International
partnership in lunar missions
Inaugural address by
His Excellency Dr A P J ABDUL KALAM
President of India
e-mail: presidentofindia@nic.in
Abstract:
I am delighted to participate in the 6th International Conference on
Exploration and Utilization of the Moon organized by the Physical
Research Laboratory,Ahmedabad.I
greet the organizers, eminent planetary exploration and space
scientists from India and
abroad,academicians,industrialists,engineers,entrepreneurs and
distinguished guests.I understand
that the International
Lunar Conference is a forum to discuss scienti fic results of the
ongoing and future space missions related to lunar exploration.This
conference will also be utilized to
develop understanding on various strategies,initiatives and missions
leading to a permanent
human presence on our Moon as the future objective.I am happy to note
that interactions that took
place in the earlier conferences have been bene ficial to participating
countries through the
intense sharing of scientific knowledge,data and hands-on mission
experiences of various space
agencies pursuing lunar exploration programmes.I find that nearly 100
scienti fic papers are being
presented in this conference and that the Moon missions being planned
and conducted by all the space
faring nations of the world are being presented,reviewed and
discussed.I note with excitement
that many key issues related to space science and Moon missions are
being addressed in this
conference.These deliberations are important for the world space
science community.This will
enable you to obtain a comprehensive picture of the goals and policies
of all nations striving
towards a common vision of space research,being made available for the
bene fit of all
mankind.Indeed this augurs well for progress towards universal peace
and harmony that is a cherished goal
of the people of the world as a whole.
Lunar science:
An overview
Stuart Ross Taylor
Department of Earth and Marine
Sciences, Australian National
University, Canberra
and Lunar and Planetary Institute, Houston
Texas, USA.
e-mail: Ross.Taylor@anu.edu.au
Abstract:
Before spacecraft exploration,facts about the Moon were restricted to
information about the lunar orbit,angular momentum and
density.Speculations about composition and
origin were unconstrained.Naked eye and telescope observations revealed
two major
terrains,the old heavily cratered highlands and the younger mostly
circular,lightly cratered maria.The
lunar highlands were thought to be composed of granite or covered with
volcanic ash-flows.The maria
were thought to be sedi-
ments,or were full of dust,and possibly only a few million years old.A
few perceptive observers such as Ralph Baldwin (Baldwin 1949)concluded
that the maria were filled
with volcanic lavas, but the absence of terrestrial-type central
volcanoes like Hawaii was a
puzzle. The large circular craters were particularly di fficult to
interpret.Some
thought,even after the Apollo flights,that they were some analogue to
terrestrial caldera
(e.g.,Green 1971),formed by explosive volcanic activity and that the
central peaks were
volcanoes.The fact that the craters were mostly circular was di fficult
to accommodate if they were due to
meteorite impact,as meteorites would hit the Moon at all angles.The
rilles were taken by many as de
finitive evidence that there
was or had been,running water on the lunar surface.Others such as Carl
Sagan thought that organic compounds were likely present (see Taylor
1975,p.111,note 139).
Origin of the
Earth–Moon system
E MGalimov A MKrivtsov
V. I. Vernadsky Institute of
Geochemistry and Analytical Chemistry,
Russian Academy of Sciences,
Kosygin str., 19, Moscow 119 991,
Russia.
∗e-mail: galimov@geokhi.ru
Capture of
interplanetary bodies in geocentric orbits
and early lunar evolution
Malapaka Shivakumar 1 ,2 , ∗and N
Bhandari 1 ,3 , ∗∗
1 Physical Research Laboratory,
Ahmedabad 380 009, India.
2 University of Hyderabad, Hyderabad
500 046, India.
3 Basic Sciences Research Institute,
Navrangpura, Ahmedabad 380 009,
India.
∗e-mail: shiva astro@yahoo.co.in
∗∗e-mail: bhandari@prl.ernet.in
Abstract:
During the accretion of planets such as Earth,which are formed by
collisional accretion of plan-etesimals,the probability of capture of
interplanetary bodies in
planetocentric orbits is calculated following the approach of Hills
(1973)and the n -body simulation,using
simplectic integration method.The simulation,taking an input mass equal
to about 50%of the
present mass of the inner planets,distributed over a large number of
planetoids,starting at 4 My
after the formation of solar system,yielded four inner planets within a
period of 30 My.None of
these seed bodies,out of which the planets formed,remained at this time
and almost 40%mass was
transferred beyond 100 AU. Based on these calculations,we conclude that
∼1 .4 times the mass of
the present inner planets was needed to accumulate them.The probability
of capture of planetoids
in geocentric orbits is
found to be negligible.The result emphasizes the computational di
fficulty in ‘probability of capture ’of planetesimals around the Earth
before the giant impact.This
conclusion,however,is in contradiction to the recent observations of
asteroids being frequently
captured in transient orbits around the Earth,even when the current
population of such
interplanetary bodies is smaller by
several orders of magnitude compared to the planetary accumulation era.
Determination
of lunar surface ages from crater
frequency–size distribution
B S Shylaja
Jawaharlal Nehru Planetarium,
Bangalore Association for Science
Education,
High Grounds, Bangalore 560 001,
India.
e-mail: taralaya@vsnl.com
Abstract: Crater size
–frequency distribution is one of the powerful techniques
to estimate the ages of planetary surfaces,especially from remote
sensing studies.This has been applied
to images of the Moon obtained from Clementine mission in 1994.Simple
techniques of
measurement of the diameter of the craters (in pixels)are used and
converted into linear
dimensions.Among the several maria studied,the results of Mare Humorum
and the central region of Mare
Imbrium are reported.The results are compared with age estimates from
other sources.
Low energy
trajectories for the Moon-to-Earth space
flight
V V Ivashkin
Keldysh Institute of Applied
Mathematics, Miusskaya Sq. 4, Moscow 125
047, Russia.
∗e-mail: Ivashkin@Keldysh.ru
Abstract: The Moon-to-Earth
low energy trajectories of ‘detour ’type are found
and studied within the frame of the Moon –Earth –Sun-particle
system.These trajectories use a
passive flight to the Earth from an initial elliptic selenocentric orbit
with a high aposelenium.The
Earth perturbation increases the particle selenocentric energy from a
negative value first to zero
and then to a positive one and therefore leads to a passive escape of
the particle motion from the
Moon attraction near the translunar libration point L 2 This results in
the particle flight to a
distance of about 1.5 million km from the Earth where the Sun
gravitation decreases the particle
orbit perigee distance to a small value that leads to the particle
approaching the Earth vicinity
in about 100 days of the flight.A set of the Moon-to-Earth ‘detour
’trajectories is de fined
numerically.Characteristics of these trajectories are presented.The
‘detour ’trajectories give
essential economy of energy (about 150 m/s in Delta V)relative to the
usual ones.
An analysis of
near-circular lunar mapping orbits
R V Ramanan摯瑬敳獩 and V Adimurthy
Aeronautics Entity, Vikram Sarabhai
Space Centre, Thiruvananthapuram
695 022, India.
∗e-mail: rv −ramanan@vssc.org
Abstract: Numerical
investigations have been carried out to analyse the evolution
of lunar circular orbits and the in fluence of the higher order
harmonics of the lunar gravity
field.The aim is to select the appropriate near-circular orbit
characteristics,which extend orbit
life through passive orbit maintenance.The spherical harmonic terms
that make major contributions
to the orbital behaviour are identi fied through many case studies.It is
found that for low
circular orbits,the 7th and the 9th zonal harmonics have predominant e
ffect in the case of orbits for
which the evolution is stable and the life is longer,and also in the
case of orbits for which the
evolution is unstable and a crash takes place in a short duration.By
analysing the contribution of the
harmonic terms to the orbit behaviour,the appropriate near-circular
orbit characteristics are
identi fied.
Microwave
brightness temperature imaging and
dielectric properties of lunar soil
Wu Ji 1, ∗,Li Dihui 1 ,Zhang Xiaohui
1 ,Jiang Jingshan 1 ,A T Altyntsev
2
and B ILubyshev 2
1 Center for Space Science and
Applied Research, Chinese Academy of
Sciences,
P.O. Box 8701, Beijing 100 080, China.
2 Institute of Solar Terrestrial
Physics, Siberia Branch of Russian
Academy of Sciences,
P.O. Box 4026, Irkutsk 664 033,
Russia.
1,2 China–Russia Joint Research
Center on Space Weather
∗e-mail: wuji@center.cssar.ac.cn
Abstract:
Among many scienti fic objectives of lunar exploration,investigations on
lunar soil become attractive due to the existence of He 3 and ilmenite
in the lunar soil and their
possible utilization as nuclear fuel for power generation.Although the
composition of the lunar surface
soil can be determined by optical and γ /X-ray spectrometers,etc.,the
evaluation of the total
reserves of He 3 and ilmenite within the regolith and in the lunar
interior are still not
available.In this paper,we give a rough
analysis of the microwave brightness temperature images of the lunar
disc observed using the NRAO 12 meter Telescope and Siberian Solar
Radio Telescope.We also
present the results of the microwave dielectric properties of
terrestrial analogues of lunar
soil and,discuss some basic relations between the microwave brightness
temperature and lunar soil
properties.
Energy
conversion evolution at lunar polar sites
James D Burke
The Planetary Society, 65 N. Catalina
Ave., Pasadena, CA 91106, USA.
e-mail: jdburke@its.caltech.edu
Abstract: Lunar polar
environments have many advantages from the standpoint of
energy supply to robotic and human surface bases.Sunlight is nearly
continuous and
always horizontal at peaks of perpetual light,while waste heat
rejection is aided by the
existence of cold,permanently shadowed regions nearby.In this paper a
possible evolution of
lunar polar energy systems will be described,beginning with small
robotic photovoltaic
landers and continuing into the development of increasingly powerful
and diverse energy
installations to provide not only electric power but also piped-in
sunlight,air conditioning and
high-temperature process heat.
Escape of
atmospheric gases from the Moon
Da Dao-an 1 ∗and Yang Ya-tian 2
1 Lanzhou Institute of Physics, 730
000 Lanzhou, Gansu, China.
2 Fujian Normal University, 350 007
Fuzhou, Fujian, China.
∗e-mail: dadaoan@sohu.com
Abstract: The escape rate of
atmospheric molecules on the Moon is
calculated.Based on the assumption that the rates of emission and
escape of gases attain equilibrium,the
ratio of molecular number densities during day and night,n 0 /n 0 ,can
be explained.The plausible
emission rate of helium and radioactive elements present in the Moon
has also been calculated.
The Clementine
mission – A 10-year perspective
Trevor C Sorensen 1, ∗and Paul D
Spudis 2
1 University of Kansas,Lawrence
KS,USA.
2 Applied Physics Laboratory,Laurel
MD,USA.
∗e-mail:sorenst@ku.edu
Abstract: Clementine was a
technology demonstration mission jointly sponsored by
the Department of Defense (DOD)and NASA that was launched on January
25th,1994.Its
principal objective was to use the Moon,a near-Earth asteroid,and the
spacecraft ’s Interstage
Adapter as targets to demonstrate lightweight sensor performance and
several innovative spacecraft
systems and technologies. The design,development,and operation of the
Clementine spacecraft and
ground system was per-
formed by the Naval Research Laboratory.For over two months Clementine
mapped the Moon, producing the first multispectral global digital map of
the Moon,the
first global topographic map, and contributing several other important
scienti fic
discoveries,including the possibility of ice at the lunar South
Pole.New experiments or schedule modi fications were made
with minimal constraints, maximizing science return,thus creating a new
paradigm for mission
operations.Clementine was
the first mission known to conduct an in-flight autonomous operations
experiment.After leaving the Moon,Clementine su ffered an onboard
failure that caused
cancellation of the asteroid rendezvous.Despite this setback,NASA and
the DOD applied the lessons
learned from the Clementine mission to later missions.Clementine set
the standard against
which new small spacecraft
missions are commonly measured.More than any other mission,Clementine
has the most in fluence (scienti fically,technically,and operationally)on
the lunar
missions being planned for the next decade.
Advances in
lunar science from the Clementine mission:
A decadal perspective
Mark Robinson摯瑬敳獩 and Miriam Riner
Center for Planetary Sciences,
Northwestern University, 1850 Campus
Drive, Evanston, IL 60208, USA.
∗e-mail:
robinson@earth.northwestern.edu
Abstract: The Clementine
spacecraft orbited the Moon and acquired science data
for 10 weeks in the Spring of 1994.During this time it collected global
11-band multispectral
images and near global altimetry. Select areas of the Moon were imaged
at 25 m/pixel in visible light and
60 m/pixel in thermal wavelengths.From these datasets a new paradigm
for the evolution of the
lunar crust emerged. The Moon is no longer viewed as a two-terrane
planet,the Apollo samples
were found not to represent the lunar crust as a whole,and the
complexity of lunar
crustal stratigraphy was further revealed.More than ten years later the
Clementine datasets continue to
signi ficantly advance lunar science and will continue to do so as new
measurements are returned
from planned missions such as Chandrayaan,SELENE,and Lunar
Reconnaissance Orbiter.This paper
highlights the scienti fic
research conducted over the last decade using Clementine data and
summarizes the in fluence of Clementine on our understanding of the Moon.
SMART-1 after
lunar capture: First results
and perspectives
B H Foing 1, ∗,G D Racca 2 ,A Marini
2 ,E Evrard 2 ,L Stagnaro 2 ,M
Almeida 1 ,
D Koschny 1 ,D Frew 1 ,J Zender 1 ,D
Heather 1 ,M Grande 3 ,J Huovelin
4 ,
H U Keller 5 ,A Nathues 5 ,J L Josset
6 ,A Malkki 7 ,W Schmidt 7 ,G
Noci 8 ,
R Birkl 9 ,L Iess 10 ,Z Sodnik 11 and
P McManamon 11
1 ESA Research and Scientific Support
Department, ESTEC/SCI-SR, Postbus
299, NL-2200 AG Noordwijk.
2 ESA Scientific Project Department,
ESTEC/SCI-PD.
3 Rutherford Appleton Labs, UK.
4 Helsinki Observatory.
5 Max-Planck-Institut f¨ ur
Aeronomie.
6 Space-X, Neuchatel.
7 Finnish Meteorology Institute.
8 LABEN SpA.
9 Astrium GmbH.
10 U. of Rome.
11 ESA Directorate of Technology,
ESTEC/TEC.
∗e-mail: Bernard.Foing@esa.int
Abstract:
SMART-1 is a technology demonstration mission for deep space solar
electrical propulsion and technologies for the future.SMART-1 is Europe
’s first lunar mission and
will contribute to developing an international program of lunar
exploration.The spacecraft was
launched on 27th September 2003,as an auxiliary passenger to GTO on
Ariane 5,to reach the Moon
after a 15-month cruise, with lunar capture on 15th November 2004,just
a week before the
International Lunar Confer-
ence in Udaipur.SMART-1 carries seven experiments,including three
remote sensing instruments used during the mission ’s nominal six
months and one year extension in
lunar science orbit.These instruments will contribute to key planetary
scienti fic
questions,related to theories of lunar origin and evolution,the global
and local crustal composition,the search for
cold traps at the lunar poles and the mapping of potential lunar
resources.
Chandrayaan-1:
Science goals
N Bhandari 1,2
1 Planetary Sciences and Exploration
Program, Physical Research
Laboratory, Navrangpura,
Ahmedabad 380 009, India.
2 Basic Sciences Research Institute,
Navrangpura, Ahmedabad 380 009,
India.
e-mail: bhandari@prl.ernet.in
Abstract:
The primary objectives of the Chandrayaan-1 mission are simultaneous
chemical,mineralogical and topographic mapping of the lunar surface at
high spatial
resolution.These data should enable us to understand compositional
variation of major elements,which in
turn,should lead to a better understanding of the stratigraphic
relationships between various litho
units occurring on the lunar surface.The major element distribution
will be determined using an
X-ray fluorescence spectro-
meter (LEX),sensitive in the energy range of 1 –10 keV where
Mg,Al,Si,Ca and Fe give their K α lines.A solar X-ray monitor (SXM)to
measure the energy spectrum of
solar X-rays,which are responsible for the fluorescent X-rays,is
included.Radioactive elements
like Th will be measured by its 238.6 keV line using a low energy
gamma-ray spectrometer
(HEX)operating in the 20 –250 keV region.The mineral composition will
be determined by a hyper-spectral
imaging spectrometer (HySI)sensitive in the 400 –920 nm range.The
wavelength range is
further extended to 2600 nm where some spectral features of the
abundant lunar minerals and water
occur,by using a near-infrared spectrometer (SIR-2),similar to that
used on the Smart-1
mission,in collaboration with ESA.A terrain mapping camera (TMC)in the
panchromatic band will provide
a three-dimensional
map of the lunar surface with a spatial resolution of about 5 m.Aided
by a laser altimeter (LLRI) to determine the altitude of the lunar
craft,to correct for spatial
coverage by various instruments, TMC should enable us to prepare an
elevation map with an accuracy of
about 10 m. Four additional instruments under international
collaboration are being
considered.These are: a Miniature Imaging Radar Instrument
(mini-SAR),Sub Atomic Re flecting
Analyser (SARA), the Moon Mineral Mapper (M3)and a Radiation Monitor
(RADOM).Apart from
these scienti fic payloads,certain technology experiments have been
proposed,which may
include an impactor which will be released to land on the Moon during
the mission. Salient features of the mission are described here.The
ensemble of
instruments onboard Chandrayaan-1 should enable us to accomplish the
science goals de fined
for this mission.
Launch strategy
for Indian lunar mission
and precision injection to the Moon
using genetic algorithm
V Adimurthy摯瑬敳獩 ,R V Ramanan S R
Tandon and C Ravikumar
Aeronautics Entity, Vikram Sarabhai
Space Centre, Thiruvananthapuram
695 022, India.
∗e-mail: v −adimurthy@vssc.org
Abstract: The Indian lunar
mission Chandrayaan-1 will have a mass of 523 kg in a
100 km circular polar
orbit around the Moon.The main factors that dictate the design of the
Indian Moon mission are to use the present capability of launch
vehicles and to achieve the
scienti fic objectives in the minimum development time and cost.The
detailed mission planning
involves trade-o ffstudies in payload optimization and the transfer
trajectory determination that
accomplishes these require-
ments.Recent studies indicate that for an optimal use of the existing
launch vehicle and space- craft systems,highly elliptical inclined
orbits are preferable.This
indeed is true for the Indian Moon mission Chandrayaan-1.The proposed
launch scenario of the Indian
Moon mission program and capabilities of this mission are described in
this
paper,highlighting the design challenges and innovations.Further,to
reach the target accurately,appropriate initial
transfer trajectory characteristics must be chosen.A numerical search
for the initial conditions
combined with numerical integration produces the near accurate solution
for this problem.The
design of such transfer trajectories is discussed in this paper.
Terrain mapping
camera for Chandrayaan-1
A S Kiran Kumar摯瑬敳獩 and A Roy
Chowdhury
Space Applications Centre, ISRO,
Ahmedabad 380 015, India.
∗e-mail: kiran@sac.isro.gov.in
Abstract: The Terrain Mapping
Camera (TMC)on India ’s first satellite for lunar
exploration,Chandrayaan-1, is for generating high-resolution
3-dimensional maps of the Moon.With
this instrument,a complete topographic map of the Moon with 5 m spatial
resolution and 10-bit
quantization will be available for scienti fic studies.The TMC will
image within the panchromatic
spectral band of 0.4 to 0 .µ with a stereo view in the fore,nadir
and aft directions of the
spacecraft movement and have a B/H ratio of 1.The swath coverage will
be 20 km.The camera is con figured
for imaging in the push broom-mode with three linear detectors in the
image plane.The camera
will have four gain settings to cover the varying illumination
conditions of the Moon.Additionally,a
provision of imaging with reduced resolution,for improving
Signal-to-Noise Ratio (SNR)in polar
regions,which have poor
illumination conditions throughout,has been made.SNR of better than 100
is expected in the ± 60 ◦latitude region for mature mare
soil,which is one of the
darkest regions on the lunar surface. This paper presents a brief
description of the TMC instrument.
Hyper-Spectral
Imager in visible and near-infrared
band
for lunar compositional mapping
A S Kiran Kumar摯瑬敳獩 and A Roy
Chowdhury
Space Applications Centre, ISRO,
Ahmedabad 380 015, India.
∗e-mail: kiran@sac.isro.gov.in
Abstract: India ’s first lunar
mission,Chandrayaan-1,will have a Hyper-Spectral
Imager in the visible and near-infrared spectral bands along with other
instruments.The
instrument will enable mineralogical mapping of the Moon ’s crust in a
large number of spectral channels.The
planned Hyper-Spectral Imager will be the first instrument to map the
lunar surface with the
capability of resolving the spectral region,0.4 to 0 .µ in 64
continuous bands with a
resolution of better than 15 nm and a spatial resolution of 80
m.Spectral separation will be done using a
wedge filter and the image will be mapped onto an area detector.The
detector output will be
processed in the front-end processor to generate the 64-band data with
12-bit quantization.This
paper gives a description of the Hyper-Spectral Imager instrument.
Lunar ranging
instrument for Chandrayaan-1
J AKamalakar摯瑬敳獩 ,K V S Bhaskar, A S
Laxmi Prasad, R Ranjith, K A Lohar,
R Venketeswaran and T K Alex
Laboratory for Electro-Optics
Systems, Indian Space Research
Organization (ISRO), Bangalore 560 058, India.
∗e-mail: kamalakar@leosisro.com
Abstract:
Lunar Laser Ranging Instrument (LLRI)proposed for the first Indian lunar
mission Chandrayaan-1 is aimed to study the topography of the Moon ’s
surface and its
gravitational field by precisely measuring the altitude from a polar
orbit around the Moon.Altimetry
data close to the poles of the Moon would also be available from the
instrument,which was not
covered by earlier missions. This instrument supplements the terrain
mapping camera and
hyper-spectral imager payloads on
Chandrayaan-1.The instrument consists of a diode pumped Nd:YAG pulsed
laser transmitter having 10 nsec pulse width and a receiver system.The
receiver system
features 17 cm diameter Ritchey –Chr ´etien collecting optics,Si
Avalanche Photo Detector
(APD),preampli fiers,constant fraction discriminators,time-of-flight
measurement unit and spacecraft
interface.Altimeter re-
solution of better than 5 m is targeted.The received signal strength of
LLRI depends on laser pulse backscatter from the Moon ’s surface.Moon
’s surface being a poor
re flector,the choice of receiver size and its type and the selection of
detector play an
important role in getting a good signal-to-noise ratio and in turn
achieving the target resolution.At
the same time,the spacecraft
puts a limitation on payload size and weight.This paper discusses the
proposed LLRI system for Chandrayaan-1 and signal-to-noise ratio
estimation.
High energy
X-γγγ ray spectrometer on the
Chandrayaan-1
mission to the Moon
J NGoswami 1, ∗,D Banerjee 1 ,N
Bhandari 1 ,M Shanmugam 1 ,Y B Acharya
1 ,
D VSubhedar 1 ,M R Sharma 2 ,C N
Umapathy 2 ,P Sreekumar 2 ,M Sudhakar
2 ,
L Abraham 2 and P CAgrawal 3
1 Physical Research Laboratory,
Ahmedabad 380 009, India.
2 Space Astronomy and Instrumentation
Division, ISRO Satellite Center,
Bangalore 560 017, India.
3 Tata Institute of Fundamental
Research, Mumbai 400 005, India.
∗e-mail: goswami@prl.ernet.in
Abstract:
The Chandrayaan-1 mission to the Moon scheduled for launch in late 2007
will include a high energy X-ray spectrometer (HEX)for detection of
naturally occurring emissions
from the lunar surface due to radioactive decay of the 238 Uand 232 Th
series nuclides in the
energy region 20 –250 keV.The primary science objective is to study the
transport of volatiles on the
lunar surface by detection of the 46.5 keV line from radioactive 210
Pb,a decay product of the
gaseous 222 Rn,both of which are members of the 238 U decay
series.Mapping of U and Th concentration
over the lunar surface,par-
ticularly in the polar and U –Th rich regions will also be attempted
through detection of prominent lines from the U and Th decay series in
the above energy range.The low
signal strengths of these emissions require a detector with high
sensitivity and good energy
resolution.Pixelated Cadmium – Zinc –Telluride (CZT)array detectors
having these characteristics will
be used in this experiment. Here we describe the science considerations
that led to this
experiment,anticipated flux and back- ground (lunar continuum),the
choice of detectors,the proposed payload
con figuration and plans for its realization.
Imaging and
power generation strategies for
Chandrayaan-1
Ananth Krishna摯瑬敳獩 ,N S Gopinath,N S
Hegde N K Malik
Control and Mission Area, ISRO
Satellite Centre, Bangalore 560 017,
India.
∗e-mail: akrishna@isac.ernet.in
Abstract:
The Chandrayaan-1 mission proposes to put a 550 kg lunarcraft into
Geostationary Transfer Orbit (GTO)using the Polar Satellite Launch
Vehicle (PSLV)which will
subsequently be transferred into a 100 km circular lunar polar orbit
for imaging purposes.In this
paper,we describe certain aspects of mission strategies which will
allow optimum power generation and
imaging of the lunar surface. The lunar orbit considered is circular
and polar and therefore nearly
perpendicular to the ecliptic
plane.Unlike an Earth orbiting remote sensing satellite,the orbit plane
of lunar orbiter is inertially fixed as a consequence of the very small
oblateness of the Moon.The
Earth rotates around the Sun once a year,resulting in an apparent
motion of Sun around this
orbit in a year.Two extreme situations can be identi fied concerning the
solar illumination of the
lunar orbit,noon/midnight
orbit,where the Sun vector is parallel to the spacecraft orbit plane
and dawn/dusk orbit,where the Sun vector is perpendicular to the
spacecraft orbit plane.This
scenario directly a ffects the solar panel con figuration.In case the
solar panels are not
canted,during the noon/midnight orbit, 100%power is generated,whereas
during the dawn/dusk orbit,zero power is generated.Hence for optimum
power generation,canting of the panels is
essential.Detailed analysis was carried
out to fix optimum canting and also determine a strategy to maintain
optimum power generation throughout the year.The analysis led to the
strategy of 180 ◦yaw
rotation at noon/midnight orbits and flipping the solar panel by 180 ◦at
dawn/dusk orbits.This also
resulted in the negative pitch face of the lunarcraft to be an anti-sun
panel,which is very useful for
thermal design,and further
to meet cooling requirements of the spectrometers.
In principle the Moon ’s surface can be imaged in 28 days,because the
orbit chosen and the payload swath provide adequate overlap.However,in
reality it is not
possible to complete the imaging in 28 days due to various mission
constraints like maximum
duration of imaging allowed keeping in view the SSR sizing and payloads
data input rate,time
required for downlinking the payload data,data compression requirements
and visibility of the
lunarcraft for the Bangalore DSN. In each cycle,all the latitudes are
swept.Due to the constraints
mentioned,only 60 ◦latitude arc coverage is possible in each orbit.As
Bangalore DSN is the only
station,half of the orbits in a day are not available.The longitudinal
gaps because of non-visibility are
covered in the next cycle by Bangalore DSN.Hence,in the first prime
imaging season only 25%of the
prime imaging zones are covered,and an additional three prime imaging
seasons are required
for a full coverage of the Moon in two years.Strategy is also planned
to cover X-ray payload
coverage considering swath and orbit shift.
Low energy
neutral atom imaging on the Moon with
the SARA instrument aboard
Chandrayaan-1 mission
Anil Bhardwaj 1 ∗,Stas Barabash 2
,Yoshifumi Futaana 2 ,Yoichi Kazama 2
,
Kazushi Asamura 3 ,David McCann 2 ,R
Sridharan 1 ,Mats Holmstrom 2 5 ,
Peter Wurz 4 and Rickard Lundin 2
1 Space Physics Laboratory, Vikram
Sarabhai Space Centre, Trivandrum
695 022, India.
∗e-mail: anil −bhardwaj@vssc.org
2 Swedish Institute of Space Physics,
Box 812, 98128, Kiruna, Sweden.
3 Japan Aerospace Exploration Agency,
Sagamihara, Kanagawa 229–8510,
Japan.
4 Physikalisches Institut, University
of Bern, CH-3012 Bern,
Switzerland.
5 Currently at NASA Goddard Space
Flight Center, Mail Code 612.2,
Greenbelt, MD 20771, USA.
Abstract:
This paper reports on the Sub-keV Atom Re flecting Analyzer
(SARA)experiment that will be flown on the first Indian lunar mission
Chandrayaan-1.The SARA is a low
energy neutral atom (LENA)imaging mass spectrometer,which will perform
remote sensing of
the lunar surface via detection of neutral atoms in the energy range
from 10 eV to 3 keV from
a 100 km polar orbit.In this report we present the basic design of the
SARA experiment and
discuss various scienti fic issues that will be addressed.The SARA
instrument consists of three major
subsystems:a LENA sensor (CENA),a solar wind monitor (SWIM),and a
digital processing unit
(DPU).SARA will be used to image the solar wind –surface interaction to
study primarily the
surface composition and surface magnetic anomalies and associated
mini-magnetospheres.Studies of lunar
exosphere sources and space weathering on the Moon will also be
attempted.SARA is the first
LENA imaging mass spectrometer of its kind to be flown on a space
mission.A replica of
SARA is planned to fly to Mercury onboard the BepiColombo mission.
Lunar-A
mission: Outline and current status
H Mizutani摯瑬敳獩 ,A Fujimura, S Tanaka,
H Shiraishi and T Nakjima
Institute of Space and Astronautical
Science, Japan Aerospace
Exploration Agency, Yoshinodai 3-l-l,
Sagamihara, Kanagawa 229 8510, Japan.
∗e-mail:
mizutani@planeta.sci.isas.ac.jp
Abstract: The scienti fic
objective of the Lunar-A,Japanese Penetrator Mission,is
to explore the lunar interior by seismic and heat-flow experiments.Two
penetrators containing two
seismometers (horizontal and vertical components)and heat-flow probes
will be deployed from a
spacecraft onto the lunar surface,one on the near-side and the other on
the far-side of the
moon.The data obtained by the penetrators will be transmitted to the
earth station via the Lunar-A
mother spacecraft orbiting at
an altitude of about 200 km.
The spacecraft of a cylindrical shape,2.2 m in maximum diameter and 1.7
m in height,is designed to be spin-stabilized.The spacecraft will be
inserted into an elliptic
lunar orbit,after about a half- year cruise during which complex
manoeuvering is made using the
lunar-solar gravity assist.After lunar orbit insertion,two penetrators
will be separated from the
spacecraft near perilune,one by one,and will be landed on the lunar
surface.
The final impact velocity of the penetrator will be about 285 m/sec;it
will encounter a shock of about 8000 G at impact on the lunar
surface.According to numerous
experimental impact tests using model penetrators and a lunar-regolith
analog target,each
penetrator is predicted to penetrate to a depth between l and 3
m,depending on the hardness and/or
particle-size distribution
of the lunar regolith.The penetration depth is important for ensuring
the temperature stability of the instruments in the penetrator and heat
flow
measurements.According to the results of the Apollo heat flow
experiment,an insulating regolith blanket of only 30 cm
is su fficient to dampen out about 280 K lunar surface temperature
fluctuation to < The seismic observations are expected to provide key
data on the size
of the lunar core,as well as data on deep lunar mantle structure.The
heat flow measurements at two
penetrator-landing sites will also provide important data on the
thermal structure and
bulk concentrations of heat- generating elements in the Moon.These data
will provide much stronger
geophysical constraints on the origin and evolution of the Moon than
has been obtained so far. Currently,the Lunar-A system is being
reviewed and a more robust system
for communication between the penetrators and spacecraft is being
implemented according
to the lessons learned from Beagle-2 and DS-2 failures.More impact
tests for penetrators onto a
lunar regolith analogue target will be undertaken before its launch.
SELENE project
status
Konishi Hisahiro 1, ∗, Manabu Kato 2
, Susumu Sasaki 2 , Yoshisada
Takizawa 1
and Hitoshi Mizutani 1
1 Institute of Space and
Astronautical Science, Japan Aerospace
Exploration Agency (JAXA),
2-1-1 Sengen, Tsukuba, Ibaraki
305-8505, Japan.
2 Institute of Space and
Astronautical Science, Japan Aerospace
Exploration Agency (JAXA),
3-1-1 Yoshinodai, Sagamihara,
Kanagawa 229-8510, Japan.
∗e-mail: konishi.hisahiro@jaxa.jp
Abstract: SELENE
(Selenological and Engineering Explorer) project started as a
joint mission of the former ISAS (Institute of Space and Astronautical
Science) and the former
NASDA (National Space Development Agency: the two organizations were
merged into JAXA in
2002) of Japan in 1998. The launch target is rescheduled for 2006 due
to delay of completion of
launch vehicle, H-IIA. The SELENE project is now under a sustained
design phase. The flight
model components were
manufactured, and the interface tests between the bus-system and the
mission instruments were completed by the end of March 2004. The
functional checks and
calibration for the flight model components are being carried out at
present. From the beginning of
2005, the final assembly tests will start.
Japanese lunar
robotics exploration by co-operation
with lander and rover
Takashi Kubota 1, ∗,Yasuharu Kunii 2
,Yoji Kuroda 3 and Working Group
1 ISAS/JAXA, 3-1-1, Yoshinodai,
Sagamihara, Kanagawa 229-8510, Japan.
2 Chuo University, 1-13-27, Kasuga,
Bunkyo-ku, Tokyo 113-8551, Japan.
3 Meiji University, 1-1-1,
Higashi-mita, Tama-ku, Kawasaki 214-8571,
Japan.
∗e-mail: kubota@nnl.isas.jaxa.jp
Abstract: Unmanned mobile
robots for surface exploration of the Moon or planets
have been extensively studied and developed.A lunar rover is
expected to travel safely in a
wide area and explore in detail. Japanese lunar robotics exploration is
under study to conduct an
unmanned geological survey in the vicinity of central peaks of impact
craters for investigation of the
sub-surface materials.This will give us the key information to study
the lunar inner structure and
understand the Moon ’s origin
and evolution as well as to investigate the evolution of magma ocean
and later igneous processes.To carry out the geological exploration in
the central peak,lander and
rover co-operative exploration is proposed.The working group has been
conducting feasibility study of
advance technologies.This paper addresses an overview of lunar
exploration with lander and rover
and also enumerates future technologies to be established.
The rover R&D group has developed an innovative science micro rover
with a new mobility system and a lightweight manipulator.The design and
implementation of a
science rover for the near future lunar missions requiring long
traverses and scienti fic
observations are described and some experimental results are presented.
Scientific
objectives and payloads of Chang’E-1
lunar satellite
Sun Huixian 1, ∗,Dai Shuwu 1 ,Yang
Jianfeng 2 ,Wu Ji 1 and Jiang
Jingshan 1
1 Center for Space Science and
Applied Research (CSSAR), Post Box 8701,
Beijing 100 080, China.
2 Xi’an Institute of Optics and
Precision Mechanics, Chinese Academy of
Sciences (CAS), Xi’an 710 068, China.
∗e-mail: shxian@nc.poac.ac.cn
Abstract: China plans to
implement its first lunar exploration mission Chang ’E-1
by 2007.The mission
objectives are
•to obtain a three-dimensional stereo image of the lunar surface,
•to determine distribution of some useful elements and to estimate
their abundance,
•to survey the thickness of lunar soil and to evaluate resource of 3 He
and
•to explore the environment between the Moon and Earth.
To achieve the above mission goals,five types of scienti fic instruments
are selected as payloads of the lunar craft.These include stereo camera
and spectrometer
imager,laser altimeter,microwave radiometer,gamma and X-ray
spectrometers and space environment monitor
system.In order to collect,process,store and transmit the scienti fic
data of various
payloads a special payload data management system is also included.In
this paper the goals of Chang
’E-1 and its payloads are described.
Space operation
system for Chang’E program
and its capability evaluation
Yu Zhi-jian Lu Li-chang Liu Yung-chun
and Dong Guang-liang
Beijing Institute of Tracking and
Telecommunications Technology, P.O.
Box 5131, Beijing 100 094, China.
∗e-mail: csaspace@163bj.com
Abstract: Space operation for
China ’s first lunar exploration program,Chang ’E
will be provided by the S-band aerospace Telemetry,Tracking and Command
(TT&C)network
designed for China ’s manned space program.This is undoubtedly a great
challenge to the
ground TT&C system.The largest antennas of China ’s S-band
aerospace TT&C network has an
aperture of only 12 m.A series of technical measures have been taken
into the designing of the
spacecraft-ground TT&C system to
ensure that such antennas can communicate with Chang ’E-1 lunar probe
400,000 km away.These include installation of high-gain directional
antennae and medium-gain
omni-directional antennae for the probe,adding channel encoding to the
downlink channel,using
both high and low data rates for information transmission and upgrade
and design of ground
equipment terminals.Among them,the omni-directional antenna will
operate in the earth-ground
transfer orbit phase and the directional antenna will operate in the
lunar orbit phase.These
measures satisfy the spacecraft- ground link and program design
requirements.
To provide accurate navigation for the probe during its Earth –Moon
flight and initial lunar orbiting flight,China ’s VLBI system designed
for astronomical
observations,will also be used besides the ranging and range rate
measurement capabilities of the S-band
TT&C network.The purpose is to provide 100 m accuracy in position
determination during lunar
orbit.This paper describes the system design,technical
challenges,solutions and capability
evaluation of space operation for Chang ’E-1.
Luna-Glob
project in the context of the past
and present lunar exploration in Russia
E MGalimov
V.I. Vernadsky Institute of
Geochemistry and Analytical Chemistry,
Russian Academy of Sciences,
Kosygin Str., 19, Moscow 119 991,
Russia.
e-mail: galimov@geokhi.ru
Abstract:
The Russian Luna-Glob project has been conceived with a view to
understand the origin of the Earth –Moon system.The objectives and main
features of the Luna-Glob
mission,which will mainly study the internal structure of the Moon by
seismic instruments,are
described in the context of the past and current program of lunar
exploration in Russia.
Analysis of
optimal strategies for soft landing
on the Moon from lunar parking orbits
R V Ramanan and Madan Lal
Aerospace Flight Dynamics Group,
Vikram Sarabhai Space Centre,
Thiruvananthapuram 695 022, India.
∗e-mail: rv −ramanan@vssc.org
Abstract:
Optimal trajectory design of a probe for soft landing on the Moon from
a lunar parking orbit by minimizing the fuel required is obtained.The
problem is formulated as
an optimal control problem with the thrust direction being the control
variable.Using the maximum
principle of Pontryagin, the control variable is expressed as a
function of co-state variables
and the problem is converted into a two-point boundary value
problem.The two-point boundary value
problem is solved using
an optimization technique,i.e.,controlled random search.The strategies
such as
•direct landing from a lunar parking orbit using powered braking
•direct landing from an intermediate orbit using powered braking
•by executing powered braking in two phases:through horizontal braking
and vertical landing are analyzed and an optimal strategy that achieves
the goals is
suggested.Also,appropriate design parameters are selected using this
analysis.
Telerobotic
exploration and development of the Moon
B L Cooper 1, ∗,B Sharpe 2 ,D Schrunk
3 and M Thangavelu 4
1 Oceaneering Space
Systems,Houston,Texas,USA.
2 Independent Lunar Development
Planner,St.Louis,MO,USA.
3 Quality of Laws
Institute,Poway,CA,USA.
4 Space Exploration Architectures
Concept Synthesis Studio,Division of
Astronautics and
Space Technology and School of
Architecture,University of Southern
California,USA.
∗e-mail:bcooper138@houston.rr.com
Abstract: There has
been a debate for the last thirty years about the relative
merits of human versus robotic systems and we argue here that both are
essential components for
successful lunar exploration and development.We examine the role of
robots in the next phases of
exploration and human development of the Moon.The historical use of
robots and humans in exploration
is discussed,including Apollo-era exploration,International Space
Station,and deep-water
petroleum exploration.The technological challenges of lunar operations
are addressed in the
context of how robotic systems can be designed for robust and flexible
operations.System design
recommendations are given based on the lessons learned from terrestrial
and space robotics.