Mars (What is it?)
Mars, the 4th planet from the sun and the closest planet to earth, is named after the Roman god of war, "Mars." Often reffered to as the "Red Planet", Mars gets its reddish colour from the iron oxide on its surface.


Physical Attributes
Mars - Earth Comparison
Mars is about 9 times smaller than Earth, and is roughly double the diameter of the Moon. Mars has an average surface temperature of -63°C.In the geological history of Mars, there are three periods that are the most significant:

Noachian period: This period included the formaton of the oldest extant surfaces of Mars (4.5 billion years ago to 3.5 billion years ago.) The surfaces of this age are subject to many large impact craters.

Hesperian period:3.5 billion years ago to 2.9-3.3 billion years ago. This period is distinguished by the formation of broad lava plains.

Amazonian period: 2.9-3.3 billion years ago to present. The regions in the Amazonian period have few meteorite impact craters. This period also included the formation of Olympus Mons.

Images were taken on February 19, 2008 of an avalanche from a 700 m high cliff, indicating that there is still geological activity taking place on Mars.

Mars' Moons - Deimos (Left) & Phobos (Right)

Mars has two moons, Phobos and Deimos, which are small and irregularly shaped. These may be captured asteroids which through time have formed into and are classified as moons, similar to 5261 Eureka which is a Martian Trojan asteroid. Phobos and Deimos appear very different from our own moon, when looked at from the surface of Mars. Phobos rises in the west and sets in the east, while Deimos rises in the east and sets in the west. Phobos rises again just 11 hours after it sets and Deimos has an orbit of 30 hours. Phobos is scheduled to either crash into the surface of Mars or break up and form a ring structure around the planet, in about 50 million years. This will be as a result of it being below synchronous altitude, and because the tidal forces of Mars are gradually lowering its orbit.

Martian Climate
Mars Forecast

The climate on Mars is dry, cold, and clear. In the summer daytime temperatures at the equator can be as warm as 20 C. Nice short sleeve weather and comfortable for most activity. But that same night, temperatures can drop to -90 C. The 110 degree difference in one day can create warm and cold temperature fronts that can lead to dust devils and dust storms that can engulf the entire planet for weeks. Winter temperatures can stay as low as -140 C. The carbon dioxide in the air freezes and becomes dry ice. The Martian North Pole has a one meter layer of dry ice in the winter, while the South Pole is covered by a permanent eight meter deep layer.

It never rains on Mars because of the thin atmosphere and the lack of a magnetosphere. Occasionally, however, clouds do form and snow does fall. Clouds on Mars are very small and wispy and the majority of them are formed by carbon dioxide ice. Scientists believe that a few are comprised of small water particles. Since Mars is so cold the water in these clouds could never fall as rain, but can fall as snow in the upper atmosphere of the planet. Scientists have only seen this a few times and have no evidence that the snow ever reaches the ground.

The most dramatic version of Mars weather is the dust storm. They occur frequently because of the temperature gradient on the planet and because the surface is covered in light dust that is easily picked up by wind.

Orbit & Rotation of Mars
Orbit of Mars compared to Earth

Mars is located 230 million kilometres from the sun, and takes 687 days (1 year and 320 days) to complete a full orbit of the sun. A day on Mars is longer than a day on Earth, but only by 39 minutes. Mars has an axial tilt of 25 degrees, similar to that of Earth. This means that Mars has seasons just like Earth, although its seasons are almost twice as long as our season, as a result of its longer years. Mars has an orbital eccentricity ( the amount by which an object's orbital path is different from a perfect circle) of about 0.09, the second greatest in the Solar System; only Mercury having areater eccentricity. For the last 35000 years Mars has been getting slightly more eccentric, meaning its path has become less of a perfect circle. This is as a result of the gravitational effects of other planets.

Panorama of Mars
Panorama of Mars

Future Exploration of Mars
New Mars Rover Curiosity

NASA's new Mars Rover, Curiosity, is a car-sized Mars Science Laboratory, which is scheduled to launch later this year. The future home for the Mars Rover Curiosity is located in a crater called Gale Crater, a crater spanning 154 km in diameter. Gale Crater contains a mountain rising high from the crater floor. Gale Crater is equivalent in size to the combined area of Connecticut and Rhode Island. The mission will last one Martian year (nearly two Earth years). During that time, researchers will make use of Curiosity's tools to study the landing region, and whether the environmental conditions are alright to support microbial life. Curiosity is scheduled to land in August of next year.