Mercury's atmosphere is primarily made up of oxygen, potassium, sodium, helium and hydrogen. The atmosphere on Mercury is made up of atoms that are launched from the planet's surface from micrometeoroid impacts and solar wind. The atmosphere or exosphere on Mercury is very thin, which means the planet receives large amounts of heat from the sun, making daytime hours very hot.
Because the atmosphere on Mercury is thin, it does not retain heat well, which results in temperatures dropping as low as -290 degrees Fahrenheit at night. Temperatures can reach as high as 800 degrees Fahrenheit during the day, making it impossible for any life to survive on the planet. Mercury orbits around the sun every 88 days and makes a complete rotation on its axis in a period of time that is equal to 59 Earth days.Learn More
Saturn's atmosphere is made up of about 75 percent hydrogen and 25 percent helium, along with trace amounts of water ice and other gases. Like the other planets in the outer solar system, Saturn is a gas giant that lacks a solid surface.Full Answer >
When Pluto has an atmosphere, it is thought to be made up of methane, nitrogen and carbon monoxide in gaseous form. This atmosphere outgases from the ice on Pluto's surface when it is closest to the sun, which warms the planet and causes the ice to sublimate.Full Answer >
Mars' atmosphere is made mostly of carbon dioxide, with some nitrogen and argon. It has a very small amount of oxygen and carbon monoxide and tiny amounts of noble gases and other compounds. Earth's atmosphere is 100 times thicker than the atmosphere of Mars.Full Answer >
Mercury has a radius of 2,439.7 kilometers, making it smaller than some moons and the smallest planet in the solar system. Its mass is equal to 0.055 of Earth's.Full Answer >