The mission of the Io Orbiter and its lander is study Jupiter's moon Io, both from orbit, and from the surface itself. To get to Io, the orbiter along with its massive booster stage needs to do a fly-by of Venus, followed by two fly-bys of Earth. Upon arriving in Io Orbit, the booster is detached, and the orbiter deploys its instruments. The Io Lander then detaches and begins its decent onto the surface of Io. Once the lander is safely on the surface, and its instruments deployed, the spent booster stage burns the last of its fuel and crashes into the surface, yielding valuable seismic information for the lander. Following the de-orbiting of the booster stage, the Io Orbiter changes its inclination up to 95 degrees to place itself into its final science orbit.
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| Io Orbiter aboard a Delta-IV Heavy at Cape Canaveral | Lift Off | Solid-Stage Booster Separation | Common-Core Booster Separation |
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| Fairing Separation | Stage 1 Separation | Stage 2 Engine Cut-off | Earth Orbit Ejection Burn |
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| Stage 2 Separation | Booster Radiators Deploying | Booster Radiators Deployed | Leaving Earth |
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| Course Correction Burn | Approaching Venus | Approaching Venus | Closest Approach to Venus |
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| Venusian sunset | Sunrise while departing Venus | Closest Approach to the Moon during first Earth Fly-by | Approaching Earth for the first Earth Fly-by |
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| Closest Approach to Earth | Departing Earth | Closest Approach to the Moon during second Earth Fly-by | Approaching Earth for the second Earth Fly-by |
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| Departing Earth | Departing Earth | Approaching Jupiter | Approaching Jupiter |
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| Approaching Jupiter | Approaching Jupiter | Approaching Io, turning for Io Orbital Insertion (IOI) | Approaching Io |
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| Io Orbital Insertion burn | Almost in Orbit | Engine cut-off, in orbit of Io | Booster Stage Separation |
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| Deploying Instruments aboard the Io Orbiter | Instruments Deployed | Io Lander Separation | Braking Burn start |
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| Io Lander Approaching Landing site | Landing Struts Deployed | Approaching Landing Site | Approaching Landing Site |
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| Almost Landed | Touchdown | Io Lander Deploying Instruments | Instruments Deployed |
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| Jupiter from the surface of Io | Booster De-Orbit Burn | Io Orbiter performing an inclination change | Io Lander as viewed from orbit |
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| Jupiter from the surface of Io | Sunset on Io | Jupiter-rise | End of primary mission |