Lessons Learned from the 2003 Decadal Survey Andrew Ingersoll




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Solar System Exploration Decadal Survey: Giant Planets

Day 1: August 24, 2009



The following are open sessions

Lessons Learned from the 2003 Decadal Survey

Andrew Ingersoll

The presentation outlined what was learned during the 2003 decadal survey.



Key points from the presentation:

  • Prioritizing the list of promising avenues for flight investigation proved difficult

    • The list that was produced did not take cost into account effectively

  • Having two flagships (Pluto and Europa missions) was not productive

    • It encouraged members of the community to lobby congress directly, as opposed to using the decadal survey process

Nine “Lessons learned” listed in the presentation

  1. Realism and reliability matter, balance cost and science. Good-looking missions will not be successful if their cost balloons.

  2. Leave room for the PI to be innovative. If there is a list of science requirements, NASA can produce an Announcement of Opportunity that has “wiggle room”.

  3. Speak with a unified voice, using the whitepapers as the communities’ input. Lobbying congress in parallel to the survey weakens the process. The mission list from the 2003 survey should be thrown out to leave room for new ideas. The science priority list is still valid however.

  4. Costly missions are good if costs and science are realistic. There should be clear recommendations for each category of mission class.

  5. Continuing missions or missions that are thought to be “in the bag” should also be included in survey report. Don’t take them for granted.

  6. Support ongoing missions and missions under other panels’ jurisdiction.

  7. Spend time writing a list of missions and study the missions.

  8. Primary recommendations list for technology and infrastructure was a good thing. This year the list should be prioritized and include cost estimates. Listed technologies should also be connected to missions. In a midterm report (Grading NASA chaired by Wes Huntress) NASA received a D for New Technology development. A complete list of technologies with priorities could help improve this rating in the future.

  9. Keep the 12 key science questions from 2003. This will reassure the community that there is continuity in the science priorities. Departing from the 12 key questions should come with strong justification.

A discussion of additional lessons:

    • The “P” in JPOP (the concept mission that is planned to fly as Juno) is for probe; probe is not in the technology list because the technology to make the proposed probes was assumed to be available. In reality the technology was “lost” when the heat shield company that made the Galileo probe heat shield closed. Had probe technology been explicitly prioritized, perhaps Juno would still have probes.

    • The lesson is: for every mission proposed, the technology should be known or in the prioritized list of new technology. Otherwise the technology may not be developed and the mission will not fly. Considerations should also be made for technologies necessary for future missions, even if they are further in the future than the next 10 years.

Charge to the Decadal Survey (Joint)

James Green/ Len Dudzinski/Curt Niebur

The survey report should emphasize priorities not expectations and provide recommendations starting with the 2011 fiscal year budget in mind. Delivery of this decadal survey will be in the first quarter of 2011, when NASA will be working on the 2013 budget.

Discussion during and following the presentation


  • Cassini Extended-Extended (also the Cassini Solstice Mission) Mission approval is pending the presidents FY11 budget, expected in February 2010.

  • In addition to the missions outlined on the slides, there is a Russian mission to land on Europa that could be a collaborative mission in the future but currently is solely a Russian mission.

  • Starting in 2018, there will be a plutonium gap, where the demand for plutonium for exploration is greater than the projected supply. Most (but not all) of the plutonium demand responsible for the gap is from manned missions.

  • The limit on plutonium generation is not the neptunium; it is developing a processing method. In the past few years, The Department of Energy (DOE) has not received requests from NASA for fuel. Currently, NASA is and will request plutonium fuel from the DOE, even if manned exploration is scaled back and no longer needs nuclear fuel.

  • The deep space optical communication initiative in its current configuration will not work for the outer planets.

  • Missions should be prioritized even if another agency (e.g. ESA) is taking the lead.

NSF’s Support for the Planetary Sciences (Joint)

Nigel Sharp

The NSF funds many areas of planetary sciences, with the large exception of payloads. They do fund research and laboratory work. The budget of the Astronomical Sciences Division has doubled in the last ten years. In response to an internal review and a decrease in astronomical funding, the Arecibo radio telescope will likely be downsized. The NSF will have to balance the recommendations of this panel and the ASTRO2010 decadal survey recommendations.

Discussion during and after the presentation


  • $60 million a year is awarded for individual research grants from the division of Astronomical Sciences. The total Astronomical Sciences budget is ~$250 million

  • The typical success rate is 20% (but was up to 36% this year because of the stimulus package)

  • Q: Will planetary radar be supported at Arecibo? A: The budget will be reduced, so what is supported will depend on the strength of proposals for facility time.

  • Previous surveys and committee reviews have repeatedly requested to leave the individual research grants budget alone. The result is there is less relative money for facilities.

  • There is only enough funding for one (or two if they are carefully staggered) large astronomy facility projects.

  • If the NSF is spending money in a way that is counter to the wishes of the community or this panel, say so.

  • Nigel Sharp is the primary source for budget and funding information (how NSF is spending money)

OPAG’s Goals and Priorities (Joint)

William McKinnon

A presentation, from the point of view of OPAG, of what the priorities are for exploration of planetary bodies outside the asteroid belt.

Discussion during and after the presentation


  • Very focused scientific objectives could be achieved at Titan or Enceladus by a New Frontiers mission (fly a New Horizons type spacecraft by one or the other), or by spending slightly more than 900 million (the budget for a New Frontier mission). If there was a class of missions between and New Frontier and Flagship classes, the outer planets could benefit a great deal.

  • Probes of the giant planets would provide data that scientists interested in extra-solar planets would be very interested in.

  • Even though OPAG has a list of priorities, they are interested in new ideas, and how they relate to present priorities. OPAG’s listed recommendations and goals are not prioritized.

  • Uranus is left out of the conversation, because it is so difficult to get to the ice giants and Neptune has Triton. By going to Neptune additional science questions can be answered. However, the small icy satellites around Uranus are a class of bodies that are not understood.

Uranus Mission Concept

Mark Hofstadter

An overview of a mission to study an Ice Giant class object; a case is made for a Uranus mission over a Neptune mission.

Discussion during and after the presentation


  • The motivation is to study the class of objects, Ice Giants, not necessarily Uranus. One is not prioritized over the other a priori.

  • The interior structure and magnetic field of Uranus are not well understood.

  • Detailed studies of the rings of Uranus could be accomplished with an orbiter.

  • A Uranus mission has “sales appeal” because we have not studied an Ice Giant before.

  • Launch constraints: if chemical propulsion is used, a spacecraft flying to Uranus needs to be launched in 2018, if solar electric propulsion is used, it can be launched any year.

  • Juno dry mass is 1600 kg, a similar mission could be sent to Uranus (but with less data return)

  • Options exist for solar arrays that can power a Uranus orbiter; the proposed panels would be developed for the manned lunar mission

  • A baseline mission (includes one each: gradiometer and magnetometer) could be built with existing technology, but is not likely scientifically feasible.

  • There is margin in the amount of mass that the mission can handle, because of the flexibility in the propulsion technique (solar electric propulsion)

  • There is a white paper and a full report in the works, both will be made available to the committee.

  • Dollars consistent with 2009 were used in the study.

Cassini Equinox/Solstice Missions and Saturn Science

Linda Spilker

The proposed extended-extended mission (Cassini Solstice mission) will provide new opportunities for answering science questions related to (among other things) Enceladus and Saturn’s rings and atmosphere.

Discussion


  • Saturn proximal orbits would conclude the solstice extension and the Cassini mission by flying very close to the planet (within a hundred thousand km of the cloud tops) and then into Saturn on 15 September 2017

  • The proximal orbits will be very fast but H/He abundances could be measured using stellar occultations.

  • Q: Why end in 2017? A: Fuel will be low enough that planetary protection constraints necessitate a “disposal”. The science potential of the proximal orbits outweighs the potential of waiting for a possible 30-year period storm in 2020.

  • Explaining magnetic field asymmetries is a high science priority for the solstice proposal. Although it is not guaranteed, there is a high probability that the proximal orbits could observe the field in such a way that the asymmetries could be explained

  • Ring age seems to be an important piece of data, if they turn out to be massive that would suggest they are old (primordial). Age does not directly translate into mass, however. With 6 proximal orbits, the radio science people on Cassini think they can determine the ring mass with in 5%.

  • Understanding the fidelity of this method is important if the panel is to make an informed recommendation concerning the Solstice Extended Mission.

  • Of the original 4 reaction wheels, 3 are in use (one was a backup). The backup thrusters are now in use. The team is getting smarter about thruster use, in order for the spacecraft to have power through 2017. New methods for thruster conservation are now in use and are working.

General Discussion

Committee and Guests

  • -Q: are all of the mission concepts that the panel knows about on the agenda? Besides: Io orbiter, Neptune, Probes, JEO, Uranus, Planetary

Other mission concepts include:

PMT:


  • Planetary Monitoring Telescope (PMT) would orbit around Earth and be designed to search for planets. A write up is on OPAG‘s website, it could materialize as a white paper.

  • If PMT was sent to a Lagrange point, it could serve as a technology demonstration for sending spacecraft to gravity wells. This is a potential connection to manned science.

  • The PMT proposal might not be mature enough to take forward.

Ground-based observations:

  • A large gap exists between flagship missions to the outer solar system. Ground-based observations could fill these gaps.

  • If the panel decides to request more ground observation support, it should go to NSF.

  • Because this decadal survey includes recommendations to NSF, if ground based observations are found to be a high priority, they should be included.

  • However, ground-based observations from NSF telescopes rarely occur of Uranus and Neptune.

  • Ground-based observations of Uranus have been beneficial

  • The panel is not able to request more ground-based observation support from NASA. NSF only has limited funds and support history for ground-based observations

Jupiter impact monitoring:

  • Another recent impact suggest there is some scientific potential in monitoring for impacts into Jupiter

  • Amateur astronomers are doing a lot of observational work without any financial backing. The panel could provide some support. Perhaps it would be more appropriate for the small body panel.

Saturn Ring observer:

  • To orbit Saturn above the plane of the rings.

  • This has been studied as part a “Team X” panel

Neptune Orbiter

Multi-probe mission

  • If you can do one, why not multi?

  • A complication is having the right support configuration (orbiter or flyby)

  • Exoplanet science would benefit from in-situ observations. This panel could benefit from a briefing from the exoplanet community. This panel is charged to recommend observation within our solar system that could be useful for the characterisation of exoplanets.

Day 2: August 25, 2009

The following are open sessions

How the TSSM Addresses Saturn Science Goals

Jonathan Lunine

The Titan Saturn System Mission is primarily a Titan observing mission, but it will orbit Saturn for half of its lifetime in the Saturn system providing ample opportunity for Saturn science. There is, however flexibility in the relative orbit times. The spacecraft carries two probes that will be sent into Titan while the orbiter is around Saturn

Discussion


  • The balloon will have periods of proximity to the orbiter when data rate would be high, and periods when data rate is low.

  • From Cassini, the visible image resolution limit (50 m/pixel) of Titan images is a function of the closet approach distance (1300 km from the surface), the detector, and the clouds. TSSM will carry an IR imager that will improve resolution (by looking through the clouds) by 6X.

  • A complete report can be found on the NASA flagship study website: http://solarsystem.nasa.gov/multimedia/download-detail.cfm?DL_ID=402

  • The TSSM study team did not extensively address what the mission could do for Saturn.

  • Its spectrometer will cover 1 to 5.6 micron spectrometer with several times better than VIMS resolution

  • Launch windows from 2017 to 2023 work with this mission if Solar Electric Propulsion (SEP) is used. Windows are more restricted if chemical propulsion methods are used.

  • Radio science system on the TSSM will have both a Ka and X band enabling occultation experiments.

Introduction to the Decadal Survey

Steven Squyres

The survey panels are organized (the solar system is divided) in the same way as the previous survey with the exception of astrobiology. This panel is no longer a standalone, but is now incorporated into each of the other panels. Mission cost estimation studies will occur in parallel with the panel meetings, an important distinction between this and previous surveys. Community interaction is important; each panel member should consider themselves an ambassador to the community. Science should drive what missions are studied. There is no specific allocation of number of studies or amount of money for each panel; but the approximate figure is 3 per panel and $500,000 per study. A science champion (or a team if the added cost is justified) from the panel will be identified for each mission study, in addition to a study scientist from the study center.

Discussion


  • Cost realism is essential for the panel

  • Mission studies and cost estimation are available for immature missions with high-priority. 3 or so per panel, at ~$500,000 per study (approximate numbers)

  • If mission are already very mature, but the panel wishes to make changes to the mission, those recommendations should be made.

  • All missions (regardless of maturity) that are recommended by all of the panels will have cost estimation preformed by an independent company.

  • The panel should start from the science and recommend the missions that best fill the gaps in the community’s current knowledge.

  • The Europa mission will consume funding from the next decade. The panel is asked to provide a recommendation of a suite of missions that fit in the funding box for the next decade.

  • The cost estimate for the Europa mission is 3 billion dollars, with a total budget of 12 billion or so. There is, therefore, enough money for more than one flagship mission if the panel chooses.

  • For the outer planets, missions do not fit into single decades. Technology recommendations are how this panel could enable missions in future decades. Mission studies could be done for missions to be flown in future decades in order to determine the technology necessary to fly the mission.

  • Panels should communicate where there are cross-panel interests.

  • The panel will advise what missions go to APL, JPL, or GSFC, keeping in mind their past experience and their workload. It would be acceptable if the panel requests a mission to be studied by multiple centers.

Science Goals Addressed Via Entry Probes

Thomas Spilker

Probes provide measurements of the composition of giant planets that could help to determine how the giant plants formed, as well as atmospheric pressure and temperature measurements which are essential for understanding planetary dynamics.

Discussion


  • Material for making heat shields is finite. The DOD stopped making it before Galileo, there remains enough to make 2 more of the same size that flew into Jupiter. The facilities to test heat shields have been disassembled and would cost 20 million dollars to reassemble.

  • Heat shields used on Mars or Titan are far too weak to use for a giant (Galileo probe entry speed was ~ 47.5 km/s)

  • From the point of view of the probe science advocates, the order of priority for giant planet probes is: Saturn, Neptune, Jupiter return, and then Uranus. Neptune has a larger internal heat source than Uranus and more carbon monoxide, it is therefore more desirable a target than Uranus.

  • From the point of view of the probe science advocates, the order of priority for giant planet probes instruments address: composition, structure and then dynamics (including lightning).

Neptune mission concept

Candice Hansen

A New Frontiers-class mission is proposed to launch in 2019 and fly by Neptune, Triton and then into the Kuiper belt. Neptune arrival would be in 2029. This would be the first mission to Neptune since Voyager in 1989. Science goals at Neptune concern the rings and their evolution, composition, the atmosphere, magnetosphere, and the satellites. It would use today’s technology for fast development and use nuclear power.

Discussion


  • A decision will have to be made about which Triton hemisphere to observe close up. If Voyager repeat coverage is desirable it will need to be after the Neptune flyby, if the other hemisphere is desirable it would be before closest approach to Neptune. Which KBO is selected will also effect the decision. There are many options.

  • Doing Earth occultation observations depends of a gimbaled high-gain antenna, (Ka band radio). This would be the first experiment to be cut.

  • New Horizons left the KBO off of the primary mission to keep below the cost limit; this mission could use the same approach. Taking it a step further, Jupiter and Saturn science could be left off of the budget (even though there are flybys) for additional cost savings. However the KBO and flybys add a lot to the science. If both are sent for costing, the panel could make an informed decision as to which approach to take.

  • This study has not had the benefit of Team-X; it is simply a science study.

  • This mission would spend several days in the magnetic field but not necessarily be sent down the tail length on it. By selecting a particular latitude flyby, large changes in the magnetic field could be detected (since Voyager).

  • A plasma wave spectrometer is a desirable addition, but doing so would be a departure from the “Be like New Horizons” architecture goal.

TMC Review of Outer Planet Flagship Missions (Joint)

Curt Niebur/Brad Perry

The Jupiter Europa Orbiter (as part of the Europa Jupiter System Mission) was selected over the Titan Saturn System Mission by an independent review by the TMC. The major discriminator between the two was related to mission implementation risk. The Titan Saturn System Mission was determined to have too much implementation risk because completion of the science goals depended too heavily on participation from ESA.

Discussion

Regarding JEO



  • NASA is spending money to study radiation hardening (relevant for the JEO). The panel will have access to the preliminary results. The process will consume 10.5 or more million dollars over 4 or more years.

  • The mission team (JEO) has a plan to address radiation challenges. Their method is to harden each component as opposed to putting the components in a hardened box (as was proposed for Juno).

  • In addition the team has budget for additional costs for unforeseen complications developing radiation hardening.

  • While this approach of hardening instruments means a loss in heritage predictability, the TMC was confident that the JEO team accounted for the added cost.

  • However, the radiation environment is so harsh it is possible that the extra money is inadequate or instrument development could be impossible.

Regarding TSSM

  • TMC only addressed the orbiter portion of the Titan mission (the American portion)

  • Instrument heritage was determined to be problematic for TIRS because the unknowns were not adequately justified or accounted for with budget margin.

  • Titan exploration development will continue. What NASA wants to know from the panel is: what science is the highest priority? Probe? Orbiter?

  • Solar Electric Propulsion was an added complexity, however further technology development will continue.

  • Another hurdle that TSSM had to overcome is the $500,000 that has been spent on Europa mission development. Only limited funds have been dedicated to the other flagship candidates. The panel would like to hear comprehensive numbers on the money invested into the other flagship candidates.

General Discussion

  • ESA also performed an independent review and came to similar conclusions.

  • The panels should consider requesting funding for mission development in preparation for future decades’ flagship missions.

Jupiter-Europa Orbiter and Jupiter Science

Robert Pappalardo

The Europa Jupiter Science Mission (EJSM) includes JGO, ESA’s Jupiter Ganymede Orbiter and JEO, NASA’s Jupiter Europa Orbiter.

Discussion


  • JEO will orbit Jupiter for about 2.5 years, while the minimum, for engineering constraints, is 1.5 years.

  • The Laser Altimeter, on board JEO, will be able to determine the thickness of the ice within 3 weeks of obtaining orbit by looking at the tidal flex.

  • JEO will launch after Juno has finished at Jupiter.

  • 10 degrees of inclination relative to Jupiter is acceptable for the mission

  • The atmospheric science is complimentary to what Juno will accomplish, by focusing on the shallow atmosphere.

  • The benefit over Galileo science is that there will be more data at higher temporal and spectral resolution.

  • The Jupiter system science plan is not very mature. Recommendations from this panel would be very welcome. Jupiter science is a low priority for instrument selection.

  • The reason the Jupiter science is lacking is when the mission planning was started in 2008 a recommendation was made to cut Jupiter science to save on budget. In July, Jupiter science was added back in. NASA HQ would like a recommendation if Jupiter science should remain in the goals.

  • Spacecraft to spacecraft communication could improve the understanding of the orbital dynamics of the Jovian system. There would be tens of opportunities for craft to craft radio-occultations

  • The JEO team has not looked into the potential for adding a Galileo style (300 kg) probe.

  • The JEO team assumed upgrades in the Deep Space Network in their data downlink rates.

Mission Studies and Technical Assistance 1 (Joint)

Paul Ostdiek

The Applied Physics Laboratory (APL) will perform mission studios in the Space Department using a Basic Trajectory Analysis, Preliminary Concept Evaluation, and a Full Conceptual Design. These studies cost 10s or thousands, 50 to 100 thousand, and a few hundred thousand dollars respectively depending on the needed level of analysis. A preliminary study would take 3 weeks or more depending on complexity or iterations, and a full study would produce a product ready for an independent cost estimator.

Discussion


  • A full study would take a few months. APL understands that the panel wants results by December

  • The panel should not worry about the individual workload of the centers. The steering committee will worry about that.

  • The panel will provide a science contact (a “Science Champion”) to interact with the center for the mission study, as a minimum, but if the panel deems it appropriate, it could appoint a science team. Or some middle ground, or combination of panel members or outside persons. The panel has complete freedom to decide what is necessary, however there are limited funds. The NRC does not have money to pay for science team meetings for mission concept studies, and the ultimate responsibility falls to the panel to make recommendations.

  • APL has the flexibility to consider a variety of launch vehicles.

  • The steering committee will be looking at launch vehicles available to the community.

  • APL is comfortable studying any mission concept.

Mission Studies and Technical Assistance 2 (Joint)

Bill Cutlip

Goddard Space Flight Center (GSFC) will perform mission studies in the Integrated Design Center (IDC) that includes an instrument and a mission design Laboratory (IDL and MDL). The IDC can produce studies across a spectrum of maturity levels, and their product is ready for delivery to the independent cost estimator. GSFC is comfortable studying missions from discovery class up to a medium flagship. They are willing to study whole missions or parts (instruments only) and have extensive experience.

Discussion


  • The availability of personnel allows Goddard to start quickly.

  • An intensive study could take from two weeks to a month to complete. Science input is intensive for the first week and less after that.

Mission Studies and Technical Assistance 3 (Joint)

Kim Reh /Robert Moeller/Chet Borden/Keith Warfield

JPL can provide Rapid Mission Architecture (RMA), Team-X, or in-depth level of mission study. Study types increase, respectively, in detail and amount of time and money. An RMA study would take 2 to 5 weeks to explore tens of mission architectures and prioritized based on science, risk and cost (all relative). An X-team study would take a few weeks depending on complexity and determine mass, power, cost, and technology development needs, and produce a report ready for an independent cost estimator. An in-depth study would take 2 to 4 months; provide higher fidelity technical baseline and cost estimates of full missions or parts of missions. They are most appropriate for missions with large amounts of complexity, have high cost (Flagships) or are outside the “family of missions” within the experience of JPL. All studies need a science champion from the panel.

Discussion


  • The concept readiness of the Neptune mission, discussed earlier today, is currently at a Concept Maturity Level (CML) 3

  • Results of the studies performed by JPL are available to the panel.

  • There is a NASA review phase between the JPL study and report delivery to the panel. This is a review mandated by NASA HQ for a sanity check, understanding there is an independent cost review for the panel. This review should take approximately 2 weeks (a TMC light).

  • JPL will standardize the products they will provide to the independent cost review. They need a template from the panel or from the cost contractor to ensure the most appropriate information is provided.

  • NASA is prepared to support 12 to 16 studies.

  • Results from the mission studies should be expected to be between a CML 4 and 5. Even though a CML 4 is expected to be required for the independent cost estimator.

General Discussion (Joint)

  • Q: What is the panel’s expectation for the mission studies? Is it a highly realistic cost estimate? Or detailed feasibility? A: Different missions will have different needs depending on their stage of development.

  • Asking the centers to complete studies on a spectrum of related missions is acceptable but not the same paradigm that the centers are used to.

  • There is a concern that the cost numbers studies generate will be unrealistic.

  • NASA will not release recently submitted proposals. The authors of those proposals will have to submit white papers if they want their missions to be considered.

  • There are many mission studies that have been performed in the past few years. The panel will have to request the information from the center that performed the study.

The remainder of the meeting was held in Closed Session

Acronym List


APL: Applied Physics Laboratory (Johns Hopkins University)

ASRG: Advanced Stirling Radioisotope Generators

CML: Concept Maturity Level

DPS: Division for Planetary Science

DSN: Deep Space Network

EJSM: Europa Jupiter System Mission

EPO: Education and Public Outreach

ESA: European Space Agency

FY: Fiscal Year

GSFC: Goddard Space Flight Center (NASA)

JPL: Jet Propulsion Laboratory

JEO: Jupiter Europa Orbiter

JGO: Jupiter Ganymede Orbiter

KBO: Kuiper Belt Object

MESSENGER: Mercury Surface, Space Environment, Geochemistry and Ranging

NSF: National Science Foundation

OPAG: Outer Planets Assessment Group

PDX: Planetary Dynamics Explorer

R&A: Research and Analysis

RMA: Rapid Mission Architecture (JPL)

TSSM: Titan Saturn System Mission


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