NASA's LCROSS (Lunar Crater Observation and Sensing Satellite) Mission: Science Results and Hands-On Classroom Activities from the LCROSS Science Team

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1 LIVE INTERACTIVE YOUR DESKTOP NASA's LCROSS (Lunar Crater Observation and Sensing Satellite) Mission: Science Results and Hands-On Classroom Activities from the LCROSS Science Team Presented by: Jennifer Heldmann and Brian Day January 31, 2011

2 Dr. Jennifer L. Heldmann NASA Ames Research Center Division of Space Sciences Moffett Field, CA 94035

3 LCROSS...at a glance... Launch: June 18, 2009 Impact: October 9, 2009

4 Why LCROSS? Mission Primary Objective: To test whether or not water ice deposits exist on the Moon.

5 Why Look for Water? Humans exploring the Moon will need water: Option 1: Carry it there* Option 2: Use water that may be there already Learning to Live off the land could make (longterm) human lunar exploration easier. (*At $10K/lb to orbit. $3-5K more to Moon. At 8 lbs/gallon, it could cost >$100,000/gallon of water to the Moon.)

6 Early Evidence of Water Clementine (1994) Lunar Prospector (1999) Two previous missions, Clementine and Lunar Prospector gave us preliminary evidence that there may be deposits of water ice at the lunar poles.

7 Enhanced Hydrogen at the Lunar Poles Need to understand Quantity, Form, and Distribution of the hydrogen. The lunar water resource can be estimated from a minimal number of ground-truths. Early and decisive information will focus and simplify future lunar missions.. Above data from the Lunar Prospector mission ( ).!

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9 Let s pause for questions from the audience

10 The LCROSS Experiment Impact the Moon at 2.5 km/sec (5,600 mph) with a ~2366 kg (5216 lb) Centaur upper stage and create an ejecta cloud into the sunlight for observation. Observe the impact and ejecta. Impact the Moon (again): Four minutes later the ~625 kg (1378 lb) LCROSS Shepherding Spacecraft itself impacts at 2.5 km/s m

11 Spacecraft & Impactor

12 Mission Day 5 Lunar Swingby This was the scene of Lunar Swingby, June 23, ~2:30 a.m., Science Operations Center (SOC) at NASA Ames Research Center.

13 Where did we go and why? Target Selection Criteria: 1. Ejecta Illumination 2. Association with hydrogen 3. Observable to Earth 4. Smooth, flat terrain LCROSS Visible Camera Image :00 UTC Cabeus Crater Final decision considered available data, status of LCROSS payload, ability of LRO to observe, and limits of Earth observing for each site.

14 Where did we go? Cabeus A: Best Earth observing (not perfect since backdrop would have been lit moon) Hydrogen association was questionable Cabeus B: No obvious association with hydrogen Cabeus: Obvious hydrogen, but worst Earth observing LCROSS Visible Camera Image :30 UTC (Viewpoint from LCROSS, Oct 9)

15 Where did we go? Expected Plume Area (Viewpoint from Earth, Oct 9) Nancy Chanover, APO

16 Let s pause for questions from the audience

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18 Impact Experiments Predicted What we think we did Schultz et al. (2010)

19 What did we see? Multi-pixel signature >1km structure t+0s t+2s t+4s MIR_S1_W0000_T m651.png MIR_S1_W0000_T m653.png MIR_S1_W0000_T m655.png t+6s t+8s t+10s MIR_S1_W0000_T m657.png MIR_S1_W0000_T m659.png MIR_S1_W0000_T m159.png (Thermal signature seen in mid-ir cameras t+2-10s believed to be impact-heated ballistic ejecta that did not get into sunlight (low-angle plume). Ejecta after 4s is within a single pixel, ~1km/pix at this altitude.)

20 What did we see? Impact + 1 sec + 3 sec + 5 sec + 7 sec 6 km + 9 sec + 11 sec + 13 sec + 15 sec Warm (>-60 C) ejecta cast out 3 km in diameter MIR camera = microns

21 What did we see? (Observed 0.4s rise+0.7s decay in near infrared, but delayed 0.3s after impact. Interpretation: hit fluffy, volatile-rich surface layer.)

22 Radiance - Preimpact Radiance Wavelength (microns)

23 μ

24 What did we see?

25 High Angle vs Low Angle plume

26 High Angle vs Low Angle plume From D. Goldstein, D. Summy, U Texas at Austin

27 What did we see? Cam1_W0000_T m473 Schultz, et al (2010) (Observed expanded ejecta cloud km in diameter at 20s after impact. Visible camera imaged curtain at t+8s through t+42s, before cloud dropped below sensitivity range).

28 Cam1_W0000_T m473 What did we see?

29 What did we see? LCROSS NIR Camera image from about 14 km above surface 100 m LCROSS Crater (We created a crater m in diameter)

30 What did we see? LCROSS Mid-IR Camera Image of Crater t=252s (We detected the thermal signature of the ejecta blanket in both MIR Cameras. These cameras were sensitive down to -50C/220K.)

31 Let s pause for questions from the audience

32 LCROSS Water Measurement

33 NIR Nadir spectrometer fitting Spectra fit using linear fitting routine The goodness of fit demonstrated with each added component by Χ 2 /ν parameter Water ice, H2O(s) and water vapor H2O(g) are added in steps two and three The large change in Χ 2 /ν (>ΔΧ 2 /ν=0.23 for 6 parameter fit across 95 values) indicate with a greater than 3σ confidence that water ice and vapor are needed to fit the spectra Fits to NIR Spectra

34 Water Vapor in Ejecta Cloud Nadir NIR spectrometer: 0-24 sec after impact

35 Water Ice in Ejecta Cloud Nadir NIR spectrometer: sec after impact

36 Observation of OH OH Emission

37 So... How Much Water? We sampled only one area, created a 20-30m diameter crater, at few meters depth. We excavated ~250,000 kg (250 metric tons) regolith Of that only kg material got into sunlight. Of that only kg were within the 1 FOV of the spectrometers Band depths of H 2 O 1.4 & 1.8um features indicate 145 kg H 2 O vapor+ice OH emission strength at nm indicate 110 kg H 2 O vapor+ice gallons of water mean water concentration 5.6 wt% ± 2.9 wt% (by mass) M gal H2O/1 ton soil ; LCROSS 10 gal H2O/1 ton soil

38 Summary of Selected UV/Vis Identifications (First 18 sec after impact) Schultz et al. 2010

39 Earth Based Observations More than 25 Observatories Successfully Observed Na Observations from Kitt Peak (Killen et al., 2010) OH Observations from HST (Storrs & Colaprete, 2010) Initial Results: Moon Imaging of plume was difficult due to diffuse cloud (as opposed to confined curtain) However, there are hints of water in some spectra Two observatories observed Sodium flash HST measured OH exosphere (preliminary finding) Observatories Canada-France-Hawaii (CFHT) Lick Observatory Apache Point Observatory IFA Haleakala IRTF Kitt Peak, solar telescope MMT Kitt Peak 2.1 m MRO (Magdalena Ridge) Palomar Keck Table Mt Gemini North Faulkes Telescope North Subaru VATT Korea Astronomy & Space LRO Science Institute Mt Wilson Odin Air Force AEOS Telescope Hubble Space Telescope Allen Telescope Array IKONOS, GeoEye-1 Large Binocular Telescope EO-1 Tortugas Mtn Observatory

40 The LCROSS Experiment: Smooth or Chunky? Evenly Distributed, low concentrations Smooth Na Observations from Kitt Peak (Killen et al., 2010) Higher, infrequent concentrations Chunky Processes such as impacts, diffusion, topography and sputtering may effect the distribution at a variety of scales

41 The LCROSS Experiment: Smooth or Chunky? Evenly Distributed, low concentrations Smooth Na Observations from Kitt Peak (Killen et al., 2010) Higher, infrequent concentrations Chunky LCROSS data suggests Chunky model Processes such as impacts, diffusion, topography and sputtering may effect the distribution at a variety of scales

42 In Summary Impact occurred in a volatile rich area: Water and other stuff!! (e.g., CH 4, CO 2, SO 2, NH 3, Na, K, CO, NH 2 ) possibly observed more work needed to get unique identification Data indicates significant amounts of water (>150 kg vapor and ice) The amount and types of volatiles suggest: The very cold temperatures sequester all sorts of volatiles Multiple source model viable Science and space exploration is fun and exciting!

43 Let s pause for questions from the audience

44 High-Impact Lunar Education Educational Activities from the LCROSS Mission Brian Day NASA Lunar Science Institute

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46 Quest Challenge: Cratering the Moon

47 Cratering the Moon NASA can simulate cratering impacts at the Ames Vertical Gun Range. Allows study of: Different impactor shapes, masses and compositions Different impact velocities and angles Different target compositions and structures

48 In the Cratering the Moon activity, students design their own lunar impact simulator. They conduct a study to determine what role the angle of incidence of an impact plays in determining how effective an impactor is in excavating material from beneath the Moon s surface.

49 Fresno Co. Juvenile Justice Campus Student designed lunar impact simulator ms totaling 60 students creating designs around LCROSS Impact the Moon C nstrates continues utilization of resources. sfully engaging a particularly challenging student audience

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51 Let s pause for questions from the audience

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54 Lunar Sample Educational Disk Program Six samples of lunar material (three soils and three rocks) encapsulated in a six inch diameter clear lucite disk are available for you to borrow and bring into your classroom. The disk is accompanied by written and graphic descriptions of each sample in the disk. Mr. Louis Parker JSC Exhibits Manager National Aeronautics and Space Administration Lyndon B. Johnson Space Center Mail Code AP 2101 NASA Parkway Houston, Texas Telephone: FAX: louis.a.parker@nasa.gov

55 With Moon Zoo, students and members of the public can assist lunar scientists in analyzing the high resolution images returned by the LROC instrument aboard the Lunar Reconnaissance Orbiter. They perform crater counts, search for boulders, and other interesting landforms.

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57 Participatory Exploration Student Telemetry Team Directly involving thousands of students around the world in the mission. Extension of GAVRT Goldstone Apple Valley Radio Telescope run by Lewis Center fo Educational Research. Students can remotely operate the 34m DSS 12 & DSS 13 Goldstone dishes from thei classrooms.

58 Participatory Exploration - Student Telemetry Team Monitored spacecraft omni during transit. Conducted Doppler studies en route. Monitored medium gain transmissions during terminal approach and determined time of LOS. Outstanding partnership opportunity for other missions post LCROSS.

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60 Selected Online Resources Lunar Samples Program - Exploring the Moon - Lunar and Planetary Institute - My Moon - Explore! - NASA Lunar Science Institute - LRO - LCROSS - Solar System Exploration at JPL - Year of the Solar System - Moon Zoo - LCROSS Cratering the Moon Challenge - LCROSS Exploration through Navigation Challenges Space NASA - Ice Zones - Goldstone Apple Valley Radio Telescope (GAVRT) -

61 Thank you to the sponsor of tonight's Web Seminar:

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64 National Science Teachers Association Dr. Francis Q. Eberle, Executive Director Zipporah Miller, Associate Executive Director Conferences and Programs Al Byers, Assistant Executive Director e-learning NSTA Web Seminars Paul Tingler, Director Jeff Layman, Technical Coordinator LIVE INTERACTIVE YOUR DESKTOP