NASA has begun to explore its options in light of both the Decadal Survey's recommendations and its new reduced budget outlook. One way to stretch dollars is to share a ride with a partner, in this case the European Space Agency. NASA already had arrangements in place with ESA to cooperate on two missions, the Europa Jupiter System Mission and the 2018 joint Mars rover mission. NASA's new budget outlook makes the scale of previously planned the U.S. contribution to those missions impossible. As a fall back, NASA will honor its agreement to supply up to five instruments to ESA potential Jupiter Ganymede Orbiter. The U.S. agency will also seek to redefine the Mars mission in conjunction with ESA to enable the mission to fly with a U.S contribution of up to $1B (which is approximately the planned European contribution).
Editorial Thoughts: If current plans hold, the next decade will see several moderate sized planetary missions fly: ESA's BepiColombo Mercury orbiter (with a Japanese sub-satellite), a Russian Venus mission, three NASA New Frontiers missions, ESA's Jupiter Ganymede Orbiter if selected as the next large science mission, and potentially a 2018 ESA-NASA Mars rover. It's difficult to compare costs between missions because of different accounting rules. Including spacecraft, instruments, operations, and launch, however, these missions would range from approximately $1B (the next NASA New Frontiers mission) to perhaps $2B (ESA and NASA's contribution to a 2018 Mars rover mission). These costs are a big step back from past flagship missions like Galileo and Cassini that might in today's inflated dollars cost $4B+.
ESA and NASA are now planning missions of comparable scale. Cooperation can allow more capable missions than either could do alone. NASA's contribution of up to five instruments to JGO might represent half the instrument compliment and 10-20% of the mission costs.
Cooperation can also be made difficult by differing goals. For the 2018 mission, ESA has as core goal developing and demonstrating rover technology. It also has a kick-ass instrument compliment for analyzing samples drilled from up to two meters below the surface. The design of ESA's rover is almost complete. NASA has the goal to collect and cache samples for future return to Earth. The requirements include sampling a variety of rocks and soils, which is likely to require a sophisticated robotic arm along with the sample handling hardware. Conceptually, the arm and sampling handling system could be "bolted" on to the ESA rover. In reality, merging high tech systems that must survive launch, cruise, and operation on Mars means that this could be a complicated redesign.
One basis for a cooperative mission might be a redesigned rover that hosts the subsurface drill, the instrument compliment, a sampling arm (probably with some instruments of its own), and the caching system. NASA could provide the entry, descent, and landing system derived from the Mars Science Laboratory mission that would allow precision landing into the most scientifically interesting sites. NASA could also provide the launch. Such a mission might have approximately equal financial contributions by both nations. The devil, however, will be in the details of design, financing, and meshing goals.
To provide additional background on the issues from NASA's perspective, I'm reprinting a portion of the notes from this week's meeting of the Planetary Society Subcommittee meeting. The quotes come from the meeting notes and NASA's director of Planetary Science presentation. You can download both at http://www.lpi.usra.edu/pss/.
From the Notes:
A back of the envelope calculation suggests that after accounting for the higher priority elements (R&A, technology development, Discovery, and New Frontiers), we will have about $1B between now and 2018 to discuss a Flagship. This is nowhere near what even the recommended descoped MAX‐C will cost. Sanjay Limaye asked if that $1B includes launch costs, to which Jim responded that it does if we launch it (as opposed to ESA or another partner).
In response to a question from Mini Wadhwa on how MAX‐C [NASA's proposed rover for the 2018 mission] might be descoped, Jim replied that our first step will be to go back and talk with ESA, starting with a clean sheet of paper to see if we can build a joint Mars mission that meets both our needs and theirs within a budget both sides can afford. John Grant asked whose requirements would be used to develop the new mission, Jim noted that ESA has certain technology development needs and we have requirements on our side, sample caching in particular, that will all need to be addressed. Discussions on this front already began at LPSC and they will continue in earnest at the NASA/ESA bilateral on March 30th ‐ 31st.
Mark Sykes asked what would happen if there is no viable flagship option. Jim responded that the decision‐making rules for Flagships are clearly laid out in the decadal. The emphasis is placed on a balanced program. Flagships provide an enormous science per $ value. There are opportunities to move forward by partnering in the international arena, we need to carefully explore those options, then, and only then can we say no flagship.
Jim noted that at the NASA/ESA bilateral, we will reconfirm our commitment to support ESA’s Laplace mission (Jupiter Ganymede Orbiter), should it be chosen. The PSS also confirmed their support for Laplace and for working with ESA in general. Jim Slavin asked when ESA might make a decision about the Laplace mission. Jim Green noted that ESA will not make a down‐select for their L‐class mission anytime
soon, they are putting together Science Definition Teams to explore what ESA‐only missions might look like, and it will take about a year for those studies to complete.
In response to a question from Bill McKinnon, Jim noted that for the time being, PSD is not undertaking a cost exercise to look at a descoped Jupiter Europa Orbiter. There has been no discussion of how to get a useful Europa mission for ~$1B. In response to a question from Julie Castillo about the future of the JEO community, Jim stated that from a US perspective, the JEO SDT [Science Definition Team] has been thanked and disbanded; any new discussions will be in concert with ESA.
From James Green's presentation:
- Determine if Mars 2018 can be accomplished starting with the minimum set of requirements and “a clean sheet of paper” as Planetary’s top priority flagship mission
- Reaffirm NASA’s commitment to support ESA’s Laplace mission if it is chosen as the CV‐Large class mission
- Up to 5 (as budget allows) of the scientific instruments on JGO as a Mission of Opportunity and support for their PI‐led teams
- Support for Interdisciplinary Scientists
- A NASA Project Scientist to co‐chair the international Project Science Group (PSG) with ESA Project Scientist
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