OPAG Findings from February 1-2, 2016 meeting in San Antonio

2015 was a good year in the outer Solar System. We celebrated the achievements of New Horizons at Pluto and enjoyed continued success from Cassini. We eagerly look forward to Cassini observations in the new environments that the proximal orbits will explore and anticipate Juno’s arrival and Jupiter orbit insertion this year. These results are based on investments made decades ago.

While we are cautiously optimistic about the distant (>10 year) future given investments being made now for the Europa mission, Ice Giants mission, and Ocean Worlds, we remain very concerned about the coming Decade of Darkness (2018 to ~2028) when there will be no new data from outer Solar System missions, due to minimal investment over the past decade.

The OPAG findings are described below and will be discussed at an OPAG town hall meeting during the LPSC conference, Thursday March 24, 12-1:15 PM.

1. Ocean Worlds Program Jim Green announced NASA’s interest in potentially formulating a new Ocean Worlds initiative, and asked OPAG to initiate a roadmapping study. OPAG enthusiastically supports this idea and has been moving ahead rapidly to form the Roadmaps to Ocean Worlds (ROW) team. Over 35 leading scientists have responded (so far) to the request for participants. The OPAG committee has carefully considered who should be the co-chairs to lead ROW, and have selected Dr. Amanda Hendrix (PSI) and Dr. Terry Hurford (GSFC). These co-chairs will proceed to select topical leads and schedule a series of meetings, mostly via telecons/webex. We request NASA support for logistics: setting up telecons, paying for limited travel needs, and publishing a final report or paying journal page charges to publish the report or set of reports. The ROW team will present their preliminary findings at the next OPAG meeting in summer 2016.

Finding: OPAG enthusiastically supports the Ocean Worlds program initiative and the roadmapping effort, and requests logistical support from NASA for ROW.

2. FY16 Budget OPAG is thrilled by the increase of the planetary science budget in FY16 and the interest in the exploration of ocean worlds. This budget secures the ongoing activities for the Europa mission and provides additional funding for technologies needed for planetary missions, including those needed for satellite surface technologies. We were very pleased to hear Jim Green affirm that the R&A budgets will rise along with the overall PSD budget.

Finding: OPAG is pleased by the FY16 budget and the expectation of increased funding for R&A.

3. Deep Space Network The DSN, responsible for communicating with both U.S. and international planetary missions, is an absolutely vital support infrastructure without which we can’t have missions beyond the Earth system. OPAG is extremely concerned about the DSN organization’s response to budget cuts and urges PSD to step in quickly to rescue the DSN. The DSN issues have already affected outer planet missions and scientists are losing data because of them. For example, at the end of January, in the days around Cassini's second largest maneuver in 2016, the Cassini team had a difficult time uplinking, verifying and tracking the maneuver. Subsequently they lost a tracking (and data) pass and the prime pass for a Titan approach maneuver, forcing them to use the backup pass to finish targeting a critical flyby in their inclination-raising campaign. Not only does this situation threaten return of science data, it also poses a risk to the successful execution of the Cassini and Juno missions. It is absolutely critical to Cassini’s Grand Finale and to Juno’s prime mission that they manage their trajectories very carefully. A missed maneuver, an error in their gravity assists, or a lost critical tracking pass can quickly eat away at their remaining propellant, already extremely low in the case of Cassini. There will be more near-term impacts, including the reduction of performance below the guaranteed levels (e.g. 95% proficiency for telemetry). Drastic reductions could come in future years when we see the real impacts of the reduction in maintenance and technology funding. OPAG requests an update on this situation at or before the PSS meeting in early March.

Finding: It is imperative that current DSN capabilities be maintained and OPAG requests an update on this situation by the next PSS meeting.

4. Europa Mission The FY16 budget provides robust funding for the Europa mission, and directs that the mission be launched on an SLS in 2022 and that a lander be included with this mission. OPAG strongly supports the multiple flyby mission but is concerned about potential delay to the arrival of this mission at Jupiter. Addition of a lander could delay launch past 2022 and further delay arrival because a gravity-assist trajectory would be needed to deliver the extra mass to Jupiter. A major concern to OPAG is the coming Decade of Darkness (2018 to ~2028) when there will be no active spacecraft in the outer Solar System. This Decade of Darkness will end with the arrival of the Europa mission, so we do not want to see this delayed for any reason.

Finding: OPAG strongly supports the Europa multiple flyby mission and urges NASA to remain committed to its earliest possible arrival date at Jupiter.

5. Radioisotope Power Systems (RPS) The news that DOE has produced a 50-gram demonstration batch of Pu-238 using production processes and equipment is a significant achievement for the exploration of the outer Solar System and its ocean worlds. OPAG lauds the tenacity of PSD and DOE to achieve this advance. OPAG is also appreciative of the opportunity to use RPS on the next NF mission and encourages PSD to offer RPS as government furnished equipment (GFE) in future Discovery mission opportunities. We also encourage PSD to support the development of technologies leading to more capable RPS beyond the current MMRTG. One obstacle is the degradation over time that strongly limits the power available once at the target body, particularly after a long cruise time. OPAG urges PSD to support developments to enable the end-of-mission power levels needed for outer planet science missions.

Finding: OPAG notes the significant progress being made in the area of RPS. OPAG urges PSD to rapidly advance RPS systems to enable the end-of-mission power levels required for outer planet science missions.

6. The Legacy of Cassini and Cassini Data Analysis Program (CDAP) Cassini’s data return from the Saturn system continues to inspire, captivate and scientifically challenge us. During its final year, the Cassini Grand Finale Mission will produce many hundreds of gigabits of fundamentally new data, including unique near-field gravity measurements, novel in-situ sampling of atmospheric constituents, ring particles, and magnetic fields and plasmas. The Cassini Data Analysis Program (CDAP) has funded much groundbreaking research from the data collected by Cassini. OPAG is very pleased that NASA plans to continue the CDAP program after the conclusion of the Cassini/Huygens Mission. We are concerned that to accommodate the need to analyze Cassini’s wealth of unique new data at the end of the mission the normal level of support for the CDAP program may be inadequate. The wealth of new data collected at the end of the Cassini mission will require time and resources to analyze completely.

Finding: Continuation of CDAP will help to bridge the large gap before the next outer Solar System mission and ensure that a knowledgeable cohort of outer planet scientists will be ready to analyze data from the Europa mission, as well as other future outer planet missions. We encourage PSD to monitor the selection levels and be prepared to augment CDAP if needed in the future.

7. Ice Giant mission study for the next Decadal Survey OPAG is very pleased that the Ice Giant mission study (announced at the OPAG meeting in August 2015) is progressing. In particular, we note the recent selection of the Science Definition Team (SDT), the inclusion of international members, and the fact that the science community is being engaged. We also note the strong community response to the opportunity to serve on the SDT. OPAG thanks NASA PSD for this effort, which addresses ice giant recommendations in the past two planetary science decadal surveys. We also thank NASA PSD for responding to concerns raised about the previous Decadal Survey by starting mission studies early and allowing for cost reconciliation between the lead NASA center and the independent cost assessment. OPAG will request updates on ice giant missions and technologies at its next meeting.

Finding: OPAG is pleased with the selection of a Science Definition Team for the Ice Giant pre-decadal mission study, as well as the study’s ground-rules. We encourage rapid progress on identifying candidate missions and supporting technologies.

8. New Frontiers We are pleased that work is progressing to release a New Frontiers 4 AO in early 2017. A recent community announcement stated that Ocean Worlds (i.e., Titan and Enceladus) will be added to the New Frontiers mission concepts list for the 2017 AO. Jim Green stated this decision was based on recent discoveries of very high science value, and that adding Ocean World targets was thus exercising the “New innovative mission concepts” option from the 2008 NOSSE Report: "Opening New Frontiers in Space: Choices for the Next New Frontiers Announcement of Opportunity " http://www.nap.edu/catalog/12175/opening-new- frontiers-in-space-choices-for-the-next-new. OPAG agrees that habitability of Titan and Enceladus should be high-priority objectives for New Frontiers. OPAG is concerned that the cadence of New Frontiers AOs (7 years between NF-3 and NF-4) suggests that the NF-5 AO will not be released before 2023, the end of the current Decadal Survey, effectively orphaning the NF-5 mission candidates

Finding: Based on the newest results for Titan and Enceladus from Cassini, OPAG supports the inclusion of Ocean Worlds in New Frontiers, and urges NASA to strive to release the NF-5 AO before 2023.

9. Discovery Program OPAG supports a robust and continued Discovery Program that welcomes a diverse set of missions, including those to outer Solar System targets, consistent with the congressional recommendation for Ocean Worlds. We support the return to the cadence of five missions each decade as recommended in the Decadal Survey. One option for achieving this cadence is to pick 2 missions each opportunity with opportunities available every 4 years. OPAG also encourages use of technologies that NASA continues to invest heavily in, such as radioisotope power sources (RPS), which enable missions to more diverse targets within the Solar System (particularly in the outer Solar System). However, past mission studies have shown that it is not feasible to execute these missions if the costs of the RPSs are within the PI Managed Mission Cost cap for Discovery. In order for NASA to reap the benefits of its significant sustained investment in RPS it is critical that RPSs be offered as Government Furnished Equipment (GFE) for Discovery flight opportunities. Failure to do so makes RPS use on Discovery missions extremely unlikely and eliminates many exciting missions from the program.

Finding: OPAG recommends the cadence of five Discovery missions every decade and the inclusion of RPS as GFE within the Discovery Program.

10. Participating Scientist Programs Separate from mission or instrument-defined support for students and postdocs, participating scientist programs (PSP) make it possible for new people to become involved directly in missions and to gain valuable mission experience. These programs have been demonstrated to be an effective means of providing experience to younger members of the community and increasing the diversity of teams, while simultaneously enhancing mission science return. Valuable mission experience can include being directly responsible for measurement planning (e.g., Mars rovers), being involved in the decision process that informs the measurement planning (e.g., Cassini) or helping collect mission data and lessons learned for End-of-Mission tasks. PS involvement brings value to the team, the PS investigator, and the resulting science from the opportunity to network with the personnel who have been involved since instrument or mission selection. This is especially valuable when considering outer Solar System missions, given long mission durations. These interactions cannot be reproduced within data analysis programs. A PSP expands the pool of well-qualified and experienced mission team members, helping to widen the narrow pipeline of "qualified" investigators. Having NASA-selected PSs, with input from the original team to identify mission needs, reduces the potential of selection bias. Beyond PSPs, which can include junior personnel, there is also need to support postdocs and students on missions, not only as training opportunities and chances to diversify mission involvement, but also to maintain sufficient staffing to produce excellent science. Both PS and early career support are critical components of missions. With rising mission budgets, and yet dwindling phase E and F budgets that support scientists, NASA and its missions are at risk of losing talent that is essential to mission success.

Finding: We encourage NASA to consider broader use of participating scientist programs and early career mission support. At NASA’s request OPAG (working with other AGs) will lead a white paper providing more detailed information to NASA about the importance and effectiveness of such programs.

11. International Collaboration We thank NASA for initiating the HISAKI Guest Investigator program and for including foreign scientists on the Ice Giants SDT. We also note that ESA’s JUICE mission has tremendous synergy with the Europa mission, and urge more coordination between these communities.

Finding: NASA should facilitate cooperative activities with foreign-led missions whenever appropriate.

12. CubeSats CubeSats are excellent options for demonstrating technologies for planetary exploration and provide a pathway to increasing science data return by reducing costs through miniaturizing spacecraft and instruments, which is critical for outer planet missions. CubeSats also engage and provide flight experience for young engineers and scientists, often beginning when they are still in academic environments.

Finding: OPAG encourages PSD to continue development of CubeSats and small instruments for planetary exploration.

13. Astrophysics Assets for Outer Planets Research OPAG notes Jim Green’s announcement of the new “Astrophysics Assets for Planetary Science” website (http://www.lpi.usra.edu/astrophysicsassets/). Jim and others at OPAG noted that Hubble Cycle 24 and Kepler Extended Mission (K2) deadlines are approaching (see aforementioned website). Jim also noted that James Webb Space Telescope is on track for its 2018 launch and that an issue of PASP is devoted to Solar System science with JWST (see http://www.stsci.edu/jwst/science/solar-system). OPAG also heard a presentation from Professor Walt Harris about studies of future large ultraviolet/optical/infrared space telescopes, with specific examples of such a facility’s capability for the outer Solar System.

Finding: Current and future astrophysics assets are excellent tools to conduct remote sensing in the outer Solar System, and we encourage the continued engagement of the planetary science community in the development and operation of these missions.

14. New Frontiers Data Analysis Program The question was posed to OPAG as to when NFDAP proposals should be due. The consensus was that the due date should be after the second New Horizons PDS data release, which is slated to be much larger than the first release. Including this second PDS release leads to a mid-November proposal due date, with the request to please avoid the same deadline as other programs.

Finding: OPAG prefers that that the New Frontiers Data Analysis Program proposals be due after the second release of New Horizons data by the PDS.