The Idiot’s Guide to Everything: Mars

Posted on November 8, 2011

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MARS

Out of all the planets in the solar system, Mars has the most storied history of any after Earth. Nicknamed the ‘Red planet’, it has fascinated mankind for century after century and appeared in popular fiction for most of that time. The question of whether there was, is or could be life on Mars is one that still tests scientists to this day, and the concept of intelligent Martian life is a favourite of any space geek. Simply put, it is one of the most fascinating worlds in all of our solar system

The fourth planet from the sun, Mars is about half the radius of Earth. In fact, the surface area of Mars is roughly the same as that of the land surface area on Earth. Its surface is composed mostly of basalt, and its reddy-orange appearance is due to the high level of iron oxide there, or rust as it’s more commonly known. Compared to the other terrestrial planets, Mars has a relatively low density, lower even than that of Mercury. It also has an equally thin atmosphere.

Again, as with the other planets in this half of our solar system, the surface of Mars is covered in craters. These craters however are only visible from the ground, and aren’t picked up by the Hubble telescope. Mars has similar land features to Earth, with volcanoes and hills covering the terrain. The largest of these, Olympus Mons, is the largest known peak in the solar system, rising up above the surface of Mars over 78,000 feet. It is twice the height of Mount Everest. It is located just off a region known as the Tharsis Bulge, which is home to three more humongous volcanoes. Nearby to this is also Valles Marineris, a huge valley that scientist Neil DeGrasse Tyron described as ‘the Grand Canyon, but on steroids and about the size of the US’. Very big indeed.

Temperatures on Mars rarely rise above freezing, with lows of -133 degrees Celsius. Similar to Earth, Mars has a rotational period of 24 hours (a day on Mars is only 39 minutes longer than a day on Earth), but its orbital period of almost twice that of Earth, at 687 earth days. It has a similar seasonal pattern to earth, all be it with much longer seasons due to the longer orbital period. The winters on Mars bring freezing, whereas the summers bring relatively high temperatures and incredibly fast wind speeds, which lead to storms that cover the planet in dust. It has a similarly eccentric elliptical orbit to Mercury, all be it not quite as eccentric, and sits an average of 230 million KM from the sun.

Mars has two small potato shaped moons, called Phobos and Deimos. These are extremely small, with Phobos at 27km long and Deimos at 15km long. These are known as minor satellites, resembling asteroids more than moons. Whilst the origins of Phobos and Deimos are uncertain, most theories centre on them being asteroids that were pulled into orbit around Mars.

As mentioned at the beginning, our fascination of Mars goes back centuries. Mars is named after the Roman god of War, because of its violent red appearance, and has been observed as far back as ancient Egypt. As is a recurring theme throughout these essays, the first telescopic observation of Mars was made by Galileo in 1610. Detailed maps of the planet began to be made around 1877, the first being put together by Schiaparelli. Schiaparelli identified channels on Mars’ surface, which when translated from the Italian into English were miss-translated as canals. This led to the first speculation that liquid water may exist or have existed on Mars, and of course this led to ideas of life on the red planet.

This hope fuelled research into Mars, and the 1960s saw the beginning of robotic spacecraft being sent out the red planet. Mariner 4 was the first successful fly by in 1964, and in 1971 Mariner 9 became the first spacecraft to enter a planets orbit. This led to a detailed mapping of Mars, and the discovery of many geological features, such as the Tharsis Bulge. This was followed by the Viking rovers in the 1970s, which landed on the planet and were able to send back fantastic photos.  When these missions mostly reported that the planet was a dry, cold, dead place, interest in Mars began to wane. Things were not helped by the fact that two thirds of all planned missions to Mars have ended in failure. Interest has picked up recently however, with the Russian and European space program recently completed a mock manned mission to Mars, with a number of cosmonauts holed up in a space together for the amount of time it would take to go to Mars and back, this being 520 days. Interestingly enough, these men were paid 1/10th of what Lindsay Lohan will be paid to pose in Playboy.

Mars has also been an integral part of science fiction for a very long time. Whether this is centred around the speculation that it could support life, the possibility of humans colonizing it in the future of just good old fashioned Martians getting up to no good away from their home planet, Mars has been a great source of inspiration for writers over the years. ‘Marvin the Martian’ was one of Disney’s Looney Tunes most prominent characters, Arnold Schwarzenegger’s character in ‘Total Recall’ had to journey to the red planet to uncover his past, the early computer game ‘Doom’ involves missions on the planet, and there are a huge number of novels based on Mars. This is just the tip of the iceberg.

When speaking about Mars, there really is only one question that comes to mind. Is there life on Mars? Has there ever been life on Mars? Will there ever be life on Mars? Okay, this is three questions, but the subject remains the same. An incredible amount of research has been put into the search for life, be it past, present or future, on the red planet. There are many stumbling blocks however. Mars has an extremely thin atmosphere, and it has no magnetic field. This means that is has no protection from the attack of heavy solar wind. There is little to no heat transfer across the planet. It is a geologically dead world, and has been for some time.

This has not stopped the speculation and hope however. It is thought that Mars used to have large oceans, much like those found on our own planet Earth. It is also believed to have been much warmer in times past, back when it had a magnetic field. The definitive answer to these questions could very well lie at the poles of Mars, in the polar ice caps. Here, much like Mercury, water is found in ice form, and if there is or ever was life on Mars, it’ll be found here. It is one of the biggest questions in all of science, and one that will baffle for many years to come.

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