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LCROSS. Our next mission to the surface of the Moon. Developed and managed by NASA Ames Research Center in partnership with Northrop Grumman. Goal: to test whether or not water ice deposits exist on the Moon. Why look for water?. Humans exploring the Moon will need water: - PowerPoint PPT Presentation
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LCROSSLCROSS
• Our next mission to the surface of the Moon.
• Developed and managed by NASA Ames Research Center in partnership with Northrop Grumman.
• Goal: to test whether or not water ice deposits exist on the Moon.
• Our next mission to the surface of the Moon.
• Developed and managed by NASA Ames Research Center in partnership with Northrop Grumman.
• Goal: to test whether or not water ice deposits exist on the Moon.
Why look for water?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!
• Carrying water to the Moon will be expensive!
• Learning to “Live off the land”would make human lunar exploration easier.
• Humans exploring the Moon will need water:– Option 1: Carry it there.– Option 2: Use water that may be there already!
• Carrying water to the Moon will be expensive!
• Learning to “Live off the land”would make human lunar exploration easier.
Early Evidence for WaterEarly Evidence for Water
Clementine Lunar Prospector
Two previous missions, Clementine (1994) and Lunar Prospector (1999)
gave us preliminary evidence that there may be deposits of water ice at
the lunar poles.
Clementine bistatic radar - 1994Clementine bistatic radar - 1994
• Circular polarization ratio (CPR) consistent with ice crystals in the south polar regolith.
• Later ground-based studies confirmed high-CPR in some permanently-shadowed craters.
• However, Arecibo scans have also found high-CPR in some areas that are illuminated, probably due to surface roughness.
• Are we seeing ice or rough terrain in dark polar craters?
• Circular polarization ratio (CPR) consistent with ice crystals in the south polar regolith.
• Later ground-based studies confirmed high-CPR in some permanently-shadowed craters.
• However, Arecibo scans have also found high-CPR in some areas that are illuminated, probably due to surface roughness.
• Are we seeing ice or rough terrain in dark polar craters?
Lunar Prospector neutron spectrometer maps of the lunar poles. These low resolution data indicate elevated concentrations of
hydrogen at both poles; it does not tell us the form of the hydrogen. Map courtesy of D. Lawrence, Los Alamos National Laboratory.
Lunar Prospector neutron spectrometer maps of the lunar poles. These low resolution data indicate elevated concentrations of
hydrogen at both poles; it does not tell us the form of the hydrogen. Map courtesy of D. Lawrence, Los Alamos National Laboratory.
Hydrogen has been detected at the poles by Lunar Prospector in 1999. Is it water ice???Hydrogen has been detected at the poles by Lunar Prospector in 1999. Is it water ice???
Lunar Prospector Impact – July 31, 1999Lunar Prospector Impact – July 31, 1999
• South pole impact at end of mission
• Low angle (6.3°), low mass (161 kg), and low velocity (1.69 km/s) less than ideal for water ice detection.
• No water detected.
• Results not conclusive.
• South pole impact at end of mission
• Low angle (6.3°), low mass (161 kg), and low velocity (1.69 km/s) less than ideal for water ice detection.
• No water detected.
• Results not conclusive.
New Evidence for WaterNew Evidence for Water
Data from 3 other probes has now shown that small amounts of water
are widespread across the surface of the Moon. The amount of water
may change during the course of the lunar day.
Deep Impact CassiniChandrayaan-1
Where will we look? Where will we look?
JPL/Goldstone Radar Image
Cabeus
1010
How could there be water at the lunar poles?
How could there be water at the lunar poles?
The Sun never rises more than a few degrees
above the polar horizon so the crater floors are in permanent shadow.
The crater floors are very cold with temperatures of
-238° C (-397° F, 35 K), so water molecules move very slowly and are trapped for billions of years.
Clementine Mosaic - South Pole
Where could water ice come from?Where could water ice come from?
Over the history of the Moon, when comets or asteroids impact the Moon's surface, they briefly produce a very thin atmosphere that quickly escapes into space.
Any water vapor that enters permanently shadowed craters could condense and concentrate there.
Where could water ice come from?Where could water ice come from?
Water molecules at lower latitudes may form from interactions with hydrogen streaming out in the solar wind. These water molecules may get baked out of the lunar soil and can then get trapped in polar craters.
Our Current Lunar MissionsOur Current Lunar Missions
Lunar Reconnaissance OrbiterLRO
Lunar Crater Observationand Sensing Satellite
LCROSS
Lunar Reconnaissance OrbiterLunar Reconnaissance Orbiter
• LROC – image and map the lunar surface in unprecedented detail
• LOLA – provide precise global lunar topographic data through laser altimetry
• LAMP – remotely probe the Moon’s permanently shadowed regions
• CRaTER - characterize the global lunar radiation environment
• DIVINER – measure lunar surface temperatures
• LEND – measure neutron flux to study hydrogen concentrations in lunar soil
• LROC – image and map the lunar surface in unprecedented detail
• LOLA – provide precise global lunar topographic data through laser altimetry
• LAMP – remotely probe the Moon’s permanently shadowed regions
• CRaTER - characterize the global lunar radiation environment
• DIVINER – measure lunar surface temperatures
• LEND – measure neutron flux to study hydrogen concentrations in lunar soil
• On-board propulsion system used to capture at the Moon, insert into and maintain 50 km mean altitude circular polar reconnaissance orbit
• 1 year exploration mission followed by handover to NASA science mission directorate
• On-board propulsion system used to capture at the Moon, insert into and maintain 50 km mean altitude circular polar reconnaissance orbit
• 1 year exploration mission followed by handover to NASA science mission directorate
Minimum Energy Lunar Transfer
Lunar Orbit Insertion Sequence
Commissioning Phase, 30 x 216 km Altitude
Quasi-Frozen Orbit, Up to 60 Days
Polar Mapping Phase, 50 km Altitude Circular Orbit, At least 1 Year
LRO Mission Overview LRO Mission Overview
LCROSS Mission ConceptLCROSS Mission Concept
• Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that may reach over 10 km about the surface
• Observe the impact and ejecta with instruments that can detect water
• Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that may reach over 10 km about the surface
• Observe the impact and ejecta with instruments that can detect water
Excavating with 6.5-7 billion JoulesExcavating with
6.5-7 billion Joules
• About equal to 1.5 tons of TNT
• Minimum of 200 tons lunar rock and soil will be excavated
• Crater estimated to have ~20-25 m diameter and ~3-5 m depth
• Similar in size to East Crater at Apollo 11 landing site
• About equal to 1.5 tons of TNT
• Minimum of 200 tons lunar rock and soil will be excavated
• Crater estimated to have ~20-25 m diameter and ~3-5 m depth
• Similar in size to East Crater at Apollo 11 landing site
LCROSS Mission SystemLCROSS Mission System
• Shepherding Spacecraft: guides and aims the Centaur to its target and carries all of the critical instrumentation.
• CentaurUpper Stage: provides the thrust to get us from Earth orbit to the Moon and will then be used as an impactor.
• Shepherding Spacecraft: guides and aims the Centaur to its target and carries all of the critical instrumentation.
• CentaurUpper Stage: provides the thrust to get us from Earth orbit to the Moon and will then be used as an impactor.
14.5 m
•Visible (263–650 nm) emission and reflectance•spectrometry of vapor plume, ejecta cloud•Measure grain properties•Measure emission H2O vapor dissociation,OH- (308 nm) and H2O+(619nm) fluorescence
UV/Vis Spectrometer
•NIR (1.2–2.4um) emission and reflectance•Spectrometry of vapor plume, ejecta cloud•Measure grain properties•Measure H2O ice features•Occultation viewer to measure water vapor absorption by cloud particles
NIR Spectrometer
•NIR (0.9–1.7 um) context imagery•Monitor ejecta cloud morphology•Determine NIR grain properties•Water concentration maps
NIR Cameras
•MIR (6.0–13.5 um) thermal image•Monitor the ejecta cloud morphology•Determine MIR grain properties•Measure thermal evolution of ejecta cloud•Remnant crater imagery
Thermal Cameras
•Three color context imagery•Monitor ejecta cloud morphology•Determine visible grain properties
Color Camera
•Measures total impact flash luminance•(425–1,000 nm), magnitude, and decay of flash•Sensitive to total volatile soil content, regolith depth and target strength
Flash Radiometer
SpectrometerTelescopes
Save $ and Time by Using an Existing Structure Designed to Carry Heavy
Payloads During Launch
Save $ and Time by Using an Existing Structure Designed to Carry Heavy
Payloads During Launch
EELV Secondary Payload Adapter or ESPA Ring
But how do you make a spacecraft out of something that looks like a sewer pipe?
Put LRO on top
Attach bottom of
ESPA Ring to top of rocket
Use ESPA ring to make
LCROSS spacecraft
Answer: Put Equipment Around the Rim and Tank in the Middle
Answer: Put Equipment Around the Rim and Tank in the Middle
Propellant Tank
ESPA Ring
Solar Array
Equipment Panel (1 of 5)
Integrated LCROSS Spacecraft
Different Panels Perform Different Functions
Different Panels Perform Different Functions
Solar Array
Batteries
Science Instruments
Power Control
Electronics
Command and Data Handling
Electronics (including computer)
Attitude Control and Communications
Electronics
LCROSS Viewed From Above without Insulation
Panel Approach Makes LCROSS Easier to Put Together
Panel Approach Makes LCROSS Easier to Put Together
LCROSS with Panels Laid Flat for Integration of Electronics
Other Equipment Includes Two Types of Antennas to Talk Back to Earth
Other Equipment Includes Two Types of Antennas to Talk Back to Earth
Omni (Low Gain) Antenna (1 on each
side)
Medium Gain Antenna (1 on each side)
And Sensors to Determine Spacecraft Attitude (Pointing)
And Sensors to Determine Spacecraft Attitude (Pointing)
Star Tracker
Sun Sensors (10 total)
Solar Array
Propulsion System Must Maneuver and Point the Spacecraft
Propulsion System Must Maneuver and Point the Spacecraft
Propellant Tank
(40.85” dia)Post
Supports Thrusters
(1 of 4)
5 lb Thruster for
Maneuvers (1 of 2)
1 lb Thruster for Attitude Control
(1 of 8)
Launch: June 18, 2009Launch: June 18, 2009
• Both LCROSS and LRO shared space aboard an Atlas V launch vehicle.
• Launch occurred at Cape Canaveral.
• Both LCROSS and LRO shared space aboard an Atlas V launch vehicle.
• Launch occurred at Cape Canaveral.
• We used the Atlas V Launch Vehicle.• This is the latest version in the Atlas
family of boosters.• Earlier versions of Atlas boosters
were used for manned Mercury missions 1962-63.
• Atlas V has become a mainstay of U.S. satellite launches.
• NASA has used Atlas V to launch MRO to Mars in 2004 and New Horizons to Pluto and the Kuiper Belt in 2006.
• We used the Atlas V Launch Vehicle.• This is the latest version in the Atlas
family of boosters.• Earlier versions of Atlas boosters
were used for manned Mercury missions 1962-63.
• Atlas V has become a mainstay of U.S. satellite launches.
• NASA has used Atlas V to launch MRO to Mars in 2004 and New Horizons to Pluto and the Kuiper Belt in 2006.
Launch Vehicle
• Launch was from Space Launch Complex 41 (SLC-41) at Cape Canaveral.
• Historic site where many previous missions launched:
• Helios probes to the Sun• Viking probes to Mars• Voyager planetary flyby and
deep space probes• Mars Reconnaissance
Orbiter• New Horizons spacecraft to
Pluto and Kuiper Belt
• Launch was from Space Launch Complex 41 (SLC-41) at Cape Canaveral.
• Historic site where many previous missions launched:
• Helios probes to the Sun• Viking probes to Mars• Voyager planetary flyby and
deep space probes• Mars Reconnaissance
Orbiter• New Horizons spacecraft to
Pluto and Kuiper Belt
Launch Site
When?When?
• LRO/LCROSS launched June 18, 2009.
• This will lead to impact at 11:30UT on October 9 for LCROSS.
• Impact will target the South Pole region of the Moon.
• LRO/LCROSS launched June 18, 2009.
• This will lead to impact at 11:30UT on October 9 for LCROSS.
• Impact will target the South Pole region of the Moon.
Centaur-LCROSS-LRO at TLICentaur-LCROSS-LRO at TLI
LRO SeparationLRO Separation
LCROSS Lunar Flyby: L + 5 daysLCROSS Lunar Flyby: L + 5 days
Lunar Flyby: June 23, 2009Lunar Flyby: June 23, 2009
LCROSS Trajectory: The Long and Winding Road
LCROSS Trajectory: The Long and Winding Road
• Flyby transitioned to Lunar Gravity Assist Lunar Return Orbits (LGALRO).
• 3 LGALRO orbits about Earth (~36 day period).
• Long transit also provides time to vent any remaining fuel from Centaur.
• Flyby transitioned to Lunar Gravity Assist Lunar Return Orbits (LGALRO).
• 3 LGALRO orbits about Earth (~36 day period).
• Long transit also provides time to vent any remaining fuel from Centaur.
LCROSS Separation: Impact - 9 hrsLCROSS Separation: Impact - 9 hrs
Centaur ImpactCentaur Impact
Centaur ImpactCentaur Impact
Into the PlumeInto the Plume
• During the next 4 minutes, the Shepherding Spacecraft descends into the debris plume, measures its composition, and transmits this information back to Earth.
• The Shepherding Spacecraft then ends its mission with a second impact on the Moon.
• During the next 4 minutes, the Shepherding Spacecraft descends into the debris plume, measures its composition, and transmits this information back to Earth.
• The Shepherding Spacecraft then ends its mission with a second impact on the Moon.
Impact Observation Campaign
Public and Student Observation
Amateurs and students with 10 to 12-inch telescopes may be able to observe and image the impact plume, and participate in the mission science.
Public and Student Observation
What areas can see the impact?
Land masses facing the Moonat time of impact
Lit and dark areas of EarthFacing the Moon at time of impact
How to contribute.
LCROSS Observation Discussion Grouphttp://groups.google.com/group/lcross_observation
LCROSS Citizen Science Image Management Sitehttp://apps.nasa.gov/lcross/
Public and Student Observation
How do I prepare for a public impact event?
No telescope? No view? No Problem! The views from cameras on LCROSS and in Mission
Control will be broadcasted on NASA TV and streamed on www.nasa.gov starting at 6:20 AM EDT.
How do I prepare for an impact event at my venue?
Visit the LCROSS education page at http://lcross.arc.nasa.gov/education.htm
•Presentations•Graphics•Videos•Tutorials•Educator Guides•Links to Education Programs including My Moon and GAVRT•The LRO/LCROSS Planetarium Show•Mission Team Member Biographies•And Much More!
LCROSS taken through Liverpool 2-meter Telescope, La Palma, Canary Islands – Robert Smith
LCROSS in flight taken through an amateur 16-inch telescope – Paul Mortfield
LCROSS in flight taken through an amateur 16-inch telescope – Paul Mortfield
QuestionsQuestions