Mission:
SPACE guests end their pulse-racing, deep-space adventure on a planet wrapped
in mystery and steeped in fable:
Earthlings have had an ageless fascination
with Mars -- one of the brightest objects in the night sky -- since its discovery
in prehistoric times.
Here are some facts -- and a few fantasies -- about
the "red planet" . . .
A visit to Mars is a great way
to lose weight fast -- without giving up any gastronomic delights. Unfortunately,
the weight loss is a mirage -- based solely on the gravitational pull at the surface
of Mars. It's only 38 percent the gravitational pull of Earth. Thus, a 250-pounder
on Earth steps off the spacecraft on Mars and is a 95-pounder.
Mars, the fourth planet from the
sun, is about one-and-a-half times as far from the sun as Earth. On average, Mars
is 142 million miles from the sun while Earth is 93 million miles away.
Mars' orbit brings it to within
approximately 35 million miles of Earth once about every two years. At its most
distant from Earth, Mars is 248 million miles away. Missions have typically been
undertaken in timeframes when the planets are "close" and have involved approximately
200 days of travel. Average speed for the journey: approximately 7,300 miles per
hour.
Mars is generally very cold. The
average temperature: -85° Fahrenheit (-65° C). If that's not "unreasonably cold"
enough, consider the extreme: -193° F (-125° C). A heat wave: a pleasant +77°
F (+25° C) during the Martian "summer" -- but probably only at your feet and near
the equator!
Mars' air in two words: Thin, unbreathable.
The average surface pressure is about six millibars. On a barometer, that would
be about 0.18 inches of mercury (on Earth, the weathercasters typically report
barometric readings around 30.00). As for the content of Mars' thin air: 95% carbon
dioxide, 3% nitrogen, 1.5% argon, trace amounts of water vapor and oxygen (Earth
has 78% nitrogen, 21% oxygen, 1% argon, and 0.03% carbon dioxide).
Huge surface features on Mars include
the tallest known volcano in the solar system (Olympus Mons is 13 miles high and
373 miles across -- an area about the size of Arizona) and the largest known canyon
system in the solar system (Valles Marineris is up to 6.8 miles deep and nearly
2,500 miles long). Olympus Mons is more than 2 1/5 times higher than Mount Everest.
The length of Valles Marineris is approximately the same as the driving distance
from California to Washington, D.C.
Mars is a smaller world than Earth
-- about 4,222 miles in diameter (Earth is 7,926 miles).
Man's fascination with Mars combined
with advances in science has led to more than 40 attempts to send unmanned (robotic)
spacecraft carrying various scientific equipment to the red planet. Here are several
milestones:
First attempted Mars mission: Marsnik 1 (U.S.S.R.);
ended with launch failure on Oct. 10, 1960.
First successful Mars
flyby mission: Mariner 4 (NASA); launched on Nov. 28, 1964, arrived at Mars for
flyby 228 days later (July 1965).
First partially successful Mars
orbiter mission: Mars 2 (U.S.S.R.); launched on May 19, 1971; began orbiting Mars
on Nov. 27, 1971; completed 362 orbits by August 1972 when the mission was deemed
completed (but no useful images of the surface were acquired).
First
successful scientific orbiting mission to Mars: Mariner 9 (NASA), which was launched
May 30, 1970, and ended its mission on Oct. 27, 1972.
First partially
successful Mars lander mission: Mars 3 (U.S.S.R.); launched on May 28, 1971; lander
achieved a soft landing on Dec. 2, 1971, and began operations; however, instruments
ceased working for unknown reasons after just 20 seconds, with no return of any
scientific data.
First successful biological exploration of another
planet: Viking 1 and 2 (NASA), launched August 1975, arrived at Mars in June and
July 1976, with landings July 20, 1976, and Sept. 3, 1976; performed first-ever
exploration of the biology of another world with 13 sophisticated experiments,
and operated for up to 6 years on the Martian surface together with two orbiters.
First successful Mars rover mission: Mars Pathfinder (NASA); launched
on Dec. 4, 1996; landing occurred on July 4, 1997, and the rover was deployed
on July 6, 1997; it explored the Martian landscape for nearly three months (83
days), together with a fixed lander, which relayed information to Earth.
First
global topographic mapping of another world: Mars Global Surveyor (NASA), launched
November 1996, arrived into orbit September 1997, and still operating in Mars
orbit today; this intrepid NASA mission acquired more than 600 million highly
precise laser-based measurements of the relief of the Martian surface and assembled
them into a relief map of Mars that has a higher accuracy than existing maps for
some continents on Earth (i.e., its accurate to about 1 foot everywhere). We know
where the water will "run" on Mars better than anywhere else in the solar system.
Athena Mars Exploration Rovers: Launched on June 10, 2003, aboard
a Delta II rocket, Spirit is a roving vehicle the size of a golf cart; it is moving
toward a planned Jan. 4, 2004, touchdown on Mars.
Mars is composed mostly of rock
(like Earth) with a core believed to be less iron-rich than Earth's. And it once
had a great big magnetic field like Earth so that compasses would have been invaluable
on those long, cold hikes, but alas it lost its field somehow a long time ago.
Some rocks are basalt (volcanic lava) while the composition of other rocks is
not well known (speculation regarding the reason for the rusty-red appearance
of the planet varies from the presence of an abundance of iron on the surface
to the presence of reddish dust such as the soil formed from volcanic rock). Many
rocks MAY have been formed like those in the walls of the Grand Canyon -- by the
action of ancient lakes, seas and rivers.
Mars is a water-bearing planet,
but we are not yet sure how much water it has and how often that water, presently
stored as ice and gas (in the atmosphere), exists in a liquid state.
Mars' presence in the sky was observed
in prehistoric times. The vivid red color of the planet often associated it with
war or death. It is named after the Roman god of war. Hindu mythology associates
it with Karttikeya, the war god. Babylonians called it Nergal (god of death and
pestilence).
Mars' day -- that is, the amount
of time it takes to complete one rotation around its axis -- is 24.6 Earth hours.
So a day on Mars -- called a sol -- is just a little longer than an Earth day
(23 hours and 56 minutes). A Mars year, however, is very long as the planet completes
a lengthy revolution around the sun: 687 Earth days or 1.88 Earth years.
Mars has two small moons: Phobos
(about 13 miles across) and Deimos (about 7½ miles across). Phobos means "fear";
Deimos, "panic."
Ever since H.G. Wells envisioned
a society of war mongers in "War of the Worlds," fascination with Mars has been
a popular topic for fiction writers . . . Several of the "classic" and modern
works of note: Ray Bradbury's "The Martian Chronicles," Edgar Rice Burroughs'
series of adventure books, and Kim Stanley Robinson's "Red Mars," "Green Mars,"
and "Blue Mars."
Orson Welles' 1938 radio dramatization
of H.G. Wells' "War of the Worlds" -- produced as a music show with very realistic-sounding
news breaks about Martians invading a small town in New Jersey -- is one of the
most memorable radio broadcasts of the 20th century.
More than 100 motion pictures filmed
between 1913 ("A Message from Mars") and 2003 ("The Hulk" and "Cowboy Bebop: The
Movie") have thrived on a fascination with Mars -- travel to the red planet and
contact with alien life: http://chapters.marssociety.org/sandiego/MarsMovies.html.
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