Appendix C

Input from NASA and the Community

The following input from NASA and the community is provided, unedited, in this appendix:

INPUT FROM NASA

Paul Hertz

INPUT FROM THE COMMUNITY

Kevin France

James C. Green

Jack Burns

Pete Roming

Stephen Unwin

INPUT FROM THE SMEX PRINCIPAL INVESTIGATORS

Fiona A. Harrison

Alan Title

Martin C. Weisskopf

INPUT FROM NASA

Paul Hertz
February 27, 2017

Statement of Question:

• Is there still sufficient compelling science in a SMEX-sized mission to justify a SMEX AO in 2018 or 2019 (note we received MIDEX proposals in 2016, they are under review now, so a SMEX AO is next)?
• SMEX is defined by two things: (i) cost cap (was $125M in 2014 AO) and (ii) launch capability, which is Pegasus-class rather than a Falcon 9/Antares class (note there are other small LVs being developed that might compete with Pegasus in the future).

Based on the February 7, 2017, telecon, NASA agreed to provide the following data to the CAA:

1. List of all SMEX Phase A studies that we have conducted, with some basic info
2. Links to any open information on missions that were proposed but not selected. (Some PIs present their proposed missions at conferences, or post a paper on arxiv.)
3. Publication records for launched missions. The only successfully launched astrophysics SMEX missions are SWAS, GALEX, and NuSTAR.
4. A statistical (anonymous) analysis of proposed SMEX missions vs science grade vs TMC grade. (Not sure what this will look like, this will take some thought on our part.)

NASA POCs

• Paul Hertz (paul.hertz@nasa.gov)
• Linda Sparke (linda.s.sparke@nasa.gov)

1. List of all SMEX Phase A studies that we have conducted, with some basic info

Early SMEX missions, selected with a one-step AO (no competitive Phase A studies)

• SWAS (Submillimeter Wave Astronomy Satellite)
  • PI: Gary Melnick, Smithsonian Astrophysical Observatory
    • Selected April 1, 1989 (from Wikipedia)
    • Launched December 6, 1998
    • Mission completed July 21, 2004 (result of Senior Review)
    • Mission reactivated June-August 2005 to support Deep Impact
  • Mission homepage: https://www.cfa.harvard.edu/swas/swas.html
  • Data archive: http://irsa.ipac.caltech.edu/applications/SWAS/
  • Wikipedia: https://en.wikipedia.org/wiki/Submillimeter_Wave_Astronomy_Satellite
• WIRE (Wide Field Infrared Explorer)
  • PI: Perry Hacking (Jet Propulsion Laboratory)
    • Selected
    • Launched March 5, 1999
    • Premature ejection of telescope cover shortly after launch resulted in mission- ending loss of cryogen (https://www.nasa.gov/pdf/384167main_WIRE_case_study.pdf)
  • Data archive: http://www.ipac.caltech.edu/wire/
  • Wikipedia: https://en.wikipedia.org/wiki/Wide_Field_Infrared_Explorer

1997 SMEX AO, selected a primary mission (GALEX) and a backup mission (BOLT). Both completed Phase A studies. After GALEX successfully passed into Phase B, the BOLT study was terminated.

• GALEX (Galaxy Evolution Explorer)
  • PI: Chris Martin (Caltech)
    • Selected: October 16, 1997
    • Launched: April 28, 2003
    • NASA funding ended: February 2011 (result of Senior Review)
    • Mission completed: February 12, 2012 (operated for one year on private funding)
  • Mission homepage: http://www.galex.caltech.edu/
  • Data Archive: http://galex.stsci.edu/
  • Wikipedia: https://en.wikipedia.org/wiki/GALEX
• BOLT (Broadband Observatory for Localization of Transients)
  • PI: Charles Hailey (Columbia U)

1999 SMEX AO was the “TMC-lite” experiment. Proposals were not required to include mission implementation (technical, cost, schedule) data. Step 1 selections were based on science only, but there was no way to assess whether the mission could be done within the SMEX cost box. The experiment was considered a failure (). Five astrophysics proposals were selected for Phase A studies; after evaluation of Phase A Concept Study Reports, SPIDR was downselected to proceed into Phase B. One mission proposal (Joule, PI Richard Kelley, GSFC) was converted into a Mission of Opportunity contribution to the Japanese Astro-E2/Suzaku mission.

• Description of Phase A study missions: https://www.hq.nasa.gov/office/oss/codesr/smex/smex99/descriptions.html
• SPIDR (Spectroscopy and Photometry of the Intergalactic Medium’s Diffuse Radiation)
  • PI: Supriya Chakrabarti (Boston U)
    • Selected: September 13, 2000
    • Downselected: July 2, 2002
    • Terminated: May 2003 (the SPIDR instrument was not sensitive enough to accomplish the proposed science; this was not established until Phase B)
  • Mission homepage: http://www.bu.edu/spidr/overview.html
• HNX (Heavy Nuclei Explorer)
  • PI: Robert Binns (Washington U)
• PRIME (Primordial Explorer)
  • PI: Wei Zheng (Johns Hopkins U)
• STEP (Satellite Test of the Equivalence Principle)
  • PI: Francis Everitt (Stanford U)

2003 SMEX AO was a traditional, two-step AO. Two astrophysics proposals were selected for Phase A studies, and one of them (NuSTAR) was downselected to proceed into Phase B.

• NuSTAR (Nuclear Spectroscopic Telescope Array)
  • PI: Fiona Harrison (Caltech)
    • Selected: November 4, 2003
    • Downselected: January 26, 2005
    • Launched: June 13, 2012
    • Currently operating

• • Mission homepage: http://www.nustar.caltech.edu/
  • Data archive: https://heasarc.gsfc.nasa.gov/docs/nustar/
  • Wikipedia: https://en.wikipedia.org/wiki/NuSTAR
• DUO (Dark Universe Observatory)
  • PI: Richard Griffiths (Carnegie Mellon U)
  • Description: https://www.hq.nasa.gov/office/oss/codesr/smex/abstracts/duo.html

2007 SMEX AO was a traditional, two-step AO. Three astrophysics proposals were selected for Phase A studies, and one of them (GEMS) was downselected to proceed into Phase B.

• GEMS
  • PI: Jean Swank (NASA Goddard Space Flight Center)
    • Selected: May 29, 2008
    • Downselected: June 19, 2009
    • Terminated: June 2012 (GEMS was non-confirmed because of cost growth beyond the PI cost cap)
  • NASA Lessons Learned: https://km.nasa.gov/learning-lessons-from-gems/
  • Wikipedia: https://en.wikipedia.org/wiki/Gravity_and_Extreme_Magnetism
• JANUS (Joint Astrophysics Nascent Universe Satellite)
  • PI: Peter Roming (Pennsylvania State U)
• TESS (Transiting Exoplanet Survey Satellite)
  • PI: George Ricker (Massachusetts Institute of Technology)
  • Selected in 2013 as a MIDEX
    • MIDEX mission homepage: https://tess.gsfc.nasa.gov/
    • MIDEX mission Wikipedia: https://en.wikipedia.org/wiki/Transiting_Exoplanet_Survey_Satellite

2014 SMEX AO was a traditional, two-step AO. Three astrophysics proposals were selected for Phase A studies, and one of them (IXPE) was downselected to proceed into Phase B.

• IXPE (Imaging X-ray Polarimetry Explorer)
  • PI: Martin Weisskopf (NASA Marshall Space Flight Center)
    • Selected: July 30, 2015
    • Downselected: January 3, 2017
    • Launch targeted for late 2020
  • Mission homepage: https://wwwastro.msfc.nasa.gov/ixpe/
• PRAXyS (Polarimeter for Relativistic Astrophysical X-ray Sources)
  • PI: Keith Jahoda (NASA Goddard Space Flight Center)
  • Mission homepage: https://asd.gsfc.nasa.gov/praxys/
• SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer)
  • PI: James Bock (Caltech)
  • Mission homepage: http://spherex.caltech.edu/

2. Links to any open information on missions that were proposed but not selected. (Some PIs present their proposed missions at conferences, or post a paper on arxiv.)

3. Publication records for launched missions. The only successfully launched astrophysics SMEX missions are SWAS, GALEX, and NuSTAR.

From Fiona Harrison (NuSTAR PI) (Feb 10. 2017): The website is a little out of date. If you include publications from the NuSTAR team and guest investigators we have 306 submitted publications to-date. 272 of these are accepted, the rest are submitted and on the archive. There may be some more GO papers submitted that did not get posted on the archive. Here is a sample of high profile publications

1. Extended hard-X-ray emission in the inner few parsecs of the Galaxy.
   Perez, Kerstin M., Hailey, Charles J., Bauer, Franz E., et al., 2015, Nature, 520, 646.
2. An ultraluminous X-ray source powered by an accreting neutron star.
   Bachetti, M., Harrison, F. A., Walton, D. J., et al., 2014, Nature, 514, 202.
3. Asymmetries in core-collapse supernovae from maps of radioactive ⁴⁴Ti in Cassiopeia A.
   Grefenstette, B. W., Harrison, F. A., Madsen, K. K., et al., 2014, Nature, 506, 339.
4. A rapidly spinning supermassive black hole at the centre of NGC 1365.
   Risaliti, G., Harrison, F. A., Madsen, K. K., et al., 2013, Nature, 494, 449.
5. Ti-44 gamma-ray emission lines from SN1987A reveal an asymmetric explosion.
   Boggs, S. E., Harrison, F. A., Miyasaka, H., et al., 2015, Science, 348, 670.
6. Black hole feedback in the luminous quasar PDS 456.
   Nardini, E., Reeves, J. N., Gofford, J., et al., 2015, Science, 347, 860.
7. A fast and long-lived outflow from the supermassive black hole in NGC 5548.
   Kaastra, J. S., et al. 2014, Science, 345, 64.
8. The First Focused Hard X-ray Images of the Sun with NuSTAR.
   Grefenstette, Brian W., Glesener, Lindsay, Krucker, Säm, et al., 2016, ApJ, 826, 20.
9. Ejection of the Massive Hydrogen-rich Envelope Time with the Collapse of the Stripped SN 2014C. Margutti, Raffaella, Kamble, A., Milisavljevic, D., et al., 2017, ApJ, 835, 140
10. The NuSTAR Extragalactic Surveys: The Number Counts of Active Galactic Nuclei and the Resolved Fraction of the Cosmic X-ray Background.
    Harrison, F. A., Baloković, M., Brightman, M., et al., 2016, ApJ, 831, 185.

4. A statistical (anonymous) analysis of proposed SMEX missions vs science grade vs TMC grade.

The three most recent Astrophysics SMEX AOs were:

• NNH14ZDA013O 2014 Astrophysics SMEX

  Released: 17 Sep 2015

  Proposal due date: 18 Dec 2014

  Cost cap: $125M (FY15$) excluding launch vehicle

  13 Astrophysics SMEX proposals received

  Step 1 selection announced: 30 Jul 2015

  Step 1 selections:	IXPE, Martin Weisskopf (MSFC)
  	PRAXyS, Keith Jahoda (GSFC) SPHEREx, James Bock (Caltech)

  Step 2 downselection announced: 3 Jan 2017

  Step 2 downselection: IXPE, Martin Weisskopf (MSFC)

• NNH07ZDA003O 2007 SMEX (Astrophysics and Heliophysics)

  Released: 28 Sep 2007

  Proposal due date: 15 Jan 2008

  Cost cap: $105M (FY08$) excluding launch vehicle

  17 Astrophysics SMEX proposals received

  Step 1 selection announced: 29 May 2008

  Step 1 selections:	GEMS, Jean Swank (GSFC)
  	JANUS, Peter Roming (Penn State U) TESS, George Ricker (MIT)

  Step 2 downselection announced: 19 June 2009

  Step 2 downselection: GEMS, Jean Swank (GSFC)

• AO_03_OSS_02 2003 SMEX (Astrophysics and Heliophysics)

  Released: 3 Feb 2003

  Proposal due date: 2 May 2003

  Cost cap: $120M (FY03$) including launch vehicle; Pegasus launch cost $26.6-30.3M (FY03$)

  depending on launch site

  16 Astrophysics SMEX proposals received

  Step 1 selection announced: 4 Nov 2003

  Step 1 selections:	DUO, Richard Griffiths (Carnegie Mellon U)
  	NuSTAR, Fiona Harrison (Caltech)

  Step 2 downselection announced: 26 Jan 2005

  Step 2 downselection: NuSTAR, Fiona Harrison (Caltech)

Summary of Three Astrophysics AOs

Sorted by AO

Sorted by type of proposal

Explanation of columns

• Cost Cap (FY15$) No LV – The cost cap in the AO has been adjusted to FY15$ using a standard inflation index (not an indexed adjusted for the aerospace industry). For the 2003 AO, the median LV cost was subtracted; this introduces a variance of about $1.5M in the correction of the 2003 AO cost cap, depending on launch site.
• Proposals received – The number of complaint, astrophysics, full mission SMEX proposals received.
• Selectable proposals – The number of proposals that received Category I, II, or III. Out of the 23 selectable proposals, 9 were Category I, 12 were Category II, and 2 were Category III.
• Category IV proposals – Self explanatory.
• Science driver for Category IV? – Number of proposals for which a science major weakness was a driver for the Category IV assignment. Science major weaknesses include weaknesses in the merit of the proposed science investigation as well as weaknesses in the proposed payload. Note that the Category IV drivers do not add to the number of Category IV proposals because some proposals had multiple drivers for their Category IV assignment.
• Cost driver for Category IV? – Number of proposals for which a cost major weakness was a driver for the Category IV assignment. A cost major weakness means that the propose cost cannot be validated.
• Other TMC driver for Category IV? – Number of proposals for which a TMC major weakness other than cost was a driver for the Category IV assignment. TMC major weaknesses include technical, schedule, and management major weaknesses.

INPUT FROM THE COMMUNITY

Kevin France
March 08, 2017

Dear Committee on Astronomy and Astrophysics,

Below are responses to your request for information regarding a SMEX AO in 2018 or 2019.

1. If you have proposed in previous SMEX rounds, or are considering proposing in an upcoming round, do you see sufficient opportunities now, given the SMEX scope as currently defined?

   --- I was the deputy PI and project scientist on a 2014 SMEX proposal. I do see sufficient opportunity to access new observing wavelengths and techniques from a SMEX platform to justify the release of an astrophysics SMEX AO in 2019.

2. Which is more constraining, the cost cap or the launch capability? Why?

   ---- Cost cap: this directly limits the TRL of the technology proposed and the complexity of the instrumentation, both ultimately limit the science that can be accomplished from this platform. Even a relatively simple experiment quickly reaches the $95M (assuming reserve) that is allocated to the teams.

3. Are there any specific, small modifications to the scope definition that would enable you and your team to propose a feasible mission?

   ---- adhere more strictly to the explicit TRL requirements laid out in the AO. The previous rules, I believe, require TRL 6 by the end of phase A, but many major weaknesses were identified for TRL 4 and 5 technologies at the time of proposal submission, despite the included plan for advancing to TRL 6 by the end of Phase A.

4. Is there anything else you think should be considered in answering this question?

   --- this may not be a helpful statement, but trying to match reviewers with both scientific and technical expertise relevant to a given mission proposal would be very valuable addition to the process in terms of getting quality reviews, and ultimately, selecting the best combination of exciting and feasible science return from the SMEX platform.

   --- If there is an implicit requirement for having a NASA center play a major role in your SMEX proposal, please make this a formal requirement and announce it to potential proposers.

Best wishes,
Kevin France – University of Colorado, Boulder

James C. Green
March 08, 2017

Which is more constraining, the cost cap or the launch capability? Why? Neither of these is the limiting
factor in SMEX proposals.

The limiting factors are:

James Green Professor
University of Colorado, Boulder

Jack Burns
March 19, 2017

Dear Committee on Astronomy and Astrophysics:

Please find below my response to the question regarding sufficient compelling science in a SMEX to justify an AO in 2018/19. My comments below are based upon my experience as a recent PI on a SMEX proposal. Thanks for this opportunity to provide input.

J. Burns

1. If you have proposed in previous SMEX rounds, or are considering proposing in an upcoming round, do you see sufficient opportunities now, given the SMEX scope as currently defined?

   -- The most recent Astrophysics SMEX AO, released in 2014, specified a cost cap of $175M (FY15$), including access to space, with NASA-provided launch services (Pegasus equivalent) available at a cost of $50M. This cost cap ($175M) is sufficient to enable numerous scientifically compelling mission concepts.

2. Which is more constraining, the cost cap or the launch capability? Why?

   -- Overall, the Pegasus-class launch capability (volume, performance), and the associated cost for that launch capability, is substantially more constraining than the cost cap itself.

   -- The Pegasus-class launch performance substantially limits the range of accessible orbits, primarily to Low or Eccentric Earth Orbits, and the effective cost for that limited performance is very high (e.g., ~$150k/kg for a 600 km, 28.5 degree inclination LEO orbit).

   -- Alternative launch options, including launching as a secondary as well as higher performance vehicles with marginally higher cost, would enable a much broader range of mission concepts.

3. Are there any specific, small modifications to the scope definition that would enable you and your team to propose a feasible mission?

   -- Open the launch vehicle options to include other, more current, launch vehicles, as well as launching as secondary payloads. These could either be NASA-provided launches, or allow PI-managed launches as was allowed in the 2014 SMEX AO (e.g., “alternative access to space”).

   -- Providing a range of launch vehicle performance options and costs would allow PI Teams to perform additional trades to optimize their mission. For example, a slightly more expensive launch vehicle that could allow access to a Sun-Earth L2 orbit might result in relaxation of

4. technical requirements on the flight system and improved science return.

   -- It will be important to ensure the TMC reviewers are appropriately instructed with regard to how to evaluate proposals exercising any of these “non-typical” launch options to avoid this factor being used to assess a disproportionately higher risk for the proposal.

   -- Consider revising the relative weighting of the evaluation criteria, reducing the TMC weighting for the Step 1 evaluation. The most recent weighting (for both 2014 SMEX and 2016 MIDEX) was 40% science merit, 30% science implementation and 30% TMC, including cost risk. A revised weighting of 50% science merit, 35% science implementation and 15% TMC, including cost risk, would be consistent with a slightly higher risk posture for SMEX relative to MIDEX.

   -- This could be accomplished either by performing the same TMC review and applying the modified weightings in the categorization process, or by instructing the TMC reviewers to “lower the bar” somewhat for the SMEX proposal evaluations in determining which weaknesses are Major vs Minor.

5. Is there anything else you think should be considered in answering this question?

   -- Reducing the burden on the proposers for the Step 1 SMEX proposals would be very helpful. The current level of detail required for a SMEX ($175M cost cap) Step 1 proposal is nearly identical to that required for a MIDEX ($250M) and very comparable to that required for a Discovery ($450M) proposal. While commonality across the AO line is very helpful, the level of detail required should be proportionate to the value and risk posture of the mission [SMEX is Category 3/Class D, MIDEX is Category 2/Class C and Discovery is Category 2/Class B or C].

Pete Roming, SWRI
March 24, 2017

1. If you have proposed in previous SMEX rounds, or are considering proposing in an upcoming round, do you see sufficient opportunities now, given the SMEX scope as currently defined?

   I see the opportunities for doing SMEX-class science rapidly shrinking, particularly for missions that require optics. Because of the need to collect a small number of photons, many science cases require a single larger aperture. These larger aperture telescopes are more costly than what fits within the current SMEX budget, but their science cases are not justified under a MIDEX-class mission.

2. Which is more constraining, the cost cap or the launch capability? Why?

   Although both are constraining, the cost cap is more constraining. A modest change to the cost cap would allow sufficiently large instruments to obtain world-class science. A slightly larger launch vehicle would also allow this.

3. Are there any specific, small modifications to the scope definition that would enable you and your team to propose a feasible mission?

   An additional ~$25M (not including launch vehicle) would help with many of the tight constraints placed on a SMEX-class mission. A launch vehicle that had a 10-30% larger diameter than the Pegasus and 10% more throw-weight would also help considerably.

4. Is there anything else you think should be considered in answering this question?

Stephen Unwin, NASA JPL
March 24, 2017

Astronomers at the Jet Propulsion Laboratory, the California Institute of Technology, and colleagues:

Thanks for the opportunity to provide feedback on the important question of the efficiency of the SMEX Program. This topic is of considerable interest in the Caltech and JPL astrophysics communities, and many scientists and mission developers joined in discussing the questions that you posed. The following recommendations represent a broad consensus (though not complete unanimity) within the Caltech-JPL community and colleagues that participated in the discussions. We discussed SMEX in the overall context of NASA’s Explorer Program and limited our discussion by assuming that any proposed changes would be roughly cost-neutral.

Recommendations

1. We feel that the current SMEX opportunity structure is not optimal, and better science would result from eliminating two SMEX opportunities and replacing them with an additional MIDEX. This enables the most compelling science per dollar due to the capabilities enabled by the larger cost cap, the larger launch vehicle and orbit options. An additional opportunity per decade (i.e., roughly every ~3 years), would allow more frequent missions which enable the infusion of new science discoveries. We recommend this only if the 2018-19 SMEX is replaced by an additional MIDEX opportunity in a similar timeframe.
2. The Explorer Program should enhance the opportunities for rideshare and alternate launch vehicle access, to provide cost savings, enhanced science, and/or more flexible access to space.
3. We recommend a new line of much-cheaper ‘Mini-Explorers’ be instituted (see below). This would allow cheaper, more innovative, missions for focused science and for demonstrating new technologies, to be launched at a higher cadence.

Questions from the CAA

Is there still sufficient compelling science in a Small Explorer-sized (SMEX) mission to justify a SMEX Announcement of Opportunity (AO) in 2018 or 2019?

If the SMEX Program remains as currently structured, we feel there are not a sufficient number of both compelling and cost-credible concepts to justify a SMEX call in 2018-19, instead of a more enabling MIDEX opportunity. There are compelling astronomy experiments that can be done at or below $125M, but the specific nature of the SMEX Program as currently defined (technical, cost and risk requirements, etc.) strongly constrains science opportunities. Ideas that are unique, possibly innovative, or niche, are often viewed as too risky or not broad enough to justify the entire $125M cost cap (plus $50M for a Pegasus-class LV). Increasing the cost cap would obviously enable enhanced science, but we feel that a different mix of mission sizes would work better. MIDEX missions enable larger optics (astrophysics is still often driven by photon collection), precision attitude control, and orbits like L2 for thermal stability

and accessible field of regard, thereby opening up greater science return for the community. The larger MIDEX cost cap also means less reliance on foreign contributions. Note that nothing prevents a proposing team from developing a mission concept far below the MIDEX cost cap (but above the limiting SMEX constraints) and proposing a high science-value mission to NASA.

In addition, there are many ideas that could be done at significantly lower cost (around <$50M), if the opportunity were created to emphasize and incentivize innovation, new spacecraft providers, and rideshare/launch vehicle opportunities. We discuss this further below.

Which is more constraining, the cost cap or the launch capability?

Most of our scientists felt that the SMEX cost cap is more constraining than the launch vehicle. The launch is a major fraction of the total mission cost, as reflected in the $50M allowance for a Pegasus-class vehicle, and the fraction of the total cost cap that can be devoted to the instrument is relatively small.

We also recognize that the available volume, payload mass to orbit, and orbit altitude, are significant technical limitations. Choosing a smaller LV, or a rideshare, would provide significant savings to NASA, which the PI could then take as a cost “credit” to be used to propose well below the cap, or to enhance the science return.

This is a proven approach in planetary science to allow flexible launch scenarios, and was formally allowed in the last SMEX call. It could also apply to future MIDEX calls.

Are there any specific, small modifications to the scope definition that would enable you to propose a feasible mission?

We recommend that a new line of small ‘Mini-Explorers’ in the cost range of ~$25-$50M be instituted, in addition to rolling the SMEX line into MIDEX. These new missions would be larger than is possible within APRA Program, but managed more like APRA. Mini-Explorers would be well-suited to university-led teams (perhaps less so for large organizations like NASA centers). We are convinced that there are many small experiments (for focused science questions) in this cost range that could yield important science that are not possible with the current SMEX risk posture. With a much lower cost, a ‘Mini-Explorer’ experiment could be selected under AO guidelines that are significantly less onerous than for the present SMEX and MIDEX lines. This would allow more capable instruments and better science, in exchange for a modest increase in risk. Opportunities for ‘Mini-Explorers’ could be issued every couple of years.

Is there anything else you think should be considered in answering this question?

NASA should make ridesharing and alternate launch vehicles more attractive to proposers. There is a potential cost savings to NASA of allowing the PI to select a launch vehicle or rideshare that is well-matched to the proposed mission. This allows science missions that are more capable, but which are inherently riskier (especially in schedule) than using a NASA-provided vehicle. We recognize that ridesharing and alternate launch vehicles are, in fact, already allowed in the SMEX program. However there exists a disincentive to use these options because the PI must manage the perceived additional risk within the cost cap, and risking major weaknesses during the review process. The PI should not be expected to carry all of this risk within the cost cap. NASA should absorb the risk (especially in schedule), and this should be reflected in the AO guidelines and review merit criteria.

A practical solution may be the use of a launch broker. A commercial broker is much better informed about new opportunities (for instance, commercial missions that can provide rideshares) than a PI can be

expected to know about. Whether or not a broker is used, NASA should find ways to effectively open up access to space for Explorer-class missions by taking advantage of the ever-increasing ways of getting payloads to space. This has already been done very successfully with CubeSats and other very small payloads.

We recommend that NASA continue with the current SALMON Missions of Opportunity line, which in particular provides an effective means to enter into mission partnerships. The MOO timeline should not be coupled to the Explorer mission schedule. The suggested Mini-Explorer program has some overlap in scope with the MOO, so they would need to be made complementary.

INPUT FROM THE SMEX PRINCIPAL INVESTIGATORS

Fiona A. Harrison, Caltech
March 25, 2017

-- If you have proposed in previous SMEX rounds, or are considering proposing in an upcoming round, do you see sufficient opportunities now, given the SMEX scope as currently defined?

-- Which is more constraining, the cost cap or the launch capability? Why?

-- Are there any specific, small modifications to the scope definition that would enable you and your team to propose a feasible mission?

-- Is there anything else you think should be considered in answering this question?

Alan Title
March 24, 2017

Lockheed Martin Advanced Technology Center, Solar and Astrophysics Laboratory 3251 Hanover Street, Palo Alto, CA USA 94303

Small Satellites Are Critical for Science and Society

ABSTRACT

Satellite missions in the 50 to 300 kg class, Small Sats, can now be launched at significantly lower cost. This introduces a disruptive change in how small missions are developed. It is realistic to expect that in the short term mission costs can drop by a factor of three and it is reasonable to expect a drop by a factor of six in the next five years. Even in a fixed budget era, this would allow a greatly increased flight rate of NASA missions. A higher flight rate will expand the value of major missions by filling in the gaps in their data coverage. It will revolutionize our understanding of the Earth and the Earth-Sun system by allowing affordable constellations of satellites that provide data on spatial, temporal, and spectral scales that has been recognized for decades as essential. The new launcher capabilities have already led to new commercial ventures that are now exploiting the opportunities provided by platforms in space. These new ventures have in turn spawned a new generation of vendors of space ready hardware. The large number of Cube Sats and Small Sats already in space has generated a catalog of off-the-shelf components, electronics, and software that have been demonstrated by flight to be at TRL-9. We now have the tools to change the flight rate of SMEX class missions by an order of magnitude over the next decade while remaining inside the current budget of NASA SMEX missions. The expanded opportunity space will encourage greater scientific risk that will lead to new scientific discoveries that can evolve into the innovations that create economic growth.

Keywords: Sun, Corona, satellite, SMEX, Space Weather, Earth Observing

1. RARITY OF FLIGHT OPPORTUNITIES AND ITS CONSEQUENCES

Observing rapid temporal changes on the global scale on the Sun and in Near Earth system is critical to understanding the system’s evolution. While many important processes can be examined, and have been by individual missions, understanding how the Earth responds to events on the Sun is just not possible without comprehensive sampling of the entire domain. Over the past nearly three decades there have been three SMEX missions directed toward the Sun and three that have sampled the region from the Sun to the Thermosphere of Earth. The completeness of coverage, which can only be done from space, is not possible at the historic flight rate. The past SMEX missions have been designed to fill in and exploit the gaps in the coverage of the much larger missions developed and operated by NASA, ESA, and JAXA/ISAS. In that function the missions have been extremely successful scientifically.

In Astrophysics the SMEX program has served as a path finder for large missions, has filled gaps in the spectral coverage of large missions, exploited the discovery space revealed by large missions, and has provided the rapid responses necessary to understand a variety of astrophysical burst phenomena. But as the major astrophysical missions have become more focused, more expensive, and rarer, the need for missions directed at previously unforeseen processes has become increasingly more important. As an example, there is a need for imaging and spectroscopy of the large number of Earth like planets that Kepler has discovered. Over the past nearly three decades there have been four Astrophysics SMEX’s. This flight rate is not sufficient to maintain a well balanced astrophysics community.

NASA’s large missions usually take several decades from initial concept to the time the first data

reaches a scientist’s desk. As an example, the National Research Council (NRC) of the National Academy of Science’s Decadal Survey Astronomy and Astrophysics in the New Millennium (2000)¹ had in its list of the top ten recommended missions the Solar Dynamics Observatory (SDO) and the Next Generation Space Telescope (now named the James Web Space Telescope - JWST). SDO was launched on February 11, 2010 and JWST is planned to launch in 2018. Before these instruments received their high ratings from the Decadal Survey Science Panels more than decade was spent in defining mission requirements and producing primary costs estimates in enough detail to convince the members of the NRC panels of their reality. There were many missions under evaluation by the panels that more took 18 months to conclude. The barrier to get into the top ten was very high.

When the last SMEX in development is launched in 2017, it will be just over 29 years since the restart of the SMEX program in 1988. The average time from selection to launch has been 5.6 years. This does not include to time between the NASA Announcement of Opportunity and the selection, about 9 months, nor does it include the preparation time for development of a mission concept that is sufficiently mature to have a reasonable chance of selection. A time that may take a few years. As a result 7.5 +/- 2 years passes between an instrument concept and the start of scientific analysis.

Over the past three decades the advances in technology have revolutionized how we live, work, and drive. The technologies that have given us the internet, smart phones, and much safer and smarter cars are not in our missions flying in space because they were constructed from the parts that existed more than a decade ago. Instruments now in space often depend on detectors and electronics that can only be found in technology museums or at garage sales.

Nevertheless, announcement by NASA of great discoveries are hardly rare, so why change the flight rate now? As scientists we are like frogs in gradually heated water. Initially it is comfortable. But for the new generation of scientists the water is hot. Today a scientist excited about demonstrating their new ideas on a mission in space is likely to be discouraged after realizing a decade long internship is necessary to develop a reputation suitable for an institution to make the investment necessary for a SMEX mission proposal. Then for the a very few who are selected of a mission it will be nearly another decade before the mission produces data. Today a new Ph.D must balance a future in academic space science between other interesting scientific fields or to use their talents in the commercial space arena. Today a young engineer can chose to be on the ground floor of new space flight missions now in development by venture capital funded start-up organizations or take the risk of joining young scientists that desire to change our understanding of the universe.

While NASA, ESA, and JAXA have been nearly the only players in space science, India, China, UAE are emerging as developers of space programs. They are not burdened with the constraints that the big space agencies have imposed on themselves. The US is now moving into an era where other nations will be the serious competitors or even leaders in the space sciences. Our best young scientists and engineers will go where the data and engineering challenges are. It can not be forgotten that scientific breakthroughs and forefront engineering leadership are essential to economic leadership.

2. NEW OPPORTUNITIES NOW

What is different now? Historically the cost of going into space has been roughly 1/3 launcher, 1/3 spacecraft, and 1/3 instrument. The launcher is the disruptive factor that will change to how space missions are executed in the future. For example, the $62 million SpaceX Falcon 9 has the capacity to deliver 22,800 kg ($2700 /kg) to low earth orbit (LEO) and 8,300 kg to geosynchronous transfer orbit (GTO). (SpaceX is not the only company in new the launcher world.) By simply dividing 300 kg into 22,800 suggests that 76 Small Sats could fly on a single launch at a cost of $816 thousand each. While

this is unrealistic, a launch of seven Small Sats would lower the launch cost below $10 million per vehicle. The high carrying capacity also means that many future missions will have the capability to carry one or more attached payloads. Emerging is a brokerage industry that serves the need of matching a mission’s requirements to space available on scheduled launches. As an increasing number of commercial operators take advantage of the values of space operations and have room for attached payloads the cost of small satellite launches will drop still further. In summary, the near future should see the cost of launching a small satellite drop from the current $50 million to well below $10 million.

Now if history were a reasonable predictor of the future, the 1/3 rule of mission development would predict $10 million spacecraft and $10 million dollar instrument systems. An optimist would predict that current cost of $170 million for a SMEX mission can drop to $30 million. Such a reduction in cost would allow the current NASA SMEX budget to support a flight rate increase by a factor of four and allow $12.5 million for scientific data analysis for each of these missions.

Is such an optimistic view possible to execute? There are now vendors producing spacecraft for 200 kg payloads that cost of the order of $20 million. As more spacecraft for Small Sats are built, the non-reoccurring costs can be shared over more vehicles and it is reasonable to expect $10 million dollar spacecraft in the near future. So the critical question is, can state-of-the-art scientific payloads be produced for a $10 million target price? The recently concluded NRC report on the Achieving Science Goals with CubeSats² documented that highly-reliable-professionally-developed missions can be designed, built, and operated in space for a few million dollars. If the methodology of these successful scientific projects is be transitioned to higher mass missions, then $30 million Small Sat missions are possible.

A rapidly growing array of Commercial-of-the-Shelf (COT) components using standard software modules that have flown on CubeSats and Small Sats has created a catalog of TRL 9 components and subsystems. Available COT’s components, electronics, and software modules both constrains and focuses an instrument design team. Because engineering and the time to receive components and subassemblies is the major cost driver of an instrument development, clever science teams will find ways to achieve interesting science goals within cost limits that at present might seem impossible. The current generation of CubeSats has demonstrated that with development plans are tailored to mission requirements the professional levels of design and test needed for reliable operation in space can be done at significantly lower cost than historically has occurred on NASA missions.

Implicit in the words above is that NASA and other government agencies are the only sources of funding for space science missions. However, there is in the US a long history of private support of science instruments and investigations. But in the past the cost for space missions has been so high and the time to see results so long that private citizen support of space missions has not grown at a rate that pushes new developments. This is changing, the private funding of Starshot, the mission to a planet outside our solar system, by Yuri Milner and a missions to the Moon and Mars by Elon Musk may encourage private groups and Universities engage in the opportunities provide by space explorations.

3. DISRUPTION CAN NOT BE STOPPED

When the dinosaur’s environment could no longer support their life style rather than die out they they evolved into birds. This occurred because dinosaurs carried in their genes the information to execute change and the pressure of their environment drove it. NASA and the current generation of Aerospace companies together with the academic and engineering communities have the genes to adapt. It is only a matter of time. The faster this realization spreads the sooner we all will be able to fly more advanced instrumentation more frequently. We will learn how to more responsibly live in the Sun - Earth system that we reside and in the Universe that we may share with other civilizations.

REFERENCES

1. Astronomy and Astrophysics Survey Committee, Space Studies Board, National Academy of Sciences, 278 pages, 2003.

2. Achieving Science with CubeSats, Committee on Space Studies, Board, National Academies of Science, 130 pGESA, 2016.

Martin C. Weisskopf (MSFC-ST12)
March 22, 2017

I am pleased to respond to your question. I am the PI of the most recently selected SMEX, the Imaging X-Ray Polarimetry Explorer (IXPE). Your questions:

1. Is there still sufficient compelling science in a Small Explorer-sized (SMEX) mission to justify a SMEX Announcement of Opportunity (AO) in 2018 or 2019”

   I would argue that the answer is yes and offer my own experiment as proof of the availability of performing new and exciting science in the framework of a SMEX mission. The key features of IXPE that were that, for the first time, imaging X-ray Polarimetry would be utilized in our study of the complex and interesting X-ray emitting systems.

2. If you have proposed in previous SMEX rounds, or are considering proposing in an upcoming round, do you see sufficient opportunities now, given the SMEX scope as currently defined?

   Yes, I see sufficient opportunities now given the SMEX scope as currently defined. I have never felt constrained by the scope. It is an experimentalist’s challenge to fit within that scope but it is healthy not only for the particular mission, but also for the program in the attempt to limit overruns.

3. Which is more constraining, the cost cap or the launch capability? Why?

   This is a really tough question to answer. My choice is the launch capability. Crude cost modelling (say fully mass-based) would probably disagree, but I could build a better IXPE with say more diameter in the fairing without much cost increase and still stayed below the cost cap at the price of some cost margin albeit still above the margin required.

4. Are there any specific, small modifications to the scope definition that would enable you and your team to propose a feasible mission.

5. Probably unacceptable but further easing of the documentation requirements would go a long way to optimizing the science per unit dollar.

6. Is there anything else you think should be considered in answering this question?

   I haven’t the time to think this through carefully so I don’t have anything to add. A cop out I know. Sorry. Martin