1 / 19

Principle Investigator Payload Manager

Anthony Colaprete. Principle Investigator Payload Manager. LCROSS Background. Lunar Prospector detected an increase in hydrogen concentration over the lunar poles. The debate over the form, concentration and distribution has continued ever since.

deacon
Download Presentation

Principle Investigator Payload Manager

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Anthony Colaprete Principle Investigator Payload Manager

  2. LCROSS Background Lunar Prospector detected an increase in hydrogen concentration over the lunar poles. The debate over the form, concentration and distribution has continued ever since. If the hydrogen in an accessible and usable form, it could be a potential resource? The form, distribution and concentration of [H] relevant to inner solar system asteroid/comet fluxes, lunar volatiles and planetary evolution. SP Hydrogen Abundance Feldman et al., 1998 LCROSS will provide the most unambiguous data set to date as to the nature of lunar hydrogen 2

  3. Question Addressed by LCROSS 3 • Nature and form of the hydrogen? • Water, hydrated minerals, hydrocarbons? • Grain size? • Distribution within regolith? • Nature of PSR regolith? • Strength? Depth? • Grain size? • Composition? • Is it similar to Apollo sites? • The Lunar Atmosphere / Volatile Processes? • How does the Lunar atmosphere respond? • What are the times scales for recovery? • How do volatiles/dust migrate? 3

  4. Lunar Polar Hydrogen: What we do know Deconvolved Hydrogen Maps (Elphic et al., 2007) Original Lunar Prospector Hydrogen Map (Maurice et la., 2003) • Water is heterogeneous from one crater to another • Accumulation/retention processes differ at carter scales of ~50-100 km? • Possibly different at smaller scales. 4

  5. The LCROSS Experiment: Smooth or Chunky? Higher, infrequent concentrations “Chunky” Evenly Distributed, low concentrations “Smooth” Processes such as impacts, diffusion, topography and sputtering may effect the distribution. 5

  6. The LCROSS Mission Launch stacked with LRO May 21, 2009 2. 1. After Lunar swing-by, enter a 3.5 month cruise around Earth 3. S-S/C observes impact, ejecta cloud and resulting crater, making measurements until impacting itself August 28, 2009, target the Centaur Upper Stage and position S-S/C to fly four minutes behind 4. 6

  7. Predicted Centaur Crater Size NASA AVRG Experiments SPH Modeling Schultz et al., 2008) Korycansky et al., 2008) East Crater ~30 meters 7

  8. The Impact – How Does it Compare? Estimates of the total ejecta mass as a function of impact angle for four impactors: LCROSS, LCROSS S-S/C, Lunar Prospector (LP), and SMART-1 LCROSS LCROSS S-S/C SMART-1 (hill side impact) SMART-1 (grazing impact) 8 LP

  9. The LCROSS Spacecraft 9

  10. The LCROSS Payload Flash Radiometer NIR Cameras Visible Color Camera Solar NIR Spec MIR Cameras NIR Spectrometer UV/Visible Spectrometer 10

  11. Yours Truly…in Five Wavelengths NIR 2 NIR 1 Visible MIR 1 MIR 2

  12. LCROSS Wavelength Coverage VSP VSP NIR1 NIR2 NSP MIR1: 7-9 mm MIR2: 7-12 mm

  13. Ground Based Observations Observatories Planning Observations: HST Odin (EU) CFHT Apache Point IRTF MMT (Az) UKIRT MRO Keck Gemini North Subaru ASSI (Korea) Hawaii lunar elevation = 39.9 deg @ impact Impact @ 06:30 UTC 13

  14. Impact Expectations: Earth Brightness (per 1 sqr arc sec) Curtain Area Average Brightness 14

  15. Summary • We’ll know in about 5 months! • Earliest likely impact date August 28, 2009 (for an May 21 launch) • Should be visible from Earth in the Pacific (including west coast) • Impact target selection an on-going process, currently headed north • LCROSS SC and Instrument development demonstrated a novel approach: High scientific return per dollar spent 15

  16. Backup Slides

  17. Expectations: LCROSS Water Detection Calculated ejecta cloud radiance (left axis) and synthetic NIR spectrometer data for 1% water content 17

  18. Expectations: Curtain Brightness The radiance for the ejecta cloud only (derived be subtracting off the spectra from the lunar surface) for several times after Centaur impact. 18

  19. The LCROSS Experiment: Smooth or Chunky? • Aerial fraction for 10 m craters that is in equilibrium, i.e., “wet”, is: • ~1 – Crater Diameter2/Crater Spacing2 = 1.-102/1002 = 99% • Top meter sensed by LP is near the derived value: high concentration pockets (water greater than few %) in the top meter not likely….the Smooth model is predicted. 19

More Related