Mercury is the innermost planet our Solar System and although no exact date is known of its discovery one of the earliest records comes from the Sumerian civilisation around 3,000 BC. Due to the speed in which it moved around the Sun Mercury was named after the Roman god Mercury, who according to myth was the god of travellers and messengers, had a winged hat and sandals, so he could fly. A day on Mercury lasts for 4222 and a half earth hours, which is the equivalent of 58.6 Earth days or your average Monday in work. A Mercurian year will take 88 Earth days on its speedy journey around the Sun reaching speeds of 200,000 kilometres an hour in the most elliptical of all the 8 planets, sorta looks like a big egg! Mercury is a very dense planet one of the densest planets of our solar system, second only to earth! It’s made up of lots and lots of metals, mostly iron, with a thin crust of rock that is heavily cratered. In Fact Mercury is the most cratered planet on the entire solar system with a surface not dissimilar to that of Earth’s moon and the continued presence of these craters indicates that the planet has not been geologically active for billions of years.
Mercury being the smallest of the planets in our solar system with a diameter of only 4,879 km or 3031ish Miles means that it is only slightly larger than Earth’s moon! Its small stature causes the gravity on Mercury to be only 38% of that on Earth meaning that I would only weigh about 4 and a half stone or 28.6 Kg if I were to stand on its surface. Temperatures vary between a scorching 800 degrees Fahrenheit (430 degrees Celsius) during the day to a chilly -280 degrees Fahrenheit (-170 degrees Celsius) at night. It is possible to see Mercury from the Earth with the naked eye though its closeness to the Sun’s bright light can make it difficult to spot. Astronomers used to believe that Mercury was tidally locked with the sun with one side always facing the sun. However in 1965 astronomers discovered that the planet rotates three times during every two orbits. Due to its close proximity to the Sun only two spacecraft have ever visited Mercury to date, Mariner 10 and Messenger. During 1974 and 1975, Mariner 10 flew by Mercury three times mapping around half of the planet’s surface, discovered its thin atmosphere and detected its weak magnetic field. Messenger went into orbit around Mercury in 2011, and completed mapping of 100% of Mercury’s surface in 2013. A mission to Mercury is “BepiColombo” is planned for launch 27 January 2017 and hopes to enter orbit around Mercury in 2024, I’ll be 42! The two orbiters will explore Mercury for one Earth year (4 Mercury years), with the option of a one-year extension. One of the many things these orbiters will be looking for is evidence of liquid water. Scientists and astronomer’s believe there could be liquid water located in the shadows of huge craters at the poles due to Mercury’s axial tilt is of 2.11. To give you some perspective the Earths axial tilt is 23.4 which gives us our seasons as we travel around our orbit.
I always imagined Mercury as a tortured burnt ball of Rock and Iron but in my research I have discovered it is, well it is a tortured burnt ball of Rock and Iron but with many other fascinating aspects. I have touched on the things that I found interesting and could explain while trying to keeping it interesting and in laymen’s terms. Below are the links to all of the sites which I used to research Mercury. I would advise you to check out www.astronomycast.com and www.universetoday.com.