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National A
eronautics andS
pace A
dm
inistrationM
ars
LG
-2000-10-481-HQ
The red planet M
AR
Shas inspired w
ild flights of imagi-
nation over the centuries,as well as intense scientific inter-
est. Whether fancied to be the source of hostile invaders of
Earth,the hom
e of a dying civilization,or a rough-and-tum
ble mining colony of the future,M
ars provides fertileground for science fiction w
riters,based on seeds plantedby centuries of scientific observations.
We know
that Mars is a sm
all rocky body once thought tobe very E
arth-like. Like the other “terrestrial”
planets—M
ercury,Venus,and E
arth—its surface has been changed
by volcanism,im
pacts from other bodies,m
ovements of
its crust,and atmospheric effects such as dust storm
s. Ithas polar ice caps that grow
and recede with the change of
seasons; areas of layered soils near the Martian poles sug-
gest that the planet’s climate has changed m
ore than once,perhaps caused by a regular change in the planet’s orbit.M
artian tectonism—
the formation and change of a planet’s
crust—differs from
Earth’s. W
here Earth tectonics involve
sliding plates that grind against each other or spread apartin the seafloors,M
artian tectonics seem to be vertical,w
ithhot lava pushing upw
ards through the crust to the surface.Periodically,great dust storm
s engulf the entire planet. The
effects of these storms are dram
atic,including giant dunes,w
ind streaks,and wind-carved features.
Scientists believe that 3.5 billion years ago,Mars experi-
enced the largest known floods in the solar system
. This
water m
ay even have pooled into lakes or shallow oceans.
Yet the central question about M
ars remains:w
here is thew
ater? Where did the ancient flood w
ater come from
,howlong did it last,and w
here did it go? At the present,M
arsis too cold and its atm
osphere is too thin to allow liquid
water to exist at the surface for long. W
e know that som
ew
ater exists today frozen in the polar ice caps,and enoughw
ater exists to form ice clouds,but the quantity of w
aterrequired to carve M
ars’great channels and flood plains isnot evident on the surface today. R
ecent images from
NA
SA’s M
ars Global Surveyor spacecraft suggest that
underground reserves of water m
ay break through the sur-face as springs. U
nraveling the story of water on M
ars isim
portant to unlocking its past climate history,w
hich will
help us understand the evolution of all planets,includingour ow
n. Water is also believed to be a central ingredient
for the initiation of life; the evidence of past or presentw
ater on Mars is expected to hold clues about past or pre-
sent life on Mars,as w
ell as the potential for life elsewhere
in the universe. And,before hum
ans can safely go to Mars,
we need to know
much m
ore about the planet’s environ-m
ent,including the availability of resources such as water.
Mars has som
e remarkable geological characteristics
including:the largest volcanic mountain in the solar sys-
tem,O
lympus M
ons (27 km high and 600 km
across); vol-canoes in the northern T
harsis region that are so huge theydeform
the planet’s roundness; and a gigantic equatorialrift valley,the V
alles Marineris. T
his canyon systemstretches a distance equivalent to the distance from
New
York to L
os Angeles; A
rizona’s Grand C
anyon could easi-ly fit into one of the side canyons of this great chasm
.
Mars also has tw
o small m
oons,Phobos and Deim
os.A
lthough no one knows how
they formed,they m
ay beasteroids snared by M
ars’gravity.
Fa
st Fa
cts
Nam
esakeR
oman G
od of War
Distance from
SunM
aximum
249 million km
Minim
um206 m
illion kmD
istance from E
arthM
aximum
399 million km
Minim
um56 m
illion kmR
otational Period
24.6 hoursE
quatorial Diam
eter6,786 km
Equatorial Inclination to E
cliptic25º.2
Gravity
38% of E
arth’sA
tmosphereM
ain Com
ponentC
arbon Dioxide
Pressure at Surface
4–8 millibars (vs 1,013 on E
arth)Tem
perature Range
-143ºC to +
17ºCM
oons (2)Phobos (Fear),21 km
mean diam
eterD
eimos (Panic),12 km
mean diam
eterR
ingsN
oneO
rbital Eccentricity
0.093O
rbital Inclination to Ecliptic
1º.85M
agnetic Field D
ensityL
ocalized at surface;not global.
Sig
nific
ant D
ate
s1965—
Mariner 4 m
ade first close-up pictures of the surface during flyby.
1969—M
ariner 6 and Mariner 7 flybys resulted in high resolution
images of the equatorial region and southern hem
isphere.1971—
Mariner 9 becam
e first satellite to orbit another planet.1973—
U.S.S.R
. Mars 3 and M
ars 5 first attempt to land on M
ars.1976—
U.S.A
. Vikings 1 and 2 orbited M
ars. Viking L
ander 1 provided first sustained surface science. V
iking Lander 2
discovered water frost on the surface.
1988—U
.S.S.R. probe Phobos returned detailed pictures of
Phobos.1996—
Launch M
ars Global Surveyor and M
ars Pathfinder.1997—
Mars Pathfinder lands on M
ars. Sojourner Rover
explores Ares V
allis area for 3 months.
1997—M
ars Global Surveyor m
aps the surface of Mars from
orbit.present
_________________________________R
eferences1)
Mars E
xploration:http://mars.jpl.nasa.gov/
2)Planetary Photo Journal:http://photojournal.jpl.nasa.gov/
3)V
iews of the Solar System
:http://ww
w.solarview
s.com/eng/m
ars.htm
4)Stardate,T
he University of Texas of A
ustin,McD
onald Observatory,
2609 University A
ve.,#3.118,Austin,T
X 78712
Mars 6 Inch M
ini Globes
FLA
GS
TA
FF, A
RIZ
ON
A
A
A
-6-8
-4 0
-2 2
6 4
81
21
01
4+
EL
EV
AT
ION
(kilo
meters)
A
North Hemisphere
Mars Digital Image Mosaicin a "Flower Petal" Projection for Making Globes
FLAGSTAFF, ARIZONA
Instructions for constructing a 6 inch mini globe1.) Cut out the north and south hemispheres. Make sure to remove all the white space surrounding the petals.2.) After adding a small amount of glue to the center of the north hemisphere, glue it onto the 6 inch globe.3.) Glue each petal down, starting at one end and proceeding in order around the 6 inch globe.4.) Place a small amount of glue on the south hemisphere petal labeled with an 'A'. Line up this petal with the corresponding northern hemisphere petal which is also labeled with an 'A' and glue to the 6 inch globe.5.) Glue down the center of the southern hemisphere.6.) Glue each remaining petal down, starting next to the petal already in place and proceeding in order around the 6 inch globe.
A
South Hemisphere
Mars Digital Image Mosaicin a "Flower Petal" Projection for Making Globes
FLAGSTAFF, ARIZONA
Instructions for constructing a 6 inch mini globe1.) Cut out the north and south hemispheres. Make sure to remove all the white space surrounding the petals.2.) After adding a small amount of glue to the center of the north hemisphere, glue it onto the 6 inch globe.3.) Glue each petal down, starting at one end and proceeding in order around the 6 inch globe.4.) Place a small amount of glue on the south hemisphere petal labeled with an 'A'. Line up this petal with the corresponding northern hemisphere petal which is also labeled with an 'A' and glue to the 6 inch globe.5.) Glue down the center of the southern hemisphere.6.) Glue each remaining petal down, starting next to the petal already in place and proceeding in order around the 6 inch globe.
A
Mars Topographyin a "Flower Petal" Projection for Making Globes
-6-8 -4 0-2 2 6 4 8 1210 14+
ELEVATION (ki lometers)
North HemisphereFLAGSTAFF, ARIZONA
Instructions for constructing a 6 inch mini globe1.) Cut out the north and south hemispheres. Make sure to remove all the white space surrounding the petals.2.) After adding a small amount of glue to the center of the north hemisphere, glue it onto the 6 inch globe.3.) Glue each petal down, starting at one end and proceeding in order around the 6 inch globe.4.) Place a small amount of glue on the south hemisphere petal labeled with an 'A'. Line up this petal with the corresponding northern hemisphere petal which is also labeled with an 'A' and glue to the 6 inch globe.5.) Glue down the center of the southern hemisphere.6.) Glue each remaining petal down, starting next to the petal already in place and proceeding in order around the 6 inch globe.
A
South Hemisphere
Mars Topographyin a "Flower Petal" Projection for Making Globes
-6-8 -4 0-2 2 6 4 8 1210 14+
ELEVATION (ki lometers)
FLAGSTAFF, ARIZONA
Instructions for constructing a 6 inch mini globe1.) Cut out the north and south hemispheres. Make sure to remove all the white space surrounding the petals.2.) After adding a small amount of glue to the center of the north hemisphere, glue it onto the 6 inch globe.3.) Glue each petal down, starting at one end and proceeding in order around the 6 inch globe.4.) Place a small amount of glue on the south hemisphere petal labeled with an 'A'. Line up this petal with the corresponding northern hemisphere petal which is also labeled with an 'A' and glue to the 6 inch globe.5.) Glue down the center of the southern hemisphere.6.) Glue each remaining petal down, starting next to the petal already in place and proceeding in order around the 6 inch globe.
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