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.
Rocket Lab’s second Electron booster lifted off from New Zealand’s North Island on Saturday, U.S. time, and reached orbit after an eight-minute climb over the Pacific Ocean. Liftoff with three commercial CubeSats occurred at 8:43 p.m. EST Saturday (0143 GMT; 2:43 p.m. New Zealand time Sunday).
A European environmental satellite launched Tuesday from Russia’s Plesetsk Cosmodrome to begin a mission of at least seven years measuring the height, color and temperature of the world’s oceans. The Sentinel 3A spacecraft lifted off aboard a Rockot booster at 1757 GMT (12:57 p.m. EST).
