| T+00:00 |
Drop |
| The Pegasus XL rocket is released from the Orbital Carrier Aircraft at an altitude of 39,000 feet above the Atlantic Ocean, about 75 miles east of Palm Bay, Florida. |
|
| T+00:05 |
Ignition |
| The first stage solid-fueled motor of Pegasus is ignited to begin the powered journey to orbit with HESSI. |
|
| T+01:15 |
Stage 1 Burnout |
| The Orion 50S XL first stage motor consumes all of its solid-fuel propellant and burns out. A short ballistic coast period begins now. |
|
| T+01:30 |
Stage 1 and 2 Separation |
| The spent first stage motor is jettisoned to prepare for the second stage of flight. The first stage casing falls into the Atlantic Ocean. |
|
| T+01:31 |
Stage 2 Ignition |
| The Pegasus rocket's Orion 50 XL second stage begins firing to continue the trip to orbit. |
|
| T+02:06 |
Jettison Payload Fairing |
| The payload fairing that protected the HESSI satellite during atmospheric ascent is separated once heating levels drop to predetermined limits. |
|
| T+02:43 |
Stage 2 Burnout |
| Having consumed its supply of solid-fuel propellant, the second stage motor burns out. A coast period now begins before releasing the spent stage. |
|
| T+07:23 |
Stage 2 and 3 Separation |
| With its job complete, the Pegasus rocket's second stage is jettisoned from the third stage. |
|
| T+07:34 |
Stage 3 Ignition |
| The solid-fueled Orion 38 third stage ignites to deliver the HESSI spacecraft into the desired orbit around Earth. |
|
| T+08:42 |
Stage 3 Burnout |
| The third stage burns out after using all its solid propellant, completing the powered phase of launch. Orbit insertion has now occurred. |
|
| T+09:42 |
Spacecraft Separation |
| NASA's High Energy Solar Spectroscopic Imager satellite, or HESSI, is released into space from the third stage to complete the Pegasus rocket's 31st launch. |
