
The SES 11/EchoStar 105 satellite separates from the Falcon 9 rocket in a supersynchronous transfer orbit.
NASA and Northrop Grumman officials have not set a new target date for the launch of the ICON ionospheric research satellite aboard an air-launched Pegasus XL rocket following a mission abort Wednesday, and it could be weeks before the the long-delayed science probe has another chance to head into orbit off Florida’s east coast.
After 24 days at the International Space Station, SpaceX’s Dragon supply ship came back to Earth on Sunday with more than 5,400 pounds of cargo, human and animal research specimens, and other gear tagged for the trip home. Release from the station’s robotic arm occurred at 5:11 a.m. EDT (0911 GMT), and splashdown in the Pacific Ocean was a few minutes before 11 a.m. EDT (1500 GMT).