The size of Mars can not be given in one set of
numbers. Scientists describe a planet by many
radius is 3,389.5 km.
circumference is 21,344 km.
volume is 1.63116 X 1011 km3.
mass is 6.4169 x 1023 kg.
Mars has 53% of the diameter of Earth. It has
about 38% of the surface area of Earth.
Size of Mars compared to Earth.
The Red Planet
Mars has a reddish appearance, and so that’s
why it was called the Red Planet. It was Mars’
appearance that inspired people to give it its
current name. It would be safe to presume that
the color of war, red, was the basis for it.
Al-Qahira - Arabic,
Ares - Greek
Auqakuh - Quechua
Bahram - Persian
Harmakhis - Ancient
Her Desher - Egyptian
Hrad - Armenian
Huo Hsing - Chinese
Kasei - Japanese
Labou - French
Ma'adim - Hebrew
Maja - Nepali
Mamers - Oscan
Mangala - Sanskrit
Marte - Spanish
Mawrth - Welsh
Nirgal - Babylonian
Shalbatana - Akkadian
Simud - Sumerian
Tiu - Old English
The atmosphere of Mars is relatively thin and
is composed of carbon dioxide (95.32%).
There has been interest in studying its
composition since the detection of trace
amounts of methane, which may indicate the
presence of life on Mars, but may also be
produced be a geothermal process, volcanic or
The largest of the volcanoes in the Tharsis Montes
region, as well as all known volcanoes in the solar
shield volcano 624 km (374 mi) in diameter, 25 km
(16 mi) high, and is rimmed by a 6 km (4 mi) high
A caldera 80 km (50 mi) wide is located at the
The volume of Olympus Mons is about 100 times
larger than that of Mauna Loa ( The largest
volcano on earth).
The entire chain of Hawaiian islands (from Kauai
to Hawaii) would fit inside Olympus Mons.
The main difference between the volcanoes on
Mars and Earth is their size.
Volcanoes in the Tharsis region of Mars are 10 to
100 times larger than those anywhere on Earth.
The lava flows on the Martian surface are observed
to be much longer, probably a result of higher
eruption rates and lower surface gravity.
The crust on Mars doesn't move the way it does on
The crust remains stationary and the lava piles up in
one, very large volcano.
compared to Arizona.
The image you
This is what the
look like shortly
after sunrise from
an altitude of 35
VallesMarineris is 2500 miles long, 310 miles wide
by 4.3 miles deep.
It is actually a system of several interconnected
canyons, each with different names and distinctive
It was named after Mariner 9 because it was the
first to image it.
VallesMarineris was not carved by running water
– it is a gigantic fracture in Mars’ crust. Pulling
apart of the surface formed the main portion of the
canyon system. Massive landslides are also present
in the canyons.
This shaded relief painting (to the
left) is based on Viking Orbiter
images and shows the
VallesMarineris trough system
with a map of the United States
for scale. VallesMarineris is 4000
kilometers long, nearly enough to
stretch from New York to
reaches a maximum depth of 10
Launched in August 2007
The Phoenix Mars Mission was led by University
of Arizona. is the first in NASA's Scout Program.
Phoenix is designed to study the history of water
and habitability potential in the Martian arctic's
Prolific photographer that shot over 25000 pictures
Phoenix is officially dead because it ran out of
battery power from no sun light.
One of the first suface
images taken by the
Left: Covering in place
Right: Covering pushed aside.
Though they were more famous for what they
discovered and mapped out with Earth’s
moon, these two discovered the geography of
Mars. They had made a simple map of the
2001 Mars Odyssey (launch: April 7, 2001; arrival: October 24,
2001) –The spacecraft has taken over 130, 000 images and
it continues to collect and send information to Earth.
The information includes Martian geology, climate and
2003 Mars Exploration
Mars Reconnaissance Orbiter
Mariner 3– Mariner 3 did not make it to Mars.
Mariner 6-7 –Flew around Mars together, missed northern
volcanoes by chance, and discovered Mars’ dark features, seen
from Earth, were not canals.
Mariner 8-9 – Mariner 8 failed during launch. Mariner 9
functioned in Martian Orbit for nearly a year. Completed its final
transmission October 27, 1972.
Viking 1 & 2 – First two successful U.S. spacecrafts to land on the
surface of Mars.
Mars Observer Global Surveyor
Polar Lander, Deep Space 2
Vast volcanic plateau centered near the equator in
Mars’ western hemisphere.
Home to the largest volcanoes in the solar system:
the three enormous shield volcanoes,Arsia
mons,Pavonis mons, and Ascraeus mons, which
are collectively known as the tharsis montes.
The tallest volcano on the planet, Olympus Mons,
is often associated with the Tharsis region but is
actually located off the western edge of the
The name Tharsis is the Greco-Latin
transliteration of the biblical tarshish, the land at
western extremity of the known world.
Thermal image of the Tharsis Region
Differing values have been reported for the
average temperature on Mars, with a common
value being −55 °C (−67 °F)
Actual temperature measurements from the
Viking Landers range from −17.2 °C (1.0 °F) to
−107 °C (−161 °F).(20C) decrease in average
surface temperature, and a moderate (30C)
increase in upper atmosphere temperature.
Temperatures varying from year-to-year
estimated from the Viking Orbiter Infrared Thermal
Mapper data; this gives extremes from a warmest of 27
°C (81 °F) to −143 °C (−225 °F) at the winter polar caps.
Mars possesses ice caps at both poles, which mainly
consist of water ice; however, there is frozen carbon
dioxide (dry ice) present on their surfaces.
Dry ice accumulates in the northern polar region
(planum boreum) in winter only, subliming completely
in summer, while the south polar region additionally
has a permanent dry ice cover up to eight meters (25
Both polar caps show spiral troughs, which were
formerly believed to form as a result of differential
solar heating, coupled with the sublimation of ice and
condensation of water vapor
Liquid water cannot exist on the surface of Mars due to low
atmospheric pressure, except at the lowest elevations for
The volume of water ice in the south polar ice cap, if melted,
would be sufficient to cover the entire planetary surface to a
depth of 11 meters.
Landforms visible on Mars strongly suggest that liquid
water has at least at times existed on the planet's surface.
Huge linear swathes of scoured ground, known as outflow
channels, cut across the surface in around 25 places.
These are thought to record erosion which occurred during
the catastrophic release of water from subsurface aquifers,
though some of these structures have also been
hypothesized to result from the action of glaciers or lava.
The two polar ice caps appear to be made
largely of water.
A permafrost mantle stretches from the pole to
latitudes of about 60°.
The bigger moon of the two of them is
Phobos. It measures 27 X 21 X 19 km and is
oblong shaped. It orbit around Mars lasts Phobos may not have as much
dust and debri on its surface is
less than a Martian day, bout 7.3 hours.
The orbit makes the moon look like it rises because of its close orbit to Mars
in the west and sets in the east. With
interesting parallel grooves about 150 m where the planet's gravity wold
long ad 25 meters deep, Phobos is heavily tend to pull debris off the moon.
cratered. The grooves seem to come from Deimos has an even lower
the largest grater to an odd shaped area on
the other side of the moon. This shows that escape velocity than Phobos
does with only 12 m/sec.
the grooves may have formed with the
impact of the largest
Deimos is covered by dust
which makes it look like it has
little surface area. The dust fills
craters and covers some surface
Both moons are probably about 2 billion years
old and appear to have a composition very
similar to carbonaceous chondrites. Since
carbonaceous chondrites form in the asteroid
belt, it is considered highly probable that both
Phobos and Deimos are captured asteroids.
Both moons have a density of about 2 g/cu.
cm, lower than Mars 4 g/cubic cm. This, along
with their appearance makes astronomers
think that Phobos and Deimos are more similar
to the asteroids than Mars.
Also called North Polar Basin is a large basin in
the northern hemisphere of Mars that covers
40% of the planet
One possible explanation for the basin's low,
flat and relatively crater-free topography is that
the basin was formed by a single large impact.
Two simulations of a possible impact sketched
a profile for the collision: low velocity (6 – 10
km/s), oblique angle and diameter 1,600 - 2,700
Topology map of Mars.
Launch Date: November 28, 1964
It was the fourth in a series used to explore Mars in a flyby mode.
It was designed to take scientific close-up observations of the
planet and send them back to Earth. It passed Mars at a distance of
9,869 kilometers and recorded the first close-up picture of Mars. It
has taken 22 pictures and out of those, Mariner's TV camera has
scanned about 1% of the Martian surface, showing that it had
ancient craters of varying sizes.
Mariner 4 had actually proved that Percival Lowell's observations
with his telescope in 1890, the canals, were just optical illusions.
Natural waterways may be evident in some regions, though.
Measurements of atmospheric density and the interplanetary
medium are other experiments performed by the spacecraft.
December 20, 1967, the operations of the spacecraft have stopped.
described as the "Red Planet" due to iron oxide
on its surface which gives it a reddish
Mars is a terrestrial planet with a thin
atmosphere, having surface features
reminiscent both of the impact craters of the
Moon and the volcanoes, valleys, deserts, and
polar ice caps of Earth.
Its apparent magnitude reaches −3.0 a
brightness surpassed only by Jupiter, Venus,
the Moon, and the Sun.
Optical ground based telescopes are typically limited
to resolving features about 300 km (186 miles) across
when Earth and Mars are closest, because of Earth's
Mars' average distance from the Sun is roughly 230
million km and its orbital period is 687 (Earth)
The solar day on Mars is only slightly longer than
an Earth day: 24 hours, 39 minutes, and 35.244
A Martian year is equal to 1.8809 Earth years, or 1
year, 320 days, and 18.2 hours.
Mars's axial tilt is 25.19 degrees, which is similar to
the axial tilt of the Earth.
Mars has seasons like the Earth, Mars they are
about twice as long given its longer year.
Orbit and rotation of Mars and surrounding planets.
The gravity on Mars is much lower than on
Earth, 62% lower.
Mars gravity is 38% of Earth’s.
A person weighing 100 kg here would be 38
kg there (measurement of mass not weight)
Mars is smaller than Earth in all the factors that
determine the gravity of a planet.
The affects of long term exposure to different strengths of gravity
is an area of study concerning human exploration of other planets.
It is known that humans can suffer bone loss and other health
problems, but exact studies need to be conducted to test the topend duration of a human mission.
MIT researchers have proposed one such study involving a group
The mice would be launched aboard a small satellite, which
would be spun so that the force mimics Mars’ gravity. In the
proposition 15 mice will orbit Earth for five weeks.
The mission is called the Mars Gravity Biosatellite Program.
The project could cost over $15 million plus the cost of the launch
and is still seeking funding. By 2009, the project had engaged over
600 undergraduate, graduate, and high school students in
aerospace engineering, space life sciences, and program
management, earning multiple student awards.
The mission is currently scheduled to launch in 2014 or 2016.
A vast meteorite impact basin located at 42°
42'S 70° 00'E_, in the Mars southern
hemisphere. Also known as the Hellas Impact
Basin, this landmark has a very obvious
impact crater ring 2,300 km in diameter. This is
one of the largest known impact craters in
the solar system.
Asaph Hall, an American astronomer, worked as a carpenter
and a school teacher but studied the stars and became a
celebrity scientist in his era. He had written several articles
published in scientific articles and after he found academic
positions at Harvard and US Naval Observatory. He had
traveled to Vladivostok, Russia in 1874 and San Antonio,
Texas in 1882 to observe two transits of Venus.
He has used what was then, back in 1877 on August 11th and
17, the world's largest refracting telescope and discovered the
two Martian moons Phobos and Deimos, each about 18 miles
in diameter. He received rewards from the Royal
Astronomical Society's Gold and Medal, and he was named
the Naval Observatory's Professor of Mathematics by
President Abraham Lincoln.
He has published
almost 500 papers.
His papers included
studies of double
stars, the mass of
rings solar and stellar
parallax, and the
value of pi.
The month of March is named after Mars.
The symbol for Mars looks like a shield and a
spear from the war god Mars/Ares. It is also the
symbol for the male sex.
Egyptians called Mars the “the backward traveler”
because Mars appeared to move backwards
through the zodiac every 25.7 months.
Mars’ red color is due to iron oxide, also known as
rust, and has the consistency of talcum powder.
Literally, the metallic rocks on Mars are rusting.
If you were driving 60 mph in a car, it would take
271 years and 221 days to get to Mars from Earth.
Mars contains the largest labyrinth of intersecting
canyons in the solar system called the
Mars has the largest and most violent dust storms in
our entire solar system. These storms often have winds
topping 125 mph, can last for weeks, and can cover the
entire planet. They usually occur when Mars is closest
to the sun.
In 1976, Viking I photographed a mesa on Mars that
had the appearance of a human face. Many individuals
and organizations interested in extraterrestrial life
argued that intelligent beings created the “Face.”
Though the Mars Global Surveyor revealed that the
“Face” was likely an optical illusion, believers in the
“Face” charged NASA with stripping data from the
new image before it was released to the public.
The “Face“ on Mars: 1976 Viking view (left); 2001 MGS
NASA/JPL-Caltech/University of Arizona/Texas A&M University