What is Mercury ?

Several forms of mercury occur naturally in the environment. The most common natural forms of mercury found in the environment are metallic mercury, mercuric sulphide, mercuric chloride, and methylmercury. Some micro-organisms and natural processes can change the mercury in the environment from one form to another.

Mercury is hard to study because it is so close to the sun.

People have never gone to Mercury. Spacecraft without people have gone. Mariner 10 was the first to visit Mercury. It flew by in 1974 and 1975. Not even half of Mercury was seen then. After that, nothing was sent to Mercury for more than 30 years...

Being an element, mercury cannot be broken down or degraded into harmless substances. Mercury may change between different states and species in its cycle, but its simplest form is elemental mercury, which itself is harmful to humans and the environment.

NASA's MESSENGER spacecraft flew by Mercury in 2008 and 2009. In March 2011, it began to orbit Mercury.

MESSENGER will study parts of Mercury that have not been seen before. It will let scientists learn many new things about the planet.

Mercury is tidally locked with the Sun in a 3:2 spin-orbit resonance,[15] and rotates in a way that is unique in the Solar System

Mercury's axis has the smallest tilt of any of the Solar

Two spacecraft have visited Mercury: Mariner 10 flew by in 1974 and 1975; and MESSENGER, launched in 2004, orbited Mercury over 4,000 times in four years before exhausting its fuel and crashing into the planet's surface on April 30, 2015....

Mercury appears to have a solid silicate crust and mantle overlying a solid, iron sulfide outer core layer, a deeper liquid core layer, and possibly a solid inner core.....

Mercury is one of four terrestrial planets in the Solar System, and is a rocky body like Earth.....

Mercury is much smaller and its inner regions are not as compressed. Therefore, for it to have such a high density, its core must be large and rich in iron....

Mercury's core has a higher iron content than that of any other major planet in the Solar System....

Mercury's surface is similar in appearance to that of the Moon, showing extensive mare-like plains and heavy cratering, indicating that it has been geologically inactive for billions of years....

Mercury is the closest planet to the Sun and due to its proximity it is not easily seen except during twilight....

Mercury completes three rotations about its axis and up until 1965 it was thought that the same side of Mercury constantly faced the Sun. Thirteen times a century Mercury can be observed from the Earth passing across the face of the Sun in an event called a transit, the next will occur on the 9th May 2016.....

One solar day (the time from noon to noon on the planet’s surface) on Mercury lasts the equivalent of 176 Earth days while the sidereal day (the time for 1 rotation in relation to a fixed point) lasts 59 Earth days.,....

One solar day (the time from noon to noon on the planet’s surface) on Mercury lasts the equivalent of 176 Earth days while the sidereal day (the time for 1 rotation in relation to a fixed point) lasts 59 Earth days.,....

Mercury is nearly tidally locked to the Sun and over time this has slowed the rotation of the planet to almost match its orbit around the Sun. Mercury also has the highest orbital eccentricity of all the planets with its distance from the Sun ranging from 46 to 70 million km.....

One of five planets visible with the naked eye a, Mercury is just 4,879 Kilometres across its equator, compared with 12,742 Kilometres for the Earth....

Mercury is very dense. Each cubic centimetre has a density of 5.4 grams, with only the Earth having a higher density. This is largely due to Mercury being composed mainly of heavy metals and rock.

The surface of Mercury which faces the Sun sees temperatures of up to 427°C, whilst on the alternate side this can be as low as -173°C. This is due to the planet having no atmosphere to help regulate the temperature.

Mercury is a difficult planet to visit. During 1974 and 1975 Mariner 10 flew by Mercury three times, during this time they mapped just under half of the planet’s surface.

Mercury’s discovery is unknown as it pre-dates its first historical mention, one of the first mentions being by the Sumerians around in 3,000 BC.

Mercury has just 38% the gravity of Earth, this is too little to hold on to what atmosphere it has which is blown away by solar winds