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THE RED PLANET has long been the object of intense mystery. Mars captivated our imaginations as astronomers turned their telescopes toward the planet and envisioned a world not unlike our own. But was it inhabited by aliens poised to invade Earth?
Those blurry visions were cleared up when the first spacecraft sent to the planet in the 1960s revealed no signs of Martians, liquid water or vegetation. Although disappointing, those findings have not kept us from digging into Mars' past and the secrets it may hold.
Mars is a strange kind of place. It possesses the largest volcanic mountain in the solar system, Olympus Mons, and a canyon system named Mariner Valley that dwarfs Earth's Grand Canyon.
If Mariner Valley were on Earth, it would extend almost from one coast of the United States to the other. That's hard to imagine since Mars is about half the size of our own Earth.
Successful landings on Mars have been difficult to achieve, but there have been successes with the Viking 1 and 2 spacecraft in 1976, the Mars Pathfinder in 1997, and the twin Mars Exploration Rovers named Spirit and Opportunity in 2004.
Spirit and Opportunity continue to operate and roam the Red Planet almost four years later and have found evidence that Mars once had a great deal of water flowing on its surface.
What happened to the water is a mystery, but the prospect of ancient Martian life comes to mind. That's where the Phoenix Mars Mission comes in. The northern polar region of Mars will become the subject of intense study by this unmanned robotic spacecraft when it lands on Mars in May 2008.
Phoenix will dig into the Martian soil and analyze its chemistry to determine if life could have ever existed in Mars' past. Phoenix also comes equipped with an onboard weather station to measure the Martian weather.
Regardless of what Phoenix uncovers on Mars, NASA is planning future missions that are even more ambitious. One of these missions could bring samples of Martian rocks and soil to Earth for detailed physical and chemical analysis.
Though we cannot bring any pristine samples back from Mars at this point, rocks from Mars have landed on Earth in the form of meteorites. A few of these Martian meteorites have been the subject of great scientific debate, offering hints of possible microbial activity in the past.
More intriguing findings have also been uncovered by the Mars Global Surveyor spacecraft, which took pictures of gullies that may have been formed by running water.
In addition, the spacecraft took photos of an area on Mars indicating that something, possibly liquid, had flowed over the surface within the past few years. Perhaps Mars is not a dead planet after all.
For now, we can look at Mars and wonder about its past as it makes its best showing in the sky this month.
From the Fredericksburg area, it will rise in the east at sunset and will climb very high in the sky throughout the night, setting in the west as the sun rises. Its closest approach to the Earth actually occurs on Dec. 18, but it will be bright all month and into early next year.
As you gaze at Mars this month, think about its possibilities as the Phoenix spacecraft heads for a May encounter with the planet. Perhaps Mars will someday serve as an outpost for future generations of humans in a solar system of not one, but two planets teeming with life.
December Skies
This is the best month for observing Mars. It is conveniently located in the evening sky during prime-time hours, so go outside about two hours after sunset to see it rising in the east northeastern sky. If you need to use the moon as a guide to find Mars, they will be paired together on the evening of Dec. 23 and will be fairly close again before sunrise on the 24th.
Venus continues to greet early morning risers as it gleams in the southeastern sky before sunrise. It is the brightest object in the sky after the sun and moon, so you will not have any trouble locating it.
Saturn rises very late at night this month. On Dec. 28-29, the moon will pass below and to the left of Saturn in the early morning sky.
The Geminid meteor shower will dazzle Fredericksburg area residents during the evening of Dec. 14. Go outdoors after 10 p.m. and find the planet Mars climbing high in the sky. The constellation in which Mars is positioned this month is called Gemini. This is the general area where meteors will seem to radiate all night.
It is possible that up to 50 meteors per hour could be seen from a dark sky site. If the weather does not cooperate, you can still see meteors the night before and after the peak date of Dec. 14, but the hourly rates will be lower.
The winter solstice occurs on Dec. 22. This marks the beginning of winter for us in the Northern hemisphere. The days are short and the nights are long, making for great stargazing conditions, so get outside and enjoy astronomy!
David Abbou is a resident of Stafford County. He has been an amateur astronomer for more than 30 years and is a member of the Rappahannock Astronomy Club. Send questions or suggestions for future columns to david.abbou@verizon .net