Committee on NASA Science Mission Extensions Steven W
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Committee on NASA Science Mission Extensions Steven W. Clarke, Director NAS Keck Center, Washington DC Heliophysics Division February 1-2, 2016 Science Mission Directorate NASA Heliophysics Strategic Goal: Understand the Sun and its interactions with Earth and the solar system, including space weather Solar Terrestrial Solve the fundamental physics mysteries Explorers Probes of heliophysics: Explore and examine the physical processes in the space environment from the sun to the Earth and throughout the solar system. Build the knowledge to forecast space Smaller flight programs, Strategic Mission competed science topics, Flight Programs weather throughout the heliosphere: Develop the knowledge and capability to often PI-led detect and predict extreme conditions in Living With a Star space to protect life and society and to Research safeguard human and robotic explorers beyond Earth. Understand the nature of our home in space: Advance our understanding of the connections that link the sun, the Earth, Scientific research projects Strategic Mission planetary space environments, and the utilizing existing data plus Flight Programs outer reaches of our solar system. theory and modeling 2 2 Heliophysics Mission Portfolio Given the substantial investment the US government makes in these missions, it is prudent and reasonable to maximize the science return on these investments. Over the course of almost 2 decades (starting 1997), NASA Heliophysics has implemented the Senior Review process which calls upon the science community to help assess the scientific productivity and value of missions operating past their original design lifetimes, and provide to NASA, as one of the findings, a rank-ordered list of those missions. This findings have significant input into the future planning of the Heliophysics portfolio, in terms of directing the evolution of the portfolio (i.e. are there physical regimes missing?), and the annual budget allocation. 3 Heliophysics Mission Portfolio • The different classes of missions come with different levels of complexity, scientific capability, and requirements for location in space. These factors will lead to cost differentials, and levels of risk that the Agency is willing to accept. • Larger, more complex missions will be more expensive, and so the Agency will expect broader scientific return, will accept the need to develop new technologies and new capabilities, and will be less risk tolerant leading to additional testing and redundancy requirements. – These correspond to NASA Class A and Class B missions • Smaller, less complex missions will be expected to have more focused scientific objectives and to leverage existing technologies and capabilities; the Agency is more risk tolerant leading to acceptance of selected single-string systems and tailoring of mission assurance requirements. – These correspond to NASA Class C and Class D missions 4 Heliophysics Mission Portfolio Heliophysics missions reflect the primary classes of SMD missions • Strategic Missions – Initiated by NASA generally in response to recommendations in the Decadal Survey – NASA-led strategic heliophysics missions are generally in the large or medium mission class – NASA also initiates strategic partnerships with other space agencies, generally resulting in a NASA contribution to a partner-led mission • PI-led competed missions – Initiated by a PI-led team in the form of an Heliophysics Explorers proposal to NASA, either for a full mission or a mission of opportunity – Helioophysics Explorers full mission classes are small (SMEX) and medium (MIDEX) size – Mission of opportunity classes included contributions to a partner-led mission, small complete missions for the cost of a MO, and suborbital-class missions Examples Full Mission Contribution Strategic MMS, SPP Solar Orbiter Competed ICON, GOLD CINDI, TWINS 5 Heliophysics System Observatory Heliophysics Mission Timeline 1995-2025 Heliophysics Mission Timeline 3 Why Extend Missions? Heliophysics is a field that encompasses a number of sub-discipline areas which are all intimately interconnected: • Solar physics: the processes on the Sun and its extended outer atmosphere (photosphere, chromoshere, and corona) and the kinetics driving these observed phenomena inside the star. The Sun is mildly variable with a periodicity of ~22 years; • Solar wind and the heliosphere: the region between the outer corona and the planets encompassing the entire solar system out to ~121 AU (as measured by Voyager 1) containing all manner and energies of particles, waves, and fields; • The magnetosphere: an extremely complex and dynamic region around the Earth caused by the existence of the Earth’s magnetic field which responds dramatically with solar wind variations; • The ionosphere, thermosphere, and mesosphere (ITM): the upper portions of the Earth’s atmosphere, which also respond to solar wind variations as part of the connection of the Sun to the Earth. The Sun’s 22 year cycle means that phenomena in differing places within this complex, coupled system will look differently depending on where, and when in the solar cycle one observes them. 8 Why Extend Missions? SMD selects missions on the basis of science goals that are important at the time of their selections, whether as a Decadal priority or through a competitive selection. However, almost every mission will produce serendipitous results that were unexpected and which will further our understanding of the physical processes that move the Heliophysics discipline forward, and these discoveries are typically made by missions in extended operations. As an example, Voyagers 1 & 2 were launched in 1977 and after their planetary encounters, were extended by a number of Senior Reviews as they traversed the solar system. The particle, wave, and fields experiments of the two Voyager spacecraft have provided the only in-situ measurements of the outer heliosphere: something never planned in the original mission concept. By extending the missions to the early 21st century, we now have the first-ever measurements of space beyond the heliopause: interstellar space. This could only be accomplished by extending the mission to the present date. 9 Why Extend Missions? Another example, is from the Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) mission which studies the thermosphere, ionosphere and mesosphere of the Earth (the end of the Sun to Earth interaction). It has confirmed the surprisingly fast CO2 increase in the upper atmosphere raising questions of interconnectivity. And while most climate models predict an increase to be roughly equal across the globe, TIMED has observed a faster, preferred increase in the northern hemisphere. Finding such an unexpected trend is only possible because of the 14 years that TIMED has been in operation, as opposed to the original 2 year prime mission. A final example is the simultaneous, full 360o degree view of the Sun by STEREO. Working with SDO, STEREO has enabled, for the first time, uninterrupted observations of an active region on the Sun as it emerges, develops, and decays over several weeks or months. This could only be accomplished during the extended STEREO mission. 10 Why Extend Missions? To place the opportunity costs for the extended operations of the Heliophysics suite of missions in context, in FY16, the entire Heliophysics budget is $640M. The entire portfolio of all operational Heliophysics missions is $108.3M (this includes MMS, which is in its prime mission). If one excludes MMS, then the total for all the extended operating missions is $78.1M. This represents 12% of the entire Heliophysics budget for this fiscal year, or an average investment of $4.6M per mission. Indeed if one were to breakdown the cost per satellite (because some missions have multiple spacecraft involved) the average cost per satellite is even lower, at $2.8M. 11 NASA Heliophysics What fractions of your division’s budget are going towards missions in development, prime phase of operations, and extended phase(s)? FY2016 Heliophysics Budget Research 68,658 11% Development 352,027 55% Prime(MMS) 30,138 5% Operating Missions 78,170 12% Management and Other 19,811 3% Data Systems 19,890 3% Suborbital 71,420 11% Total 640,114 12 NASA Heliophysics Please list the missions currently in operational mission phase. 13 NASA Heliophysics What methods (including any metrics) are in place to review mission performance and what criteria are used to assess prospects for extensions? The reviews NASA carries out for mission extensions (Senior Reviews) take a number of factors into account: Scientific merit; Promise of future impact and Productivity; Progress towards previously agreed-to Prioritized Mission Objectives (PMOs); Impact of past scientific results; Accessibility, usability, and utility of data; Spacecraft and instrument health & safety; Productivity and vitality of the science team; Level and quality of the stewardship of the asset; Effectiveness of communications to the general public. 14 NASA Heliophysics Please describe (briefly) the senior review process currently used by your division to assess operating missions which are candidates for extension. The Senior Review assists NASA in maximizing the scientific productivity from its operating missions within a constrained budget. NASA uses the findings from the Senior Review to: – Prioritize continued funding of the operating missions and projects; – Define an implementation approach to achieve heliophysics strategic objectives; – Provide programmatic and budgetary