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by prox
974 days ago
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Now this is hackernews. Imagining working on spacecraft where no human made thing has gone before. Also is this correct? >NASA extended the mission so that Voyager 2 could visit Uranus and Neptune; it is still the only spacecraft ever to have encountered the >ice giants<. Aren’t they gas giants? I mean they are probably very cold, but usually they are called gas giants. |
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"Ice giant" seems to be the more modern terminology:
An ice giant is a giant planet composed mainly of elements heavier than hydrogen and helium, such as oxygen, carbon, nitrogen, and sulfur. There are two ice giants in the Solar System: Uranus and Neptune.
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°C), 195 K (−78°C), and 91 K (−182°C), respectively (see Volatiles). 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.
As such, Neptune and Uranus are now referred to as ice giants.
https://en.wikipedia.org/wiki/Ice_giant