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NASA Missions Paper
Steve Heck
Mission #1: LCROSS (Lunar CRater Observation and Sensing Satellite)
In early 1999, it became evident that the moon was holding a secret. Concentrated hydrogen signatures were
detected in the shadowed of lunar pole craters by NASA's Lunar Prospector (NASA 2010 c). If hydrogen is present,
so might water. This is a key discovery and would be vital for humans to return to explore the moon and beyond.
From this discovery, LCROSS was born. Its main mission goal was:
Mission Goal: Definitive answer to the question of lunar water (valuable recourse in the human
quest to explore the solar system) (NASA 2010 c)
To accomplish this goal, NASA determined the following main science objectives for the LCROSS mission
(NASA 2010 a):
1) Confirm the presence or absence of water ice in a permanently shadowed region on the moon.
2) Identify the cause of the hydrogen signatures detected at the lunar poles.
3) Determine the amount of water, if present, in the lunar regolith or soil.
4) Determine the composition of the regolith in one of the moon's permanently shadowed crater
NASA's studies from earlier Clementine and Lunar Prospector Missions determined the destination of the LCROSS
mission to that of the "Southern Lunar Pole Craters" (NASA 2010 e).
Note: Hydrogen rich areas are indicated by a dark purple region.
To accomplish these scientific objectives, LCROSS was to be launched in conjunction with the "Lunar
Reconnaissance Orbiter (LOR)" (NASA 2010 c). The basic concept was for the LCROSS (plus a shepherding
vehicle) and an Atlas V upper stage (Centaur) to enter into an elliptical lunar orbit. This would enable
LCROSS to align itself for lunar impact in a crater located in the southern pole region. Just prior to
impact, the spacecrafts separated with the Centaur leading the way. The lead spacecraft was to impact
the lunar surface four minutes prior to the arrival of LCROSS. Upon arrival, LCROSS would gather vital
scientific data from the cloud of debris created by the Centaur (NASA 2010 c).
To accomplish the mission, science and engineering research activities had to start with the unique
design of LCROSS. It was designed as a "fast-track, low-cost, companion mission" to the LRO. The
engineering concept was an "outside-the-box" type design to meet the science objectives of the
mission. It took advantage of commercially available satellite equipment, thus saving NASA research and
development funds (NASA 2010 d). Further, Diane Wooden's team at NASA Ames Research Center
develop procedures to capture the impact and analysis the results. The short-duration of the impact,
cloud debris plume, and flashes required close coordination (NASA 2010 b). A pre-impact mosaic of the
lunar crater photos and a post-impact mosaic were compared as was the cloud debris itself.
The analysis of the mission has begun with excellent results. A two part plume was analyzed, the upper
level plume contained vapor and fine dust while the lower plume ejecta curtain contained larger heavier
materials (Dino, 2009, July). Scientists have focused on the data from the spectrometers. They have
produced "the most definite information about the presence of water" on the lunar surface (Dino, 2009,
July). Anthony Colaprete (LCROSS project scientist/principal investigator - NASA Ames Research Center)
states: "Multiple lines of evidence show water was present...requires further analysis, but it is safe to
say Cabeus holds water (Dino, 2009, July). Mission goal accomplished.
For its scientific discoveries, LCROSS was the 2010 recipient of the Space Pioneer Award in Science and
Engineering for "Confirming the presence of water ice and other volatiles within a permanently shadow
region of Cabeus crater near the lunar south pole." (NASA 2010 c)
LCROSS INSTRUMENT CONFIGURATION
As shown above, instrumentation onboard LCROSS included nine instruments. They included: one visible
camera, two near infrared cameras, two mid-infrared cameras, one visible spectrometer, two near
infrared spectrometers, one total luminance photometer, and one data handling unit to collect data
from each instrument. This data was then sent to LCROSS Mission Control for analysis (NASA 2010 f).
Instrument
Purposes
(NASA 2010 f)
Visible Camera
Monitor ejecta cloud morphology. Determine visible grain properties
Near Infrared Cameras
Determine NIH grain properties. Water concentration maps
Mid-Infrared Cameras
Thermal Image. Measure thermal evolution of ejecta cloud. Remnant
crater image.
Visible Spectrometer
Visible emissions and reflectance spectrometry of vapor plume.
Measure emission H2O vapor dissociation.
Near Infrared Spectrometers
NIR emissions and reflectance spectrometry of vapor plume. Measure
broad H2O ice features. Occultation viewer to measure water vapor
Total Luminance Photometer
Measure total impact flash luminance, magnitude, and decay of
luminance curve.
Date Handling Unit
Instrument control and data acquisition.
Relevance to NASA's Current Goals and Vision of Exploration
The LCROSS mission is vital to NASA's Goals and Vision of Exploration. The discovery of water on the
lunar surface will enable astronauts of the near future to carry out our hopes and dreams of exploration.
Water on the moon helps solve some of the critical factors of fuel (hydrogen), oxygen, and water for
theses future endeavors. These findings are especially critical if we are to reach President Obama's goal
of crewed missions beyond the moon by 2025 (Sicloff, 2010, April). By this discovery and developing
processing of water on the moon crews will no longer be confined to taking these precious resources
from Earth (at great cost in mass and transportation vehicles). The LCROSS programs set the stage of
meeting the third goal of President Bush era vision (return to the moon by 2020 as a launching point for
missions beyond) (Bush, 2001, January). It will also be a key component of creating a permanent human
presence in space and will be a starting point for future exploration of the solar system.
Finally, on a personal note, I was at NASA's Ames Research Center and toured the LCROSS mission
center (received a crew patch too!). I was fortunate to meet the great scientists behind this endeavor. It
was an inspiring moment. Later, our 8th grade Science classes (130 students) watch as the LCROSS
mission hit the moon this last October. This was one of the highlights of the school year. It was a great
STEM class and lesson on how to inspire the next generation of explores. We continue to periodically
monitor the research of LCROSS.
References for Mission #1
Jonas Dino, NASA Ames Research Center (2009, November 13) LCROSS: "Impact Data Indicates Water on the
Moon"
Retrieved: July 23, 2010 from NASA
http://www.nasa.gov/mission_pages/LCROSS/main/prelim_water_results_prt.htm
NASA: AMES Research Center (2010 a) "LCROSS -Science Objectives"
Retrieved: July 23, 2010 from NASA
http://www.nasa.gov/mission_pages/LCROSS/main/index.html
NASA: LCROSS (2010 b) "NASA Developing Plans to Capture Lunar Impacts"
Retrieved: July 23, 2010 from NASA
http://www.nasa.gov/mission_pages/LCROSS/news/NASA_Developing_Plans_to_Capture_Lunar_Impacts.html
NASA Missions (2010 c) "LCROSS Overview"
Retrieved: July 23, 2010 from NASA
http://www.nasa.gov/mission_pages/LCROSS/overview/index.html
NASA: (2010 d) LCROSS "Spacecraft and System Description"
Retrieved: July 23, 2010 from NASA
http://lcross.arc.nasa.gov/spacecraft.htm
NASA: LCROSS (2010 e) "The Search for Water"
Retrieved: July 23, 2010 from NASA
http://www.nasa.gov/mission_pages/LCROSS/searchforwater/LCROSS_science_rational.html
NASA: (2010 f) LCROSS "Technical INFO: Instrument Systems"
Retrieved: July 23, 2010 from NASA
http://lcross.arc.nasa.gov/instruments.htm
President Bush, The White House (2004 January 14) "New Vision for Space Exploration"
Retrieved: July 24, 2010 from NASA
http://history.nasa.gov/Bush SEP.htm
Steven Sicloff, NASA John F Kennedy Space Center (2010, April 15) "President Outlines Exploration Goals, Promise"
Retrieved: July 24, 2010 from NASA
http://www.nasa.gov/about/obamaspeechfeature_prt.htm
Mission #2: Kepler (A Search for Habitable Planets)
The Kepler mission is one of NASA's first missions to realize both President Bush and Obama's goal of
seeking new frontiers of exploration (Bush, 2004, January & Sicloff, 2010, April). Kepler is designed as
"NASA's first mission capable of finding Earth-size and smaller planets around other stars" (NASA 2010
c). The basic mission is to find terrestrial planets in what is known as the "habitable zone." This is the
area around a star where a planet may have liquid water on its surface. Kepler was specifically designed
to reach out into the Milky Way Galaxy and determine what fraction of the Milky Way's stars might
contain these types of planet (NASA 2010 a). Kepler was launched on March 6, 2009 with the following
Mission Goal:
Mission Goal: To explore the structure and diversity of planetary systems (extrasolar), with
special emphasis on detection of Earth-size planets) (NASA 2010 b)
To accomplish this goal, NASA assigned the following Scientific Goals (NASA 2010 d & e):
1) Determine the frequency of terrestrial and larger planets in or near the habitation zone of a wide
variety of spectral types of stars.
2) Determine the distribution of sizes and orbital semi-major axes of these planets.
3) Estimate the frequency of planets and orbital distribution of planets in multiple-stellar systems.
4) Determine the distributions of semi-major axis, albedo, size, mass, and density of short-period planets.
5) Identify additional members of each photometrically discovered planetary systems using
complementary techniques.
6) Determine the properties of those stars that harbor planetary systems.
The design of the Kepler spacecraft incorporated a specific
instrument, a photometer, which provided a large field of view
needed to analyze a large number of stars. It is capable of
continuous and simultaneous monitoring of hundreds of thousands
of stars (NASA 2010 c). NASA scientists are able to increase the
stability of the photometer by focusing the Kepler photometer at
one single point of stars for the entire mission. This engineering
design not only increased stability, it also simplified the overall
spacecraft design (see picture at right) (NASA 2010 f). The
photometer is made up of 42 Charge Couple Devices (CCD's). CCD's
are not used to take pictures; they are integrated every 30 minutes
for data. Stars of an "R" magnitude of 16 are recorded and
transmitted to Earth once per month (NASA 2010 F).
By space basing this instrument, it insures the
precise data collection and the overall reliability
of Earth-like transit period throughout the
mission. It also avoids interruptions caused by
seasonal and day-night cycles and atmospheric
interference (see picture on left) (NASA 2010 a).
All stars must be continuously monitored to help
with the transitional periods that may last only a
fraction of an Earth day. This means the brightness of
a star or stars must be measured every few hours. To accomplish this, the field-of-view must remain clear or
unblocked (NASA 2010 c). Two requirements must be meet:
1) The Sun must be out of the elliptical plan.
2) The field-of-view must contain the greatest possible number of stars.
Once these requirements were met, the area of study in our Milky Way was determined. Kepler is now studying
the Cygnus and Lyra regions of our Galaxy (NASA 2010 d).
Relevance to NASA's Current Goals and Vision of Exploration
The Kepler mission reaches far beyond studying our moon and solar system. It is in a true sense a "Vision of
Exploration." While LCROSS is a great first step in the vision of exploration, Kepler is a tremendous leap in this
quest. Kepler is part of NASA's Discovery Program, mission number 10, to be exact. NASA's goal for this program is
to change how we explore the universe. With Kepler, as in other Discovery Programs, NASA promotes missions
that are comprised of teams of scientists, universities, laboratories, and small businesses to achieve the NASA
goals with cost caps (NASA 2010 a & b). This new approach relies on a Principal Investor (PI) to develop the science
objectives and the instrument payload. The PI brings the "mission team" together from original concept through
mission deployment and analysis. The overall responsibilities for the mission (cost, schedule, and performance
objectives) now rest with the PI and their team. This low coast approach, less than $425 million per mission
reduces development to launch time to about 12 to 24 months per mission (NASA 2010 a & b). This dynamic new
approach allows NASA not to have to concentrate on funding only missions in low Earth orbit. As President
Obama's vision is realized by NASA, a new flexible approach to exploration will be required. This flexible approach
will meet President Obama's vision of more commercial companies involved in the development and execution of
space missions (Sicloff, 2010, July). There will then be a balance between small missions like the Discovery
Program's Kepler, medium type missions of NASA's New Frontier Program, and the large NASA "Flagship"
programs. NASA's Science Mission Directorate defined the vision for scientific exploration; it includes "exploration
of our planet, other planets and planetary bodies, our star system in it's entirely and the universe beyond" (NASA
2010 a). Kepler and the Discovery Program help meet this goal (vision) by keeping mission cost low so funds may
be distributed to larger missions (human space flight), help develop new technologies, and increase public
awareness of NASA and exploration (NASA 2010 a &b)
References for Mission #2
NASA Discovery Program (2010 a) "Discovery Program: Description"
Retrieved: July 25, 2010 from NASA
http://discovery.nasa.gov/program.html
NASA Discovery Program (2010 b) "Discovery Mission Kepler"
Retrieved: July 25, 2010 from NASA
http://discovery.nasa.gov/kepler.html
NASA Missions (2010 c) "Kepler Overview"
Retrieved: July 25, 2010 from NASA
http://www.nasa.gov/mission_pages/kepler/overview/index.html
NASA Science (2010 d) "Kepler Science"
Retrieved: July 25, 2010 from NASA
http://www.nasa.gov/mission_pages/kepler/science/index.html
NASA Science (2010 e) "Scientific Goals"
Retrieved: July 25, 2010 from NASA
http://www.nasa.gov/Science/ScientificGoals/
NASA Spacecraft (2010 f) "Spacecraft and Instruments"
Retrieved: July 25, 2010 from NASA
http://www.nasa.gov/mission_pages/kepler/spacecraft/index-mission.html
President Bush, The White House (2004 January 14) "New Vision for Space Exploration"
Retrieved: July 24, 2010 from NASA
http://history.nasa.gov/Bush SEP.htm
Steven Sicloff, NASA John F Kennedy Space Center (2010, April 15) "President Outlines Exploration Goals, Promise"
Retrieved: July 24, 2010 from NASA
http://www.nasa.gov/about/obamaspeechfeature_prt.htm
Mission #3: DAWN - The Ninth of NASA’s Discovery Program Missions
NASA's DAWN mission and spacecraft is the ninth mission developed and launched under NASA's Discovery
Program. It is one of the first Discovery mission to use the new advanced technology of an Ion propulsion system
to power the spacecraft (NASA 2010 a). The Ion propulsion system uses solar electric Ion thrusters to maneuver.
Because of this technology, DAWN is able to carry a sufficient fuel load to reach and study both asteroids in a
single mission (NASA 2010 a). DAWN will travel to two of the oldest known asteroid in our solar system, Vesta in
2011 and Ceres in 2014. These two asteroids may hold the key to what the solar system was like 10 thousand years
ago. Hopefully, the DAWN mission will help scientist answer age old questions on the origins of our solar system
(NASA 2010 a). DAWN was launched in September of 2007. It flew past Mars for a gravity assist in February of
2009 and this August of 2010 it is due to arrive at Vesta (NASA 2010 e). The following is its mission goal.
Mission Goal: To characterize the conditions and processes of the solar system's earliest epoch by
investigating in detail two of the largest protoplanets remaining intact since their formations
(NASA 2010 a).
NASA's Jet Propulsion Laboratory (JPL) is the lead agency for the DAWN mission. They believe it has the potential
of being a "paradigm-shifting" mission of discovery. For example, the asteroid Ceres may have a thin atmosphere
and active "hydrological processing," while Vesta may have large magnetized rock formations, both central to
future flights to Mars and beyond (NASA 2010 a & e). To meet their high expectation, NASA's JPL has given DAWN
three specific scientific objectives:
1) Capture the earliest moments in the origin of the solar system enabling us to understand the conditions
under which these objects formed.
2) Determine the nature of the building block from which the terrestrial planets formed, improving our
understanding of this formation.
3) Contrast the formation and evolution of two small planets that follow different evolutionary paths so
that we understand what controls the evolution (NASA 2010 a & e).
Like other NASA Discovery Programs, DAWN was developed in
an innovative way to accomplish these objectives. It combines
state-of-the-art technologies, off the shelf components, and
spare parts from other missions. The Dawn spacecraft was also
designed with numerous backup systems to insure mission
success. The most innovative design feature is the Ion propulsion
system. Without the tested system (NASA Deep Space 1 mission)
DAWN would not be able to complete its mission (NASA 2010 f).
The map at left shows this mission's profile. This profile enables
DAWN to deliver its instrumentation package to two distinct
planetary bodies, thus being able to compare the differences in
one mission as opposed to two or more missions (NASA 2010 e).
DAWN carries three instrument systems to gather information from Ceres and Vesta.
The first is the Framing Camera. The camera is designed to acquire detailed images for
both navigation and science study of the planetoids. DAWN carries two such cameras
for redundancy (NASA 2010 g). The second instrument is a group of 21 sensors. These
sensors make up what is known as the Gamma Ray and Neutron Detector. Their
purpose is to identify the element composition of both Ceres and Vesta. By detecting
both Gamma Rays and Neutrons much will be analyzed about the surface area (i.e., is
water present on Ceres) (NASA 2010 g). The final instrument is the Visible and
Infrared Mapping Spectrometer. This instrument will detect what minerals exist on
both Ceres and Vista by comparing pictures (observations) from the planetoids to
those in the laboratory. As a side analysis, DAWN will detect variations in the gravity
fields of the planetoids thus providing clue on their mass and structure (NASA 2010 g).
Together these scientific instruments hope to answer the following:
1) What are the measurements of the planetoids (mass, shape, volume, and spin state)?
2) What are the elemental and mineral compositions?
3) What is the tectonic and thermal history, magnetism, and core size?
4) How does the internal structure compare between two different bodies? One cool and wet while the
other is hot and dry.
At the end of DAWN's decade long mission, scientists hope to determine one of the bid questions facing
exploration into the universe, that question being about the role of water in the evolutionary process or
development of planetoids/asteroids (NASA 2010 d).
Relevance to NASA's Current Goals and Vision of Exploration
President Obama in his Exploration Goals speech of April 15, 2010, put forth the challenge to begin crewed
missions to beyond the moon by 2025. He envisioned sending astronauts to an asteroid for the first time in history
and as a prerequisite to manned mission to Mars (Sicloff, 2010, April). The DAWN mission is the first key step in
realizing this goal. How important is this mission? NASA JPL scientists believe it is one of the most timely mission. It
will hopefully provide an understanding to the formation of the solar system. Further, that the mission will provide
needed data on water in the solar system, whether in the rocky (terrestrial) inner system or the cold frozen outer
solar system (NASA 2010 a). NASA JPL scientist further believe the DAWN mission "completes the first order of
exploring the inner solar system, addresses NASA's goal of understanding the origin and evolution of the solar
system and complements ongoing investigations of Mercury, Earth and Mars." (NASA 2010 a)
References for Mission #3
NASA Dawn-JPL (2010 a) "Mission Objectives"
Retrieved July 26, 2010 from NASA
http://dawn.jpl.nasa.gov/mission/goal_index.asp
NASA Dawn-JPL (2010 b) "Spacecraft"
Retrieved July 26, 2010 from NASA
http://dawn.jpl.nasa.gov/mission/spacecraft.asp
NASA Discovery Program (2010 c) "Discovery Program: Description"
Retrieved: July 26, 2010 from NASA
http://discovery.nasa.gov/program.html
NASA Discovery Program (2010 d) "Discovery Mission Dawn"
Retrieved: July 26, 2010 from NASA
http://discovery.nasa.gov/dawn.html
NASA Mission Dawn (2010 e) "Dawn at a Glance"
Retrieved: July 26, 2010 from NASA
http://www1.nasa.gov/mission_pages/dawn/mission/index_prt.html
NASA Mission Dawn (2010 f) "Spacecraft"
Retrieved: July 26, 2010 from NASA
http://www1.nasa.gov/mission_pages/dawn/spacecraft/index_prt.html
NASA Mission Dawn (2010 g) "Scientific Instruments"
Retrieved: July 26, 2010 from NASA
http://www1.nasa.gov/mission_pages/dawn/spacecraft/instruments_prt.html
President Bush, The White House (2004 January 14) "New Vision for Space Exploration"
Retrieved: July 24, 2010 from NASA
http://history.nasa.gov/Bush SEP.htm
Steven Sicloff, NASA John F Kennedy Space Center (2010, April 15) "President Outlines Exploration Goals, Promise"
Retrieved: July 24, 2010 from NASA
http://www.nasa.gov/about/obamaspeechfeature_prt.htm
END