Why is mercury unusual

Watch it now, Wondrium. Once there, another extreme is that Mercury has incredibly long days. So a single year includes a lot more speed-up and slow-down during one orbit. This is not just an optical illusion. This elliptical orbit also gives Mercury seasons that are very different.

When Mercury is at perihelion, the Sun is twice as bright as when Mercury is at its furthest point, called aphelion. So there are seasons of the year that are hotter and seasons that are colder. Within our solar system, Mercury has by far the most elliptical orbit of the 8 planets. Learn more about orbiting Earth: up through the atmosphere. List of Partners vendors. Share Flipboard Email. Anne Marie Helmenstine, Ph. Chemistry Expert. Helmenstine holds a Ph.

She has taught science courses at the high school, college, and graduate levels. Facebook Facebook Twitter Twitter. Updated January 13, Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph. Why Is Mercury a Liquid? Even though Mercury is the closest planet to the sun, its surface can still be extremely cold.

The temperature during the day can reach degrees Fahrenheit degrees Celsius , but at night, temperatures can get as low as minus F minus C. That fluctuation equals a temperature swing of more than 1, F C , the largest of any planet in the solar system. Mercury is the smallest planet in the solar system. The diminutive planet is about 3, miles 4, kilometers in diameter, making it about the size of the continental United States and only slightly bigger than Earth's moon.

It's smaller than both Saturn's moon Titan and Jupiter's moon Ganymede. Pluto used to be considered the smallest planet in the solar system, but it was downgraded to a "dwarf planet," leaving the distinction to Mercury. Scientists think that a huge asteroid slammed into Mercury about 4 billion years ago, creating a giant crater about miles 1, km across. Mercury has a unique electronic configuration which strongly resists removal of an electron, making mercury behave similarly to noble gas elements.

The weak bonds formed by these elements become solids which melt easily at relatively low temperatures. Mercury does not react with most acids, although oxidizing acids such as concentrated sulfuric acid and nitric acid dissolve it to give sulfate, nitrate, and chloride salts.

Like silver, mercury reacts with atmospheric hydrogen sulfide. Mercury even reacts with solid sulfur flakes, which are used in mercury spill kits to absorb mercury vapors. Mercury dissolves to form amalgams with gold, zinc, and many other metals.

Iron is an exception, and iron flasks have been traditionally used to trade mercury. Sodium amalgam is a common reducing agent in organic synthesis, and it is also used in high-pressure sodium lamps.