NASA's Lunar Atmosphere and Dust Environment Explorer: Little Mission, Big Science - Presented by: Dr. Rick Elphic and Brian Day
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LIVE INTERACTIVE LEARNING @ YOUR DESKTOP
NASA's Lunar Atmosphere and
Dust Environment Explorer:
Little Mission, Big Science
Presented by: Dr. Rick Elphic and Brian Day
May 31, 2011
Lunar Atmosphere and Dust Environment
Explorer: Little Mission, Big Science
May 31, 2011
NSTA Webinar
Rick Elphic,
LADEE Project Scientist
NASA Ames Research Center
Moffett Field, California
Outline of Talk 1. Science Background for LADEE 2. LADEE Payload: 3 science instruments, 1 tech demo 3. LADEE Spacecraft 4. LADEE Launch Vehicle 5. LADEE Mission Profile 6. Schedule & Cost LADEE: Big Science 3
Science Background
LADEE: Science Focus Lunar Exosphere: A nearby example of a common type of atmosphere, the Surface Boundary Exosphere. Dust: Does evidence point to electrostatic lofting? In 2008, the door opened to investigate these questions: NASA Hq directed Ames Research Center to do the LADEE mission. LADEE: Big Science 5
LADEE Science Background
• 2003 NRC Decadal Survey: “New
Frontiers in the Solar System: An
Integrated Exploration Strategy”
• LEAG Roadmap Objective Sci-A-3:
Characterize the environment and
processes …in the lunar exosphere
• National Research Council (NRC)
report, “Scientific Context for the
Exploration of the Moon” (SCEM)
• 2011 NRC Decadal Survey: “Vision and
Voyages for Planetary Science in the
Decade 2013-2022”
– Execute LADEE mission
LADEE: Big Science 6
Exospheres and Dust
Surface Boundary Exospheres (SBEs) may be the most
common type of atmosphere in the solar system… Large Asteroids
& KBOs
Itokawa
Moon
Europa & Evidence of dust motion on
other Icy
asteroids and the Moon....
satellites
Io Rhea
LADEE CDR
May 17-20, Big
2011Science
ITAR RESTRICTED MATERIAL WARNING Eros
LADEE: 7 7
Lunar Exosphere – Measurements
Surface measurements: Ar and He Earth-based measurements: Na and K
40
LACE Ar Measurements
We know that Ar,
, Na and K
exist in the
exosphere.
LADEE CDR
ITAR RESTRICTED MATERIAL WARNING
May 17-20, Big
LADEE: 2011Science 8 8
SELENE/Kaguya Observations of Na
• UPI-TVIS instrument
• Viewed Na column
away from Moon
• Distribution
consistent with hot
source (2000 – 6000 K)
LADEE: Big Science 9 9
SELENE/Kaguya Observations of Na
• UPI-TVIS instrument
• Viewed Na column
away from Moon
• Distribution
consistent with hot
source (2000 – 6000 K)
• Density varies over 3-
month timescale
• Density appears to
decrease between 1st
quarter and 3rd quarter
LADEE: Big Science 10 10The Moon has a Sodium Tail!
• The Moon’s Na
exosphere doesn’t
stay put – it blows
away!
• At New Moon, the Na
atoms going
antisunward are
gravity-focused by
Earth.
• All-sky images from
Earth reveal this anti-
solar tail.
LADEE: Big Science 11 11The Moon has a Sodium Tail!
• The Moon’s Na
exosphere doesn’t
stay put – it blows
away!
• At New Moon, the Na
atoms going
antisunward are
Off-band subtracted gravity-focused by
Earth.
• All-sky images from
Earth reveal this anti-
solar tail.
LADEE: Big Science 12 12Lunar Exosphere – Solar Wind Input (Wieser et al, 2009) Chandrayaan Neutral Particles: >1 eV neutral hydrogen is lost. LADEE: Big Science 13 13
“Disappearing” Surficial H2O and OH
• Chandrayaan-1 M3, EPOXI and Cassini VIMS 3-μm observations.
• Presence of H2O and OH in/on surface grains:
o Signature deepest at high latitudes and off-noon local times.
o Where do OH, H2O go? Into exosphere? Polar cold traps?
Pieters et al Science 2009 Clark et al Science 2009
LADEE: Big Science LADEE ITAR RESTRICTED MATERIAL 14LCROSS Impact Results
Water Vapor and Water Ice in
Model Fit: 7.4% ± 5% by mass
Add other species:
CH4, CO2, SO2
LADEE: Big Science LADEE ITAR RESTRICTED MATERIAL 15 15Lunar Dust: Electrostatic Levitation?
Lunar Ejecta and Meteorites experiment (LEAM)
Terminators
Berg et al., 1976
• Apollo surface experiment LEAM detected dust activity correlated
with the lunar terminators
LADEE: Big Science 16Lunar Dust: Electrostatic Levitation? • Surveyor 7 images of lunar horizon glow (“LHG”) • Prevailing theory:
Lunar Dust – in Orbit?
McCoy and Criswell, 1974
Gene Cernan sketches from Apollo
Command Module
Apollo CM Trajectory
Dust?
• Eyewitness accounts of “streamers”
from Apollo command module
• Too bright to be meteoritic ejecta
• Exosphere and/or high altitude (50 km)
dust is one possibility
• Key goal if LADEE is to help resolve
this open question
LADEE: Big Science LADEE ITAR RESTRICTED MATERIAL 18 18LADEE Project Level Science Objectives
• LADEE Objective 1:
Determine the composition of the lunar atmosphere
and investigate the processes that control its
distribution and variability, including sources, sinks,
and surface interactions.
• LADEE Objective 2:
Characterize the lunar exospheric dust environment
and measure any spatial and temporal variability and
impacts on the lunar atmosphere.
LADEE:20
July Big–Science
23, 2010 LADEE ITAR RESTRICTED MATERIAL 19 19Let’s pause for questions
from the audienceLADEE Payload
LADEE Payload: 3 science, 1 tech demo
Neutral Mass Spectrometer (NMS) UV-Vis Spectrometer (UVS) Dust and
MSL/SAM Heritage LCROSS heritage exosphere
SMD - directed instrument
measurements
SMD - directed instrument
In situ measurement A. Colaprete
of exospheric NASA ARC
species
P. Mahaffy
NASA GSFC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX) Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage Technology demonstration
SMD - Competed instrument High Data Rate SOMD - directed instrument
M. Horányi Optical Comm
LASP
D. Boroson
MIT-LL
51-622 Mbps
LADEE: Big Science 22LADEE Neutral Mass Spectrometer
Measurement Concept:
• High-sensitivity quadrupole mass spectrometer,
mass range 1 - 150 Dalton and unit mass resolution.
• At 50-km or lower can detect helium, argon and
other species.
• Ultra high vacuum (UHV) materials and processing
used in the fabrication of NMS yield a substantial
improvement over background instrument noise
from Apollo era instruments, corresponding
increase in sensitivity of the measurement.
• The sensitivity is necessary to adequately
measure the low density atmosphere of the moon.
NMS Team:
Performance Data:
• Instrument PI: Dr. Paul Mahaffy/GSFC • Closed Source species: He, Ar, non-reactive neutrals
• Instrument Manager: Dr. Todd King/GSFC • Open Source species: neutrals and ions
• Instrument SE: Jim Kellog/GSFC • Mass Range: 2 - 150 Da
• Mass Resolution: unit mass resolution over entire range
• Sensitivity: 10-2 (counts per second) / (particles per cc)
Participating Organizations: • Mass: 11.3 kg
• NASA/GSFC • Volume: 23,940 cm3
• U. Michigan/Space Physics Research Lab • Envelope: 43.2 cm x 24.5 cm x 37.0 cm
• Power: 34.4 W average
• Battel Engineering • CDH interface: 422 differential
• AMU Engineering • Data Rate: 3.5 kbs
• Nolan Engineering • Data Volume: 8.5e6 bits per orbit
(assuming 40% duty cycle over a 113 min circular orbit)
LADEE: Big Science 23Mass spectrum from CoNTour NMS LADEE: Big Science 24
UV/Vis Spectrometer (UVS)
Measurement Concept:
• UVS includes UV-VIS Spectrometer, telescope,
solar diffuser, & bifurcated optical fiber
• UVS observations consists of limb and
occultation measurements
• Limb observations measure the lunar
atmosphere, & also measure limb dust by
measuring back- or forward-scattered sunlight
• Solar occultation observations measure lunar
atmospheric dust extinction from 0 to 50 km
Team: Performance Data:
• PI/PM: Dr. Tony Colaprete / ARC • In Limb mode measures atmospheric species
• Instrument SEs: Leonid Osetinsky / ARC including: K, Na, Al, Si, Ca, Li, OH, H2O
• By combining long integration times, UVS
and Ryan Vaughan / ARC
measures each specie to < current upper limits
• In limb mode measures dust (via scatter) at
Participating Organizations: concentrations as low as 10-4 per cc for r=100 nm
• NASA/ARC size particles.
• Aurora Design & Technology • In occultation mode measures dust (via
• Visioneering, LLC extinction) at concentrations as low as 10-4 per cc
for r=100 nm size particles down 300 meters alt.
• 3.98 kg
LADEE: Big Science • 14 W (average operation) 25
July 20 – 23, 2010Anticipated SNR Exospheric Species LADEE: Big Science 26
Lunar Dust Experiment (LDEX)
Measurement Concept:
• LDEX is an impact ionization dust detector
• Measures the mass of individual dust
grains with m ≥ 1.7x10-16 kg (radius rg ≥ 0.3
micron) for impact speeds ≈ 1.7km/s
• Also measures the collective current due to
grains below the threshold for individual
detection, enabling the search for dust
grains with rg ≈ 0.1 micron over the
terminators
Team:
PI: Mihaly Horanyi
Performance Data/Key Science
PM: Mark Lankton • Characterizes the dust exosphere by
mapping size and spatial distribution of
IS: Zoltan Sternovsky dust grains
SE: David Gathright • Measures relative contribution of dust
Participating Organization: sources: interplanetary vs. lunar origin.
Laboratory for Atmospheric and Space • Mass: 3.45kg (with reserves)
Physics, University of Colorado • Power: 6.11W peak, 5W ops (with
reserves)
• Data: 1kb/s
LADEE: Big Science Payload: 27 27How LDEX works…
ions
electrons
LADEE: Big Science 28LDEX Dust Accelerator data LADEE: Big Science 29
LLCD Technology Demo
Objectives/Features:
• Demonstrate laser communication between the
Earth and the LADEE spacecraft in lunar orbit.
NASA’s first step in developing high
performance laser communications systems for
future operational missions.
• Demonstrate major functions
– High bandwidth space to ground link using an optical
terminal
– Robust pointing, acquisition, tracking
LLCD has three primary parts: – Duplex communication day/night, full/new moon,
• Lunar Lasercom Space Terminal (LLST) high/low elevation, good/bad atmospherics
• Lunar Lasercom Ground Terminal (LLGT) – Time-of-flight measurements, as a by-product of the
• Lunar Lasercom Operations Center (LLOC) duplex communication, that could be built into a
high-accuracy ranging system
LLCD Team: Performance Data:
• Mission Manager: Hsiao Smith/GSFC • Space Terminal:
• Principal Investigator: Don Boroson/MIT/LL – 10 cm, 0.5W, 1.55um
• Co-Investigator: Mike Krainak/GSFC – 40-622 Mbps xmt, 10-20 Mbps rcv
– Duplex operation, fully gimbaled
• Mission Systems Engineer: Brendan
• Ground Terminal
Feehan/BAH
– Downlink Receiver
• Financial Manager: Debbie Dodson/GSFC » 4@40cm; 40-622 Mbps
Participating Organization: » Superconducting Nanowire Detector Arrays
• NASA/GSFC – Uplink Transmitter
• MIT/Lincoln Laboratory (LL) » 4@15cm, 10W; 10-20 Mbps
• Mass: 32.8 kg (with reserves), Power: 136.5W
LADEE: Big Science 30
July 20 – 23, 2010 Payload: 30LADEE Spacecraft
LADEE Common Bus Design History
MCR: 3-module, 2-
stage prop system
with SRM & bi-
1 prop, 4
Instruments,
Launch solo on
Award/Kickoff: 3-module, MinV
2-stage prop, 2 instruments,
Launch w/GRAIL
PDR: see major
PDR: see major changes
changes since
since KDP-B on subsequent
slide.
KDP-B on
subsequent slide.
Summary: Modular feature
of S/C bus has been
adaptable to change, but at
3 cost of constraining mass
Summary: Modular
margin available for PDR
feature of S/C bus
trade space.
has been adaptable
to change.
SRR/MDR: 4-module, single-stage
bi-prop system, 4 instruments, MinV
LADEE: Big Science 32LADEE: Ames Common Bus Spacecraft
Radiator Assembly
LDEX UVS
Bus Module
Payload Module
LLCD
NMS
Extension Modules
Propulsion Module
LADEE: Big Science 33Let’s pause for questions
from the audienceLaunch Vehicle
Launch Vehicle: LADEE and Minotaur V
PAF
Stage 5
Avionics
Cylinder
LADEE: Big Science 36LADEE Launch Vehicle: A Sporty Ride!
(Minotaur IV)
LADEE: Big Science 37LADEE Launch from Wallops Flight Facility LADEE: Big Science 38
Mission Profile
LADEE Post-launch: Phasing Loops
Nominal Launch Vehicle
Insertion 60 Re
60 Re
50 Re
43 Re
6.3 8.0 10.4 5.25
days days days days
Total Time of Flight: 30
Days
LADEE: Big Science 40LADEE Lunar Orbit Acquisition
Maneuver Timing Delta-V Duration
LOI-1 Periselene + 2 min 267 m/s 197 s (3 min 17 s)
(approx.)
LOI-2 LOI-1 + 2 Days 296 m/s 198 s (3 min 17 s)
LOI-3 LOI-1 + 4 Days 239 m/s 146 s (2 min 26 s)
LADEE: Big Science 41Commissioning Phase • Get science instruments working • Perform LLCD Ops LADEE: Big Science 42
Nominal Science Operations LADEE: Big Science 43
End of Mission! (Gravity always wins…)
Spacecraft and Orbit Maintenance:
• Planning key spacecraft activities
to maximize time in orbit and
science return
Science Campaign:
• Planning for high value science
opportunities at extremely low lunar
altitude
• Impact into far side terrain (avoid
legacy sites like Apollo, Luna,
Surveyor etc.)
LADEE: Big Science 44Schedule, Budget
• Launch slated for May, 2013
• Overall mission cost: $236M
• Payload: $37.4M
• Spacecraft: $74.6M
• Launch Vehicle: $63.4M
• Rest includes:
• Project mgmt, SE, S&MA, Science, PL
• Mission Ops, Ground systems, I&T, EPO
LADEE: Big Science 45LADEE: Mission of Many “Firsts”
LADEE :
• First mission with Ames “common
bus” architecture
• First flight of Minotaur V (modified
Peacekeeper ICBM w/add’l upper
stages)
• First deep space launch from
Wallops Flight Facility
• Laser communications technology
demonstration
Partners
• Ames does s/c development,
integration & test, mission operations
• GSFC is payload integrator, science
operations
• WFF is launch integrator
LADEE: Big Science 46Let’s pause for questions
from the audienceLADEE Lunar Education
Resources bringing lunar exploration into your classroom
Brian Day – NASA Lunar Science Institute
Brian.H.Day@nasa.govLunar 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 77058‐3696
Telephone: 281‐483‐8622
FAX: 281‐483‐4876
EMail: louis.a.parker@nasa.govWith 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.
•Solar radiation and particles play key roles in the production of the lunar atmosphere. •Your students can track the development of solar storms using data from student observations, observatories, and spacecraft. •http://son.nasa.gov/tass/
•Your students can help interpret data from NASA’s STEREO (Solar TErrestrial RElations Observatory) spacecraft. •http://www.solarstormwatch.com/
Impact Cratering: A major force in shaping the surface of the Moon
and a potentially important source for the lunar atmosphere.
http://quest/challenges/lcross/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
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.
Fresno Co. Juvenile Justice Campus
Student‐designed lunar impact simulator
•3 teams totaling 60 students creating designs around LCROSS Impact the Moon Challenge.
•Demonstrates continues utilization of resources.
•Successfully engaging a particularly challenging student audience.NASA Meteoroid Environment Office •It will be valuable to have as many
Lunar Impact Monitoring Program observations as possible of lunar
impacts during the LADEE mission.
Association of Lunar and Planetary Observers •This will facilitate studies examining
(ALPO) Lunar Meteoritic Impact Search Section possible correlations between changes
observed by LADEE and recorded
•Help lunar scientists determine the impact events.
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.http://www.nasa.gov/centers/marshall/news/lunar/photos.html
http://www.alpo-astronomy.org/Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime YanoInternational Observe the Moon Night (InOMN)
•World-wide celebration of the Moon and lunar science.
•Events held at NASA centers, museums, and schools.
•InOMN 2010 featured over 500 events in more than 50 countries.
•InOMN 2011 will occur on Saturday, October 8.
•NASA programming streamed to local events.
•Visit http://www.observethemoonnight.org/ to find an event near you
or to learn how to conduct your own event.Additional Reading from NASA Science News
NASA Mission to Study the Moon's Fragile Atmosphere: Overview of the
lunar atmosphere and the LADEE mission.
http://science.nasa.gov/science-news/science-at-nasa/2009/23oct_ladee/
Moon Storms: How results from from the Apollo missions provides evidence
of levitated lunar dust.
http://science.nasa.gov/science-news/science-at-nasa/2005/07dec_moonstorms/
Moon Fountains: Describes the "fountain model" of levitating moondust.
http://science.nasa.gov/science-news/science-at-nasa/2005/30mar_moonfountains/
Don't Breathe the Moondust: Examines the potential toxicity of lunar dust.
http://science.nasa.gov/science-news/science-at-nasa/2005/22apr_dontinhale/
Crackling Planets: The electrostatic hazards of lunar and Martian dust.
http://science.nasa.gov/science-news/science-at-nasa/2005/10aug_crackling/
En Route to Mars, the Moon: How learning to cope with lunar dust may help us in
future explorations of Mars.
http://science.nasa.gov/science-news/science-at-nasa/2005/18mar_moonfirst/Selected Online Resources LADEE – http://www.nasa.gov/ladee NASA Lunar Science Institute - http://lunarscience.arc.nasa.gov/ Exploring the Moon - http://www.nasa.gov/pdf/58199main_Exploring.The.Moon.pdf Lunar and Planetary Institute - http://www.lpi.usra.edu My Moon - http://www.lpi.usra.edu/mymoon/ Explore! - http://www.lpi.usra.edu/education/explore/ LRO - http://www.nasa.gov/lro Solar System Exploration at JPL - http://sse.jpl.nasa.gov Year of the Solar System - http://solarsystem.nasa.gov/yss/ Lunar Samples Program - http://curator.jsc.nasa.gov/lunar/index.cfm Moon Zoo - http://www.moonzoo.org/ Tracking a Solar Storm - http://son.nasa.gov/tass/ Solar Stormwatch - http://www.solarstormwatch.com/ LCROSS Cratering the Moon - http://quest/challenges/lcross/ Lunar Impact Monitoring - http://www.nasa.gov/centers/marshall/news/lunar/photos.html Association of Lunar and Planetary Observers (ALPO) - http://www.alpo-astronomy.org/ International Meteor Organization - http://imo.net/ American Meteor Society - http://www.amsmeteors.org/ International Observe the Moon Night - http://www.observethemoonnight.org/
Thank you to the sponsor of
tonight's Web Seminar:
This web seminar contains information about programs, products, and services
offered by third parties, as well as links to third-party websites. The presence of
a listing or such information does not constitute an endorsement by NSTA of a
particular company or organization, or its programs, products, or services.http://learningcenter.nsta.org
http://www.elluminate.com
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
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