Mars has a very thin atmosphere, approximately 100 times thinner than earth’s. It is primarily made up of Carbon Dioxide, Nitrogen, Argon, Carbon Monoxide, and Oxygen. The atmosphere is just thick enough to support clouds and wind. Weather does occur within the atmosphere of mars, two examples are sandstorms and Carbon Dioxide based snow.
This image shows some of the craters that are on mars. Present craters were caused by meteors crashing into the surface.
This picture shows the light areas and dark areas on mars. The light areas have a reddish-brown color are cover about two-thirds of the surface. Just like our deserts, Mars is covered in dust, sand, and rocks.
This is an image of the very beginning of what could be a massive sand storm on mars. Uneven heating on the surface of the planet is the cause of very strong and powerful winds. These winds kick up sand and dust that sits on top of the surface.
This is a volcano called Olympus Mons, which is located on the surface of mars. There are many very large volcanoes such as this one on mars because it has been billions of years since any tectonic plate action has occurred. Scientist have discovered that this is the largest volcano in our solar system.
There are many reasons why Mars is one of the best candidates for supporting life. Organizations such as NASA have sent rovers up into space, to land on mars and investigate. These machines take many pictures and collect lots of data. Scientists have discovered that there is a small percentage of oxygen within the atmosphere of Mars, this says that life could possibly be supported on mars. Also, there is evidence that water once existed on this planet. We can clearly see that there are dried up stream beds located in various locations. In 1996 scientists discovered a meteorite located on Antarctica thats is thought to have been part of mars. They say that this meteorite contains traces of Martian atmosphere. Scientists then found what they thought was fossilized bacteria, suggesting that there was once life on Mars. This things, along with many other pieces of evidence make Mars one of the best candidates for supporting life.
There are two Martian Polar Ice caps located one Mars. One is located around the north pole, and the other in the south. Both caps are primarily made up of water ice. During the poles winter, when it is completely dark, around 30% of the atmosphere is deposited into the ice. This means that the CO2 gas in the atmosphere is condensed into a liquid, which then forms dry ice. In the summer, when the poles are again exposed to sunlight, the frozen CO2 changes back into a gas. This process creates massive winds that sweep off the poles at around 400 km/h. Mars has seasons similar to winter, because the degree it is tilted is close to the degree earth is tilted. During the northern winter, a thin layer of frozen CO2 accumulates on the north cap. Whereas the south cap is a permanent layer of dry ice that is about 8 meters thick.
The Northern Ice Cap of mars.
The Southern Polar Cap
All sand and dust storms on Mars are generated by sunlight. When the sun heats up parts of the atmosphere on mars which causes the air to begin to move. This picks up dust from the surface of Mars. Seeing as the atmosphere on Mars is about 1% as dense as the atmosphere on earth. As a result, small grains of dust can stay suspended in the air. This creates a large cloud, and as the cloud travels it picks up more and more dust. Eventually the entire planet can be covered by dust and sand. Most sand and dust storms originate in Hellas Basin, the deepest crater in our solar system. The temperature of the surface within the Basin can be up to 10 degrees hotter than the rest of the planet. This uneven heating creates wind action that picks up dust and sand. This is why many storms emerge from the Hellas Basin.
In this image we can see Mars in june of 2001. By July the color and appearance of the planet had completely changed. This is because a massive cloud of dust and sand was coating the planet. This is a common result of a sand and dust storm.
Many rovers have been sent up into space to land and investigate many different places and planets, Mars is a very common location. The main purpose of sending rovers to Mars are to determine if life ever existed or dow exist on mars, to characterize the climate and geology of mars, and to prepare for human exploration. A rover is a automated motor vehicle, that has the ability to gather information about a certain area and send it back down to earth. There have been a total of four successful robotically operated rovers sent to Mars: Curiosity, Opportunity, Spirit and Sojourner. These four rovers are shown in the pictures below.
Mars has two small moons named Phobos and Deimos, which were discovered in 1877 by Asaph Halph. Phobos has the meaning of fear, and Deimos means panic. Scientists believe that these two moons did not form with the planet, but were captured asteroids. This is a reasonable theory because Mars is located nearby the asteroid belt. Both moons are fairly small, approximately one-third the size of our moon. The smaller moon, Deimos has a diameter of 8 kilometers. It is suspended about 23,460 km above the surface of mars and has an orbital period of 1.263 days. The other moon, Phobos is slightly larger than Deimos with the dimensions of 28 by 20 km. It is much closer to mars, at 9,270 km above the surface. It also has an orbital period of .319 days.
This image shows the two moons on mars and their orbital path. It also illustrates their size in comparison to the planet of mars.
A new rover recently took pictures of rocky outcroppings that stick out in the soil on Mars. The rock layers is about four inches thick, and is made up of gravel material in a sandy matrix. Some of the rock has been eroded away, and piles of small pebbles have been found in various locations. The pebbles within the rock are said to be smooth and round, this is a common feature of rocks that have been tossed around in rapidly moving water. There are also canyons and plains that have been carved out on the surface of Mars. This tells astronomers that at one point, there were running streams on Mars. NASA sent a rover up to mars in search of evidence that water once flowed on mars. They had this rover land on a crater called Gale. They selected this specific location because pictures from orbit showed what appeared to be an alluvial fan. Other pictures show a channel leading into the fan. Evidence of large amounts of water like this, increases the chances that there was once life on mars.
On the right is a picture of rock on earth that has been affected by streams. On the left is an image of a piece of rock on mars. As we can see, the two pictures look quite similar based on the size of pebbles within the rock and the erosion that occurred.
This is a wider image of what scientists believe is a former streambed on Mars.
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