Venus Bridge: A Smallsat Program Through the Mid-2020s

Transcription

1 Venus Bridge: A Smallsat Program Through the Mid-2020s Robert Grimm (SwRI) James Cutts (JPL) Martha Gilmore (Wesleyan U.) Robert Herrick (U. Alaska) Gary Hunter (GRC) Noam Izenberg (APL) Kandis Lea Jessup (SwRI) Robert Lillis (UCB) JAXA 12 th Low-Cost Planetary Missions Conference Pasadena, CA August 15, 2017

2 Gilmore et al., 2015 Fukuhara et al., 2017 Zhang et al., 2012 Kane et al, 2014 Way et al.,

3 Goals, Objectives, and Investigations for Venus (VEXAG) Atmosphere Surface & Interior System Interactions & Water How did the atmosphere form and evolve? What controls the atmospheric superrotation and greenhouse? What is the impact of clouds on climate and habitability? How is heat released from the interior and has the global geodynamic style changed with time? What are the contemporary rates of volcanism and tectonism? How did Venus differentiate and evolve over time? Was surface water ever present? What role has the greenhouse had on climate history? How have the interior, surface, and atmosphere interacted as a coupled system over time? 3

4 VEXAG Roadmap Earliest US mission will be 35 years after Magellan Near-term ( , now targeting ) Orbital remote sensing Radar imaging, infrared emissivity, gravity, topography VERITAS, EnVISION (all); Venus Design Reference Mission (VDRM: radar, grav, topo); Venera-D (no radar) Sustained aerial platform VDRM, Venus Climate Mission (VCM),Venera-D Deep probe DAVINCI, VCM Short-duration lander VDRM, VISE, Venera-D Multiple probes/dropsondes VCM Fly-by Opportunities VeGASO Roscosmos 4 JPL

5 VEXAG Roadmap Earliest US mission will be 35 years after Magellan Mid-term ( , now targeting ) Multiple deep probes Short-duration tessera lander Long-lived geophysical lander VITAL, NASA Far-term (>2025, now targeting >2040) Surface or near-surface platform with regional mobility Long-lived seismic network Sample return 5 J. Sauder, JPL

6 VEXAG Technology Plan Near-Term, in priority order New thermal protection systems (TPS). High-temperature subsystems and components for long-duration (months) surface operations. Aerial platforms for similar long-duration operations in the atmosphere Deep-space optical communications Mid- and Far-Term, in priority order Advanced power and cooling technology for long-duration surface operations. Advanced descent and landing. Impact of smallsats and cubesats will be assessed in technology & roadmap updates. 6

7 Technical Advances Thermal protection systems Ames HEEET Venus environmental testing facilities Glenn Extreme Environments Rig (GEER) 28 ft 3 steel vessel can accommodate multiple gases to 1400 PSI and 500 C Goddard VICI High-temperature electronics (NASA GRC) 21-day IC demo at Venus conditions Demo of chemical species (multiple), wind, temp, and pressure sensors for targeted 60 day operation No thermal control required for Venus surface Deep-space optical communications Smallsats and cubesats GEER Optical Communications and Sensor Demonstration cubesat 7

8 Venus Bridge: Linking Past & Future US Exploration Over 20 Venus Discovery & New Frontiers proposals : no selections. Venus Flagship is low priority in Decadal Survey. Loss in Discovery 13/14 was particularly disconcerting with 2/5 Venus finalists. VEXAG was directed in Feb 2017 by NASA s Science Mission Directorate Associate Administrator (T. Zurbuchen) to determine if useful Venus exploration can be performed within a $200M cost cap. A Venus Bridge Focus Group was chartered to consider ideas on architectures, technology, and science that could be pursued by one or more small missions launching in the early-to-mid 2020s. The opportunity to study the feasibility of implementing linked missions and demonstrating or developing new technology within the defined cost cap were key aspects of the charter.? 8

9 Relation of Venus Bridge to Planetary Science Deep Space Smallsat Studies (PSDS3) Selections C. Sotin (JPL) V. Cottini (UMD) SAEVe T. Kremic (GRC) J. Cutts (JPL) Venus Bridge considers linked missions and particularly the value of a comm relay. Assess cost savings and greater impact of linked missions compared to individual PSDS3. In order to encompass linkedmission programmatics, Venus Bridge studies are broader with less detail. Avoid specific redundancies with PSDS3 except where timeliness and openness is critical. 9

10 Principal Element Variation Purpose VEXAG Science Goals, Object., & Investig. (GOI) VEXAG Technology Plan VEXAG Roadmap Smallat Concepts PSDS3 Sel. Science Orbiter with Telecom Relay Surface (IR) Atm (IR) Atm (UV) Surface composition & weathering. Does Venus have granites? Is there evidence of recent volcanism or past water? Middle circulation, planetary waves, airglow. How does the atm. circulate? Are there large quakes? Upper circulation & composition. What is the origin of the UV absorber and energy balance of the atm.? II.A.4, II.B.1,2; III.A.2, 3; III.B.2. I.B.1,2,3; II.A.3,4. I.B.2; I.C.1,2,4. Smallsat & cubesat assessment identified for next technol. plan Orbital Remote Sensing VISM VAMOS CUVE Ionosphere Ion escape & precipitation What is the current escape rate of the atmosphere? I.A.2. VISEN Telecom relay greatly enhances data return and hence scientific value of in situ elements. DSOC? Probe Skimmer Atmospheric sample below homopause. Isotopes of noble gases. What is the origin of the atmosphere? I.A.1,2; II.A.2; III.A.1. TPS Deep Probe Cupid s Arrow Descender Profile of atmospheric state and composition. How did the atmosphere form? What is the structure of the atmosphere? I.A.1,2; I.B.1-3; I.C.4; II.A.2; III.A.1,4. TPS Deep Probe DoVe VLAD Aerial Platform Balloon or Airplane Global measurements of cloud-level circulation and composition. Investigate seismicity and interior. Questions mirror probe and lander but global scale. I.A.1,2; 1.B.1,3; I.C.1-4; II.A.2,3; III.A.1, III.B.2,3. TPS, Aerial Platforms Sustained Aerial Platform V. Aerial Platforms Study Grp. Lander Atmospheric & geophysical measurements. Imaging. What is the boundary-layer environment and origin of super-rotation? Is there seismic activity? I.B.1,2; II.A.3; III.B.2-3. TPS, HTE Long- Lived Geophys. Lander SAEVe VLAD 10

11 Focus on Linked Orbital and In Situ Elements Orbiter has robust science potential and least technology development (low risk). provides telecom relay to maximize in situ science return from linked Venus Bridge element and from future missions (infrastructure). In situ vehicles are required to reach critical Venus science objectives (VEXAG & Decadal). provide an opportunity to develop and demonstrate new and improved technology capabilities beyond those used in the 1970s-80s ( cool ) An orbiter and in situ element can jointly advance Venus science and technology in the next 5+ years and achieve the Venus Bridge objectives. 11

12 Perform Two Studies of Linked Orbital and In Situ Elements Orbiter + surface element (lander): GRC / COMPASS Orbiter + atmospheric element (probe or aerial platform): JPL / Team X. The two orbiters will be configured with different strawman instruments. Element linkage as single package, single launch, or separate launches. Delivery to Venus most likely from fly-by or separation from other interplanetary injection Triple Planet Flyby (NASA) Multiple smallsat accommodation on ESPA (DoD STP) 12

13 Conclusion Venus is the cornerstone of comparative planetology and is the key to understanding where Earth-sized means Earth-like elsewhere in the Universe. However, U.S. exploration of Venus has languished. The Venus Bridge study will determine if useful Venus exploration can be performed within a $200M cost cap. Science analysis indicates strong value of small missions; now must determine cost viability. Two studies of linked orbital and in situ elements will be performed. Discussion at VEXAG Annual Meeting in November and delivery of Final Report to NASA in early