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H-2A/Akatsuki launch timeline
Posted: May 16, 2010
Updated: May 19, 2010

NOTE: Launch sequence data assumes liftoff on May 20, 2010.

T-00:00 Liftoff
With its LE-7A main engine and two solid rocket boosters firing, the 174-foot-tall H-2A rocket lifts off from the Yoshinobu launch complex on Tanegashima Island. A few moments later, the rocket will complete a pitch program to head east from the launch site.
T+01:55 SRB-A Burnout
The H-2A's two solid rocket boosters exhaust their propellant and burn out at an altitude of 32 miles.
T+02:05 SRB-A Separation
The two solid rocket boosters are jettisoned.
T+04:19 Fairing Separation
After traversing the dense lower atmosphere and reaching an altitude of 91 miles, the rocket releases the 4-meter (13.1-foot) diameter payload fairing protecting the spacecraft during the early part of the flight.
T+06:29 Main Engine Cutoff
After consuming its liquid hydrogen and liquid oxygen propellants, the LE-7A first stage main engine shuts down. The first stage and solid rocket boosters push the rocket to a velocity of about 11,400 mph.
T+06:37 Stage Separation
The H-2A rocket's first stage is separated now, having completed its job. The spent stage will fall into the Pacific Ocean downrange from Tanegashima.
T+06:43 Second Stage Ignition 1
With the first stage jettisoned, the rocket's second stage takes over. The LE-5B hydrogen-fueled engine ignites at an altitude of 140 miles to accelerate the payloads to orbital velocity during its first of two burns.
T+11:29 Second Stage Cutoff 1
The LE-5B second stage engine shuts down after reaching its specified orbital targets. This completes the first burn of the second stage.
T+12:32 Negai Separation
The 2-pound Negai CubeSat payload will be deployed in a low-altitude parking orbit for Soka University of Japan. Negai will test an information processing system during a three-week mission.
T+12:42 WASEDA-SAT2 Separation
The WASEDA-SAT2 seconday payload separates from the H-2A upper stage. Developed by Waseda University, the 2.6-pound spacecraft will conduct technology experiments in orbit.
T+12:52 KSAT Separation
The 3.3-pound KSAT spacecraft is released from the H-2A upper stage to conduct Earth observation experiments for Kagoshima University.
T+22:32 Second Stage Ignition 2
After coasting for more than 11 minutes, the H-2A rocket's second stage LE-5B engine fires again to propel the Akatsuki spacecraft on an escape trajectory.
T+26:23 Second Stage Cutoff 2
The LE-5B second stage engine shuts down after reaching an escape trajectory at a velocity of approximately 26,000 mph.
T+27:27 Akatsuki Separation
The Akatsuki spacecraft separates from the H-2A upper stage to begin a six-month journey to Venus.
T+32:27 Begin Solar Array Deployment
Akatsuki's two solar array paddles begin deploying about five minutes afer spacecraft separation.
T+35:27 End Solar Array Deployment
The solar array paddles should be fully unfurled eight minutes after spacecraft separation.
T+35:47 Payload Attach Fitting Jettison
The payload adapter connecting the Akatsuki and Ikaros spacecraft is released, exposing the Ikaros solar sail for separation.
T+42:42 Ikaros Separation
The H-2A rocket's secondary payload, the Ikaros solar sail, separates 43 minutes after liftoff.
T+47:52 UNITEC-1 Separation
The 46-pound UNITEC-1 satellite from the Japanese University Space Engineering Consortium is deployed. UNITEC-1 will test computer technologies and broadcast radio waves from deep space for decoding by amateur radio operators.

Data Source: JAXA/ISAS