Neptune Orbiter with Probes

1. Science Objectives Orbit Neptune, visit all major parts of the Neptune system Cassini-like investigation of the Neptune system Neptune magnetosphere, atmosphere, interior, fields; includes at least two entry probes to different latitudes, 200-bar level Many Triton close(<1000 km) flybys/gravity assists Possible Nereid flyby upon approach Rings & small inner satellites Significant orbit evolution over mission lifetime: ≥ 3-year “Tour”, inclinations up to ~80 deg Neptune Orbiter with Probes Enabling or Enhancing Technologies • Aerocapture systems and software • Sensors and actuators • Aerothermodynamics codes • Thermal protection system (TPS) materials • Validated aeroshell geometries • Aeroshell ground test facilities • Autonomous guidance, navigation, and control software, including orbit propagation • Aerocapture technology flight demonstration; ST-9? • Advanced Radioisotope Power Sources (RPS) • Entry probe systems: TPS, pressure vessels, instruments Mission Description • Gravity assists, possibly with SEP, to Neptune in <13 years • Some trajectories as little as 8 years (JGA, JSGA) • Rigid aeroshell or ballute aerocapture, ∆V > 5 km/s • 2002 study by NASA Aerocapture Systems Analysis Team • Aeroshell mission study in progress • Triton gravity assists yield a Cassini-like tour of the system • This slide’s background shows a fully integrated 2-year tour Measurement Strategy • Cassini-like measurement strategy • Full suite of instruments for measurement breadth and simultaneity • Wide-ranging magnetospheric sampling: lat, long, local time • Large returned data volume • Options with 10 Tbit total return (~4 x Cassini) fit existing LVs ‘03 SSE Survey & ‘02 SEC Roadmap high- priority long-term mission (after 2013); NASA Vision Mission Thomas R. Spilker / Andrew P. Ingersoll 2004/11/16