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Planetary Walkway: Mars
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In memory of my sister, Gwen Butti Mackay
Andy Butti
The red planet Mars has inspired wild flights of imagination over the centuries, as well as intense scientific interest. Mars has some remarkable geological characteristics, including the largest volcanic mountain in the solar system, Olympus Mons.
Mars was named after the Roman god of war. The hostile "red" light reflected from its surface gives it an ominous bloody aspect like none of the other planets. Mars is about ½ the size of Earth and is approximately 1.5 times further from the Sun than is the Earth. Therefore Mars is 1.52 A.U. from the Sun and is considered the outer most terrestrial planet. Mars is the planet astrobiologists and astronomers would like to visit most in the Solar System. NASA is preparing several missions to the Moon in preparation to take a giant step to explore the surface of Mars. Astrobiologists believe there is the potential that life could have evolved on the red planet either sometime in the past or might still exist there. Mars has an average surface temperature of (-63° C or -81° F) with a maximum temperature of (20° C or 68° F) and a minimum temperature of (-140° C or -220°F). The surface atmospheric pressure averages over the year at approximately 7.0 millibars on Mars whereas the average atmospheric pressure of the Earth at sea level is 1000 millibars. This pressure is less that 1.0% that of the Earth and is a major reason why water can not exist in the liquid form on the surface of Mars, presently. The atmosphere of Mars is very thin and is comprised of approximately 96% carbon dioxide and less about 0.013% water vapor.
Mars has seasons because it has a tilted axis. The tilt of Mars is 23.98° as compared to Earth's axial tilt of 23.5°. A day on Mars known as a sol is 24.6 hours and a year on Mars is approximately 2 Earth years (686.9 Earth days). The month of March is named for Mars. Recently, NASA's Rovers have discovered a mineral (hematite) on Mars that indicates liquid water existed on the surface of Mars several billion years ago. Plans are being made by the University of Arizona, to launch the space probe Phoenix in early August of 2007 and land on the surface of Mars.
Quick Facts
- Mean Distance from Sun: 227,936,640 kilometers
- Orbital Period: 1.88 years
- Rotational Period: 24 hours 37 minutes
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| Mars as seen from the Hubble Space Telescope. | ||