1. Center for Lunar Origin and Evolution (CLOE)
4/22/2017
Center for Lunar Origin and Evolution (CLOE)
“Understanding the Formation and Bombardment History of the Moon”
PI: William Bottke, Southwest Research Institute

2. Southwest Research Institute in Boulder

3. Meet the CLOE Team! Luke Dones Steve Mojzsis Hal Levison Robin Canup
Amy Barr
Clark Chapman
William Bottke
Stephanie Shipp
Bill Ward
David Nesvorny
Erik Hauri
Jay Melosh

4. CLOE Themes and Organization
PI: William Bottke
Deputy PI: Clark Chapman
Theme I Lead: Robin Canup
Theme II Lead: Clark Chapman
Theme III: Lead: Hal Levison
E/PO Lead: Stephanie Shipp

5. CLOE Organizational Chart
4/22/2017
PI: William Bottke (SwRI)
Deputy PI: Clark Chapman (SwRI)
CLOE’s Executive Council (EC): Bottke, Canup, Levison, Chapman
Theme I. Lead: Robin Canup (SwRI)
Co-Is: Amy Barr, Bill Ward, Jay Melosh (U. Arizona), Erik Hauri (DTM)
Collaborators: Roger Phillips (SwRI).
Theme II: Lead: Clark Chapman (SwRI)
Co-Is: Steve Mojzsis (U. Colorado)
Collaborators: Herb Frey (GSFC), Barb Cohen (MSFC), Tim Swindle (U. Arizona), Dave Kring (LPI), Scott Anderson (SwRI)
Theme III: Lead: Hal Levison (SwRI)
Co-Is: Luke Dones (SwRI), David Nesvorny (SwRI)
Collaborators: Alessandro Morbidelli (Obs. Nice), David Vokrouhlicky (Charles U., Czech Republic), Dave O’Brien (PSI).
E/PO: Leader: Stephanie Shipp (LPI)
Co-I: Amy Barr (SwRI)

6. Why Should We Study the Moon?
“This is really cool”
“Been there, done that!”
We have a “Big Picture” problem:
The public has almost no idea why we should go back to the Moon from a science perspective.
Most planetary scientists have the same problem!

7. What Most People Do Not Consider
The Moon itself is fascinating, but it is also a “Rosetta Stone” for telling us about:
The unknown nature of the primordial Earth!
The critical last stages of planet formation throughout the solar system!

8. 2007 study by National Research Council.
Science Concepts
Three fundamental scientific concepts have emerged from our exploration of the Moon to date:
Lunar origin by giant impact
The existence of an early lunar magma ocean, and
The potential of an impact cataclysm at 3.9 billion years ago.
2007 study by National Research Council.

9. 2007 study by National Research Council.
Science Concepts
Three fundamental scientific concepts have emerged from our exploration of the Moon to date:
Lunar origin by giant impact
The existence of an early lunar magma ocean, and
The potential of an impact cataclysm at 3.9 billion years ago.
2007 study by National Research Council.

10. Theme 1: Formation of the Moon
Giant impact of Earth and Mars-sized protoplanet forms a disk of rocky/vapor material.
However, we still do not know whether such a disk can evolve into the Moon that we see today!
Impactor Trajectory
Early Earth
Iron core vs. stony mantle
Animation from Robin Canup

11. Theme 1: Formation of the Moon
Objective: Determine the implications of Giant Impact hypothesis for the Moon’s physical and compositional state
Approach: Self-consistent model of lunar origin, starting from an impact and ending with a fully-formed Moon
Lead: Robin Canup (SwRI)
Co-Is: Amy Barr (SwRI), Erik Hauri (Carnegie), Jay Melosh (Arizona), and William Ward (SwRI)

12. Simulating Moon-Forming Impacts
Goal: Determine initial dynamical, thermodynamical, and compositional properties of impact-generated protolunar disk
SPH/particle code: first 24-hours
CTH/grid code: first week

13. Protolunar Disk Evolution
Goals: Determine extent of Earth-Moon chemical mixing, volatile loss, rate & nature of Moon’s accumulation
Two-part coupled model: Evolution of vapor-melt disk inside Roche limit + simulations of Moon’s accretion outside Roche limit

14. Goals: Determine extent of melting in the early Moon
Initial Lunar State
Goals: Determine extent of melting in the early Moon
Simulate the Moon’s thermal state as it forms, including impact heating and radiative cooling.
Estimate magma ocean depth and degree of metal & silicate equilibration

15. 2007 study by National Research Council.
Science Concepts
Three fundamental scientific concepts have emerged from our exploration of the Moon to date:
Lunar origin by giant impact
The existence of an early lunar magma ocean, and
The potential of an impact cataclysm at 3.9 billion years ago.
2007 study by National Research Council.

16. 2007 study by National Research Council.
Science Concepts
Three fundamental scientific concepts have emerged from our exploration of the Moon to date:
Lunar origin by giant impact
The existence of an early lunar magma ocean, and
The potential of an impact cataclysm at 3.9 billion years ago.
2007 study by National Research Council.

17. 2007 study by National Research Council.
Science Motivation
Three fundamental scientific concepts have emerged from our exploration of the Moon to date:
Lunar origin by giant impact
The existence of an early lunar magma ocean, and
The potential of an impact cataclysm at 3.9 billion years ago.
2007 study by National Research Council.

18. What is Interesting About the Bombardment History of the Moon?
In this talk I will show you that
Southwest Research Institute is at the forefront of understanding the solar wind that fills the space around our solar system and its interaction at the galactic frontier!
Orientale Basin; Kaguya Mission

19. Ages of Lunar Samples
Most ancient lunar rocks cluster near ~ Ga.
Ar-Ar-based ages of basins cluster near 3.9 Ga.
All available Ar-Ar ages of highlands rocks as of Gaussians along bottom (of equal area) represent individual samples. Dark line (“ideogram”) is sum of those Gaussians. Data from Turner et al. (1973)

20. The Lunar Impact Rate Lunar impact rate has been variable with time.
Hartmann et al. (1981); Horz et al. (1991)

21. The Lunar Impact Rate Lunar impact rate has been variable with time.
Crater production rates >100 times higher >3.8 billion years ago.
Hartmann et al. (1981); Horz et al. (1991)

22. The Lunar Impact Rate Lunar impact rate has been variable with time.
Crater production rates >100 times higher >3.8 Gy ago.
Relatively constant crater rate since ~3.2 Ga.
Hartmann et al. (1981); Horz et al. (1991)

23. Lunar Late Heavy Bombardment
Were most large basins produced by a spike of impactors near ~ 3.9 Ga, creating a terminal cataclysm?

24. Lunar Late Heavy Bombardment
Or were most produced by a declining bombardment of leftover planetesimals from terrestrial planet formation?

25. Theme 3. Determining Lunar Impact Rates
In this talk I will show you that
Southwest Research Institute is at the forefront of understanding the solar wind that fills the space around our solar system and its interaction at the galactic frontier!
Lead: Hal Levison(SwRI)
Co-Is: David Nesvorny (SwRI), Luke Dones (SwRI)

26. Post Accretion and the LHB: Part 1
Sea of bodies:
Moon to Mars-sized bodies
Smaller planetesimals.
Some bodies pushed to high eccentricities & inclinations.
Here they live long enough to strike the Moon between Ga.
Location of
Asteroid Belt
Protoplanets
Planetesimals

27. Post-Accretion and the LHB: Part 2
Comets
Old view. Gas giants/comets formed near present locations (5-30 AU) and reached current orbits ~4.5 Gy ago.

28. Post-Accretion and the LHB: Part 2
Comets
Old view. Gas giants/comets formed near present locations (5-30 AU) and reached current orbits ~4.5 Gy ago.
Primordial disk of comets
New view. Gas giants formed in more compact formation between 5 to ~20 AU. Massive comet population existed out to ~30 AU.
Fernandez and Ip (1986); Malholtra (1995); Thommes et al. (1999; 2003)

29. Post-Accretion and the LHB: Part 2
Comets
Old view. Gas giants/comets formed near present locations (5-30 AU) and reached current orbits ~4.5 Gy ago.
Primordial disk of comets
New view. Gas giants formed in more compact formation between 5 to ~20 AU. Massive comet population existed out to ~30 AU.
Best developed and most successful scenario of this is the Nice Model.
Fernandez and Ip (1986); Malholtra (1995); Thommes et al. (1999; 2003)
Tsiganis et al. (2005)

30. Destabilizing the Outer Solar System
Tsiganis et al. (2005); Morbidelli et al. (2005); Gomes et al. (2005)
Watch what happens after 850 My!

31. The Nice Model
Tsiganis et al. (2005); Morbidelli et al. (2005); Gomes et al. (2005)
Jupiter/Saturn enter 1:2 mean motion resonance
Gravitational interactions with massive disk of comets causes migration. In this simulation, at 850 My, Jupiter/Saturn enter 1:2 MMR.
This pushes Uranus and Neptune into comet disk.

32. Imbrium Basin Formation on Moon
Lunar Basin Formation
Imbrium Basin Formation on Moon
Lunar basins may come from impacting comets/asteroids scattered by reorganization of solar system!

33. The Early Lunar Impact Rate
For illustration purposes only!
Goal. Calculate the nature of the impact flux between Ga.
Approach. New simulations that track how planetesimals evolved in the inner solar system prior to the Nice model event. Link work back to Theme 2.

34. Lead: Clark Chapman (SwRI) Co-I: Steve Mojzsis (U. Colorado)
Theme 2. Observational Constraints on the Bombardment History of the Moon
Objective. Find new “ground truth” to determine the lunar impact rate over its early (and late) history.
Lead: Clark Chapman (SwRI)
Co-I: Steve Mojzsis (U. Colorado)

35. Task 2.1 Bombardment Thermochronometry of Early Moon Earth, and Asteroids (Mojzsis)
Trail et al. (2005)
Goal. Study datable massive heating events in ancient zircons and other minerals from the Earth, Moon, and asteroids to determine ancient impact rates on these objects.
Approach. Many ancient zircons (ZiSiO4) have overgrowths that record thermal pulses. Using secondary ion mass spectrometry (SIMS), we will date these events and provide new constraints on the timing, intensity, and duration of lunar bombardment.

36. Example: Hadean Zircons from Jack Hills, Australia
Core ages are generally 4.2 Ga, while overgrowths are at ~3.95 Ga. Nothing is found in between.
Support for terminal cataclysm?

37. Task 2.2 Relative Lunar Cratering Chronology (Chapman)
Baldwin counted small craters (0.5 < D < 4 km) on/near lunar nearside craters to get their ages.
His method reproduces (within My) the ages of two craters with known ages:
Copernicus (~800 My)
Tycho (~110 My)
Baldwin (1985)

38. Lunar Impact Rates From Baldwin
Goal. Establish chronology of observable lunar geology using new crater counts.
Approach. Use Baldwin’s technique and latest lunar imagery to establish relative crater stratigraphy from present to LHB.
Absolute ages will come from Theme 3.
Baldwin (1985)

39. Other Institute Objectives
Training
We will be hiring 4 postdocs and 3 graduate students.
Graduate seminar on the formation and evolution of the Moon
Based at the University of Colorado; joint Planetary/Geology departments
Origin of the Earth-Moon System II: Conference and Book
Conference designed to present new work on the Origin of the Moon
The conference will lead to a book published through Cambridge Univ. Press.
Many opportunities for joint efforts with the NLSI teams.
Solar System Bombardment Focus Group

40. Lead: Stephanie Shipp (LPI). Co-I: Amy Barr (SwRI)
CLOE E/PO
Partnership with Summer Science Program, Inc. to inspire and educate future scientists
72 high school students/ year
6 week science experience observing and analyzing orbital elements of asteroids
2-day CLOE science project integrated into experience
Students encouraged to present at LPSC/NLSI conference
Materials available for other institutions to replicate.
Three foci to CLOE E/PO
Focus 1
Overall
Summer Science Program, Inc. begun in 1959, is one of the oldest and most successful summer enrichment programs for academically gifted high-school students. Most graduates enroll at highly selective universities; 60% pursue STEM careers and, of these, 20% select space science-related fields.
Each year students, mostly rising seniors from around the U.S. and world, are selected through a competitive application process. 72 are selected and participate in the 6-week experience at New Mexico Tech in Socorro, New Mexico, and Besant Hill School in Ojai, California. Students undertake authentic space science research encompassing telescopic observations of an asteroid and calculation of its orbital elements.
Evaluation will focus on content learning and perceptions and will be integrated into the existing SSPI evaluation protocol.
CLOE Component
Projects will be developed by the CLOE team, led by SSP alumna and Trustee Barr. CLOE team members will deliver six hours of background and methodology, and conclude by posing the scientific question. On the second day, CLOE team members interact with and advise student teams. Students present a brief summary of their scientific findings, successes, and challenges to their peers and the CLOE team.
Students will be encouraged to submit abstracts to LPSC and/or an NLSI conference. The materials developed will be added to SSPI’s curriculum database for use by other faculty.
Diversity / Financial Aid and Plans to Encourage Participation by Underserved and Underrepresented Audiences
SSP student body of 2004 to 2008 is 58% Caucasian, 30% Asian, 5% Hispanic, 2% Black, 1% American Indian, and 3% other. (Note: Current US Hispanic population is 15.1% --- rising to 24.4% by 2050, and current US Black population is 12.8%)
Program costs per student ($6800) are substantially greater than student fees ($3600); 60% receive financial aid.
In 2008, 12 students were accepted tuition-free. SSPI recently received a grant from the Ahmanson Foundation to provide free tuition to minority and disadvantaged students from the Los Angeles County Unified School District. Through partnerships with the NM State Legislature, SSP is tuition-free for NM residents.
To reach more Hispanic, Native American, and rural students, the CLOE E/PO team will work with SSPI to inform state science teachers and school councilor associations of this opportunity in the central western corridor (AZ, CO, ID, KS, MT, NE, NM, NV, ND, OK, SD, TX, UT, WY). The CLOE team will strongly encourage DSST students to apply and will mentor candidates and help them acquire scholarships.
Impact: 288 HS Students
Lead: Stephanie Shipp (LPI). Co-I: Amy Barr (SwRI)

41. CLOE E/PO Library programs to engage young explorers in lunar science
A suite of hands-on activities for library learning environments
90 children’s librarians prepared to bring lunar science into programs through 2-day workshops (CO and WY / ND and SD / ID, and MT)
Web-training of an existing nationwide network of 480 librarians
Continued support of network
Focus 2
Overall
Expand an existing LPI program, Explore!, that has provided training and space science materials to children’s librarians for over a decade.
activities for children ages 8 to 13
Module includes facilitator content and suggested books, websites, and other opportunities for further exploration. It is designed for informal learning environments, but aligned with national educational standards.
Workshops and Web casts are advertised and hosted in partnership with state library systems.
Evaluation uses existing evaluation instruments (developed in part for NSF evaluation of the trainings) to assess changes in participant content knowledge, as well as participant perceptions of lunar science and exploration, activities undertaken, workshop design, preparation and plans to implement with children, preparation and plans to train colleagues, etc.
CLOE Component
Module explores the Moon’s formation and Earth/Moon evolution: CLOE scientists ensure accuracy, work with E/PO team to design
CLOE scientists attend workshops and interact with librarians, and present CLOE/NLSI science in the Web casts
Free access sustained through the CLOE and Explore! websites
Diversity / Financial Aid and Plans to Encourage Participation by Underserved and Underrepresented Audiences
Library partners will recruit children’s and youth librarians who primarily work with underserved American Indian, Hispanic, and rural populations in:
CO (high Hispanic population)
WY, ND, SD, MT (high Native American population)
ND, SD, MT, ID (high rural population)
Impact: 10,800 children annually in 4 years

42. Impact: Enhanced student and public engagement
CLOE E/PO
CLOE Web page designed by students to engage the general public in NLSI science
Denver School of Science and Technology high school students and faculty
High-school students learn about CLOE and NLSI science, scientists, and careers
Design and maintain a web page that engages the public
Traditional and new media
Focus 3
Overall
DSST teachers and students will build an understanding of CLOE’s science and resources
Students will design the website and integrate content in consultation with science and technology faculty.
By the close of Year 1, a live public website will present CLOE and NLSI. The site may include:
animations, images, data, video clips
interviews, pod casts, student blogs, links to social networking sites (e.g., Facebook)
related events and opportunities for public involvement – including library programs
public lectures by NSLI scientists as live webcasts and archived
Evaluation will include assessing changes in student content knowledge and perceptions of lunar science and exploration and the design of the project, as well as web-based evaluations to assess public learning, engagement, plans to learn more, interaction with web site, etc.
CLOE Component
CLOE scientists will interact with students and teachers through monthly school visits and
Through the four project years, CLOE scientists visit classrooms and correspond with students, share new scientific findings, and serve as role models.
Students will be invited to visit SwRI to interview scientists and tour the facilities, and will be encouraged to “report on” NLSI events in which they participate
Site will be hosted by CLOE
Diversity / Financial Aid and Plans to Encourage Participation by Underserved and Underrepresented Audiences
DSST is a public charter high school with 35% Caucasian, 29% Black, 25% Hispanic, 11% other; 40% low-income students
Students encouraged to participate in SSPI experiences
Underrepresented students will be exposed to NASA, NLSI, lunar science, careers, and scientists
Impact: Enhanced student and public engagement

43. Any Questions?

46. CLOE Team Members
4/22/2017
PI: William Bottke; Deputy PI: Clark Chapman
CLOE’s Executive Council (EC): Bottke, Canup, Levison, Chapman
Theme I. Leader: Robin Canup
Co-Is: Amy Barr, Bill Ward, Jay Melosh (U. Arizona), Erik Hauri (DTM)
Collaborators: Roger Phillips (SwRI).
Theme II: Leader: Clark Chapman
Co-Is: Steve Mojzsis (U. Colorado)
Collaborators: Herb Frey (GSFC), Barb Cohen (MSFC), Tim Swindle (U. Arizona), Dave Kring (LPI), Scott Anderson (SwRI)
Theme III: Leader: Hal Levison
Co-Is: Luke Dones, David Nesvorny
Collaborators: Alessandro Morbidelli (Obs. Nice), David Vokrouhlicky (Charles U., Czech Republic), Dave O’Brien (PSI).
E/PO: Leader: Stephanie Shipp (LPI)
Co-I: Amy Barr (SwRI)

47. Task 3.1 The Post-Late Heavy Bombardment Era
Background Main Belt
Observed Families
Parker et al. (2008)
Goal. Determine how specific asteroid breakup events have affected lunar impact flux. Use info to compute absolute lunar crater ages.
Approach. Model formation age and evolution of asteroid families. Determine nature of lunar impact spikes. Couple to Theme 2 work.

48. Example: Asteroids Drift into Resonances by the Yarkovsky Effect
Koronis family
Observed
Model
Bottke et al. (2001)

49. Education and Public Outreach (E/PO)
LPI’s “Explore!” library program
Afterschool programs in lunar science and exploration ste up through programs in partnership with state libraries across 6 western states.
Targeted toward unrepresented populations
Summer Science Program, Inc.
Develop next generation of lunar scientists in collaboration with established SSP program.
Work with gifted high school and provide challenging lunar science program.
Develop CLOE web portal with high school students Denver School for Science and Technology.
Lead: Stephanie Shipp (LPI). Co-I: Amy Barr (SwRI)