The exploration of space has been one of the greatest achievements of the last century. The mission to the moon was of huge propaganda value to the United States at the height of the Cold War and it has been the aim to reach out to the planets and the stars for NASA ever since.
Mars has been frustrating, with numerous probes being unsuccessful, including the failed British Beagle 2 mission which crash landed in December 2003, although the European Space Agency's Mars Express Orbiter gained some good results and is still collecting images and data. NASA has the rovers Spirit and Opportunity currently on the planet. They have analysed rock samples, which suggest the previous presence of water and volcanic activity, but as yet, little sign of life.
Mars
Mars, named after the Roman God of War, is something of a conundrum. There are some vague similarities with Earth. The Martian day is only 40 minutes longer than an Earth day. [1] The planets' axial tilt is also similar to that of Earth, so it has seasons, like our planet does. The sky on Mars is a pink colour, due to the dust in the atmosphere. The surface is red in colour due to the presence of iron oxide, commonly known as rust. Mars is just too far out to have a warm enough temperature to support life, with daytime temperatures never reaching above freezing.
The Surface of Mars
There are two prominent polar ice caps which shrink and expand with the seasons visible using telescopes on Earth. It is possible to pick out these details with relatively small telescopes or binoculars. Keen observers can notice the ice caps with the naked eye when Mars is at its brightest, or when the planet is at its closest to Earth.
The observer may also notice periodic dust storms, a regular feature of Martian weather. The planet has extinct volcanoes, including the largest volcano in the Solar System, Olympus Mons, which was detected by the space probe Mariner 9 in 1971. This volcano is 400 miles wide and 15 miles high [2] There are numerous craters, similar to those found on the Moon. It is thought that the failed Beagle 2 probe landed in one of these craters, unable to climb out, and that is why there was no signal back to Earth.
Moons of Mars
Mars has two moons, Phobos (fear) and Deimos (panic), both discovered in 1877 by the American astronomer Asaph Hall. [3] These moons are not a regular shape. They are essentially two captured asteroids, held in Mars' gravitational field. Phobos orbits closer to Mars than Deimos. Phobos has large impact craters, which nearly tore the satellite apart early in its history. Phobos races around Mars in only 0.32 Martian days, whereas the further out satellite Deimos takes 1.26 Martian days to orbit Mars. [4]
Life On Mars?
Evidence supporting Mars once having life is sketchy, although NASA's Spirit and Opportunity rovers are finding more clues all the time. In the late 19th Century, astronomers noticed what appeared to be lines or channels across the surface suggesting rivers had once been flowing on the planet. However, later discoveries showed that any water would have evaporated and condensed with the carbon dioxide in the atmosphere to form dry ice, making the conditions too harsh for life. The latest news from the Mars Express Orbiter appears to support the theory that water once flowed on Mars, with dark areas of sediment observed in some of the dry craters and basins on the surface. [5]
In the future, it could well be possible to terraform the planet, by raising the temperature. There is a supply of water, with the ice in the polar caps, and with the emergence of bacteria, the atmosphere could be managed in such a way that oxygen could be produced from photosynthesis. One of the many stumbling blocks would be the atmosphere. It is very thin, which means that there is little protection from the harmful rays of the Sun. With the current state of technology, we will not be able to make the dream of colonising Mars a reality for decades yet. Mars will keep some secrets hidden for many years to come.
Sources
- Ian Ridpath, Book of the Universe, (Surrey, Dragon's World, 1991), 70
- ibid, 74
- NASA "Martian Moons." Mars Exploration Program, mars.jpl.nasa.gov
- ibid
- ESA " Wind and Water Have Shaped Schiaparelli on Mars." Mars Express esa.int
Claire Gorman - I am Claire Gorman, I live in Bradford, West Yorkshire. I have always wanted to write and my favourite author is Terry Pratchett. I am ...
