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Delta II rocket -- Facts, Info, and Encyclopedia article (Site not responding. Last check: ) |
 | | Deltas are (Click link for more info and facts about expendable launch vehicle) expendable launch vehicles (ELVs), which means they are only used once. |
 | | The medium-capacity Delta II has nine motors total, six of which are lit at liftoff, three lit one minute into flight; the newer Med-Lite models use only three or four motors, all of which are lit at liftoff. |
 | | Stage III: Optional solid rocket motor (some Delta II vehicles are two-stage only, and generally used for Earth-orbit missions) provides the majority of the velocity change needed to leave Earth orbit and inject the spacecraft on a trajectory to Mars; connected to the spacecraft until done firing, then separates. |
| www.absoluteastronomy.com /encyclopedia/d/de/delta_ii_rocket1.htm (356 words) |