In 1952, science fiction writer James Blish coined the term gas giant and it was used to refer to the large non- terrestrial planets of the Solar System. Uranus and Neptune consist of only about 20% hydrogen and helium by mass, compared to the Solar System's gas giants, Jupiter and Saturn, which are more than 90% hydrogen and helium by mass. ![]() Instead, water primarily exists as supercritical fluid at the temperatures and pressures within them. Today, very little of the water in Uranus and Neptune remains in the form of ice. Their constituent compounds were solids when they were primarily incorporated into the planets during their formation, either directly in the form of ice or trapped in water ice. Lacking well-defined solid surfaces, they are primarily composed of gases and liquids. Īs such, Neptune and Uranus are now referred to as ice giants. In the 1990s, it was determined that Uranus and Neptune were a distinct class of giant planet, separate from the other giant planets, Jupiter and Saturn, which are gas giants predominantly composed of hydrogen and helium. In astrophysics and planetary science the term "ice" refers to volatile chemical compounds with freezing points above about 100 K, such as water, ammonia, or methane, with freezing points of 273 K (0☌), 195 K (−78☌), and 91 K (−182☌), respectively (see Volatiles). ![]() ![]() There are two ice giants in the Solar System: Uranus and Neptune. Neptune photographed by Voyager 2 in August 1989Īn ice giant is a giant planet composed mainly of elements heavier than hydrogen and helium, such as oxygen, carbon, nitrogen, and sulfur.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |