Internaonal Planetary Probe Workshop Short Course on Ocean Worlds

June 10-16, 2017

Summary for OPAG 2017-09-07 Kunio Sayanagi (Hampton University) Internaonal Planetary Probe Workshops • Annual Meeng, ~200 aendees • Focus on In-Situ Planetary Exploraon • Short course on planetary science is oen offered with the workshop; • This year’s topic was Ocean Worlds • Various science topics were covered over two days. • Many topics covered (like Mars & small bodies)… à This summary focuses on Outer Planets and Ocean Worlds • Contents are archived at JPL: • hps://solarsystem.jpl.nasa.gov/missions/ippw (2017 meeng contents have not been posted yet) Outer Planets Session Highlights

Conveners: Dave Atkinson (JPL), Kunio Sayanagi (Hampton University), Olivier Mousis (Aix Marseille Université), Bert Vermeersen (TU Del) Session Overview Focused on Outer Planets Missions & Concepts with Atmospheric Probes. Giant Planet Atmospheric Entry Probes form a disnct class of missions, an interest to the IPPW community. • Ice Giants Flagship (Kim Reh) • Addresses a priority of 2013-2022 Planetary Decadal Survey • NASA-funded Science Definion Team Study • Presented overview of mission architecture opons • Hera Saturn Probe (Mousis) • Proposed to ESA M-class Program • Presented Science Case to probe Saturn • SPRITE Saturn Probe (Lobbia+Atkinson) • Proposed to NASA New Froners Program • Presented engineering implementaon of Saturn Probe Session Overview (cont.) • Small Next-generaon Atmospheric Probe: SNAP (Sayanagi) • Mission Concept Study Funded by NASA PSDS3 Program • Presented design overview • Decoding Huygens’ descent dynamics (Lorenz) • Presented analysis of Huygens’ accelerometer to get atmospheric turbulence • Two-staged Saturn Probe for 60-bar Atmos. (Sayanagi) • Mission concept study funded by NASA Langley internal funding. • Separang a deep-stage from a shallow-stage allows reaching water condensaon level of Saturn at 20-bar and deeper Session Highlights

• Excing upcoming opportunies: • NASA is making progress on a Flagship mission to Uranus/Neptune • A priority recommended by the Decadal Survey. • Science Definion Study final report was released this week. • Saturn Probe proposals submied to NASA and ESA • Hera to ESA M-class program (PI: Olivier Mousis) • SPRITE to NASA New Froners Program (PI: Amy Simon) • NASA’s PSDS3 Program funded several entry probe studies • Small Next-generaon Atmospheric Probe (SNAP) to Uranus (PI: Sayanagi)

• Saturn Probe Proposals to NASA and ESA • Demonstrate strong interests in the community

• NASA Funded Mission Studies • Demonstrate agency commitment and community interest to advancing future missions Session Discussion / Interesng Remarks Ice Giant Flagship/Reh: • Aerocapture does not save cost à Aerocapture technology increases payload mass, but the cost saving enabled by aerocapture is not less than the cost of addional payload. à Aerocapture is not necessary to answer the priority quesons idenfied by the decadal survey. Hera Saturn Probe/Mousis: • A Probe that works for Saturn is also viable for Uranus, Neptune and Venus. à Perhaps a common design to serve all mission needs is beneficial. • Hera’s Mass Spectrometer (16 kg) is more massive than Galileo’s 13.2 kg à Hera’s Mass Spec is a Rosea heritage from the University of Bern. à Hera’s Mass Spec has higher mass resoluon. à Galileo Mass Spec would achieve science goals too. SPRITE Saturn Probe / Lobbia+Atkinson: • One in-situ measurement helps interpretaon of remote-sensing elsewhere. • The Cassini orbiter’s final dive will not reach depths where orbiter measurements of upper atmospheric composion and chemistries will benefit entry probe measurements. Session Discussion / Interesng Remarks (Cont.)

SNAP Uranus Probe / Sayanagi: • Carbon Nano-tube based atmospheric composion sensor (NanoChem) does not need a vacuum pump – allows significant mass saving • Carbon Nano-tube mesh is doped with different materials to tune sensivity to different gas molecules Huygens Descent Analysis / Lorenz: • Future Probes should carry 3-axis accelerometer and 3-axis accelerometer to measure probe aerodynamics with higher fidelity Two-staged Saturn Probe / Sayanagi: • Two-staged probe enables deep-atmospheric exploraon

Technology Consideraons Ice Giant Flagship/Reh: • Enabling Technologies: - eMMRTG, HEEET, Doppler Imager Hera Saturn Probe / Mousis: • A Probe that works for Saturn is also viable for Uranus, Neptune and Venus - Mission has high-TRL design, ready for flight - Opened to cooperaon/coordinaon with NASA New Froners Program SPRITE Saturn Probe / Atkinson+Lobbia: - Baery-powered mission without Radioisotope Heater Unit is viable - High-TRL design, ready for flight SNAP Uranus Probe / Sayanagi: - Carbon nanotube-based composion sensor requires environmental tesng. - Solid-state sensors enable significant miniaturizaon of entry probes. Huygens Descent Analysis / Lorenz: • Studies of probe descent dynamics over the past decades enabled improved characterizaon of atmospheric structure from sensor data. Two-staged Saturn Probe / Sayanagi: • Increased mission complexity (second stage) has significant science return.

Highlight Session Discussion • Ice Giant Mission Design • Neptune Mission design was not comfortably closed, so there is room for future studies. • Remarks about the need for Aerocapture and non-RTG- powered missions • Cassini is a good example of a mission that made remarkable achievement with ~10-year extended missions. The extensions wouldn’t have been possible without the RTGs that had large power margins to start with. • Aerocapture would allow increased payload mass, and increased power/mass margin. Aerocapture also enables fast transfer to the targets, so it would increase the mission me at the target. Prime- mission science priories may be achievable without Aerocapture (or RTG) but, without aerocapture, Cassini-like extended missions to the Ice Giants may not be possible. • IPPW-1 discussed small probes enabled by solid-state sensors and approaches for exploring deep atmospheres of the giant planets, so it is nice to see some studies going in that direcon. OCEAN WORDS Conveners: Aline Zimmer (JPL), Andy Frick (JPL), Javier Gómez- Elvira (INTA/CAB) Session Overview

• Strong interests on Europa , Titan and Enceladus.

• Some stascs: • Oral presentaon 11 / Poster 6 • Topics: • Europa 8 / Titan 5 / Enceladus 2 / Technology 2 • Europa lander 6 / Europa missions 2 / Titan mission 1/ Technology for Titan 4 / Technology general 2 / Science 2 • Student presentaons: 5 Session Overview • Europa Lander: • Mission architecture evoluon. Design challenges. Evaluaon of different concepts • Landing site. Importance of a good surface recon images. • Flight system. Design drivers: baeries, de-orbit concept. Planetary protecon • Cruise phase: Clipper experience will be helpful • Touchdown system. Trade-off. Surface adaptaon. Stability requirements. • Surface phase. Operaon concept.

• Other Missions: • Dragonfly. NF Proposal: A rotorcra to explore the Titan dunes. • JEM. A proposal of collaboraon ESA-NASA for the Europa Lander project • Akon. A penetrator as complement for a Europa Lander. Session Overview

• Science • Enceladus and Europa plumes. • Titan geology at laboratory

• Technology • Studies: • Aerobraking simulaons at Titan entry. • Mission trajectory for Enceladus • Roboc entry at Titan • Instrumentaon: Cosmorbitrap: Mass Spectrometer targeng organics • Vehicles. Submarine for Titan sea Session Discussion

• Ocean Words • Many quesons about the Ocean Words are sll opened (see Vision and Voyages for Planetary Science in the Decade 2013-2022). • Water is key for life. Ocean words Exploraon = approach to the origin of life. • OW landing: excing engineering challenges. • New vehicles should be developed. • Lengthy missions – two generaons of sciensts and engineers are required.

• OW should have is own session at the IPPW15.