Mercury :: essays research papers

hydrargyrumMercury is the closest planet to the sun. Its average distance fromthe sun is approximately fifty-eight million km and its diameter is 4875 km,making it the second smallest planet in our solar system. Its volume and mass be about 1/18 that of the earth and its average density is approximately equalto that of the earth. Mercurys magnetic field is one-hundred times weaker thanthat of Earths. Mercury has the shortest revolution of all the planets in oursolar system and revolves around the sun in about eighty-eight days. Radarobservations of the planet show that its period of rotation is 58.7 days, ortwo-thirds of its period of revolution. That means that Mercury has one andone-half days in its year.Mercury doesnt micturate an atmosphere, but it does have a thin layer ofhelium. The helium is genuinely solar wind that is trapped by Mercurys weakgravity. Scientists think that collisions with protoplanets early in thehistory of the solar system may have stripped a carriage lig hter materials, makingMercury a very dense planet with an iron core extending outwards 4/5 of the wayto the surface.Mercury bares a very similar resemblance to our moon because it has alot of craters. The craters, which cover seventy-five percent of Mercuryssurface, were formed by huge rocks that smashed into the planets surface. Thelargest crater is called the Caloris Basin and it is 1400 km in diameter and isflooded with molten lava. Mercury also has many cliffs that are usually over300 miles long and two miles high. The rest of the planets surface is smoothand may have been formed by lava flowing out of cracks in the surface.Temperatures on Mercury vary greatly because of its closeness to thesun. The surface temperature on the sunlit side is about 430 degrees Celsius,while the smuggled side may reach temperatures of -170 degrees Celsius..Mercury was a difficult planet to study before the invention of thetelescope. Even then, you could only see Mercury in the morning and evening .Then the Mariner 10 was built in the 1970s to go observe Mercury.