Europe’s fifth Sentinel Earth observation satellite will ride a four-stage Vega rocket into polar orbit 488 miles (786 kilometers) above Earth to begin tracking changes in agriculture and forestry patterns and monitoring natural disasters.
The ascent will take nearly an hour following launch from French Guiana at 0149:24 GMT March 7 (8:49:24 p.m. EST March 6).
Credit: Arianespace
T+00:00:00 – Liftoff
The Vega rocket’s first stage P80 solid rocket motor ignites and powers the 98-foot-tall booster off the launch pad 0.3 seconds later. The P80 first stage motor generates a maximum of 683,000 pounds of thrust.
T+00:00:31 – Mach 1
The Vega rocket surpasses the speed of sound as it soars on an easterly trajectory from French Guiana. The rocket will reach Max-Q, the point of maximum aerodynamic pressure, at T+plus 53 seconds.
T+00:01:55 – First stage separation
Having consumed its 194,000 pounds (88 metric tons) of solid propellant, the 9.8-foot-diameter (3-meter) P80 first stage motor is jettisoned at an altitude of about 33 miles (53 kilometers). The second stage Zefiro 23 motor will ignite a second later to begin its 102-second firing.
T+00:03:39 – Second stage separation
The Zefiro 23 motor burns out and jettisons.
T+00:03:51 – Third stage ignition
Moving at a velocity of nearly 9,000 mph, or about 3.9 kilometers per second, the Vega rocket’s Zefiro 9 motor ignites for the third stage burn.
T+00:03:56 – Fairing separation
The Vega’s 8.5-foot-diameter (2.6-meter) payload fairing is released as the rocket ascends into space.
T+00:06:32 – Third stage separation
The Zefiro 9 third stage shuts down and separates, having accelerated the rocket to nearly orbital velocity.
T+00:08:23 – First AVUM ignition
The Vega rocket’s Attitude and Vernier Module, or fourth stage, ignites for the first time. The AVUM burns hydrazine fuel with an RD-843 engine provided by Yuzhnoye of Ukraine.
T+00:15:27 – AVUM first cutoff
The Vega’s AVUM fourth stage is turned off after a 7-minute, 4-second burn, beginning a nearly 40-minute coast until the engine is ignited again.
T+00:55:07 – Second AVUM ignition
The AVUM fires a second time for a two-minute burn to put the Sentinel 2B satellite into its targeted orbit.
T+00:57:07 – AVUM second cutoff
The AVUM engine shuts down after reaching a circular orbit with an altitude of 488 miles (786 kilometers), and an inclination of 98.57 degrees.
Loaded with three commercial satellites, a European Ariane 5 rocket returned to its launch pad in French Guiana Thursday after a two-week launch delay to resolve a technical issue that forced an abort to a countdown July 31. Arianespace says the mission has been rescheduled for launch Saturday due to unfavorable upper level winds in the forecast for Friday.
The French government has signaled its intention to sell its stake in Arianespace, a major step in consolidating the European launcher industry under the control of a joint venture formed by Airbus and rocket engine manufacturer Safran.
A Russian Proton rocket rolled out to its launch pad at the Baikonur Cosmodrome in Kazakhstan on Friday, riding a specially-built rail car with Europe’s ExoMars mission bound for the red planet.