Are Uranus And Neptune Really Ice Giants?
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Uranus and Neptune are often called "ice giants." This is based on the theory that they were made from materials that easily freeze in space, like water and ammonia. However, this label does not come from direct observations, since no spacecraft has visited the two giants since Voyager 2 in the 1980s. Instead, it is drawn from computer models built using the planets’ sizes, masses, densities, and gravity fields. Now, a new study by scientists at the University of Zurich is challenging this idea. It suggests that the two planets may contain more rock than ice.
The researchers began by creating hundreds of computer models to see what might be inside each planet. Instead of assuming they were mostly ice, they tried different amounts of rock, water, and other materials. They then compared the results with known facts, like each planet’s mass and gravity. This showed them which combinations of materials could really exist inside the planets.
For Uranus, the models showed many possibilities. They ranged from being almost all water to having nearly four times as much rock as water. Neptune showed a similarly broad spread. Its rock-to-water ratios varied from mostly water to nearly twice as much rock as water.
The scientists shared their results in the journal Astronomy and Astrophysics on September 30, 2025. They assert that if these planets have as much rock as some models suggest, calling them "ice giants" might be incorrect. However, the only way to know for sure is to send a spacecraft to study these distant worlds up close. Unfortunately, with no such missions planned, the true makeup of Uranus and Neptune remains a mystery.
Resources: Space.com, CNN.com, Smithsonianmag.com
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39 Comments
vinrongabout 1 monthA long time ago, a asteroid hit the Earth into shatter pieces and formed into the moon.
teddybearlifeabout 1 monthI like the article- mewybybylomeabout 2 monthsJames says: "I wondered if they could send another telescope so they could get some pictures of both planets and send out tiny probes to get more samples?" Grandma says: "It is interesting how "facts" change as science gains more information through research and study."
ilovehenrydsafabout 2 monthsErr... Huh?
i_love_godabout 2 monthsI think they are the Ice giants because they are the farthest plants away from the sun! :)- lisekytebysaabout 1 monthbut what if there is more rock then ice
- vinrongabout 1 monthPluto is the smallest,farthest,and a dwarf plants away from the sun
imflameyabout 2 monthsOr it was a rock plant and then the ice melted and it’s rock now and it all water- ilovehenrydsafabout 2 monthsI doubt it. How would it melt if its so far away from the sun? If winter on earth freezes water due to the sun shining ever so slightly less, how would the ice melt that far away?
- teddybearlifeabout 1 monthI agree
- imflameyabout 2 monthsYeah that’s right thanks for the advise:p
tony67about 2 monthsThat is smart
peacey_bon-bonabout 2 monthscool!
s0ccerbeast2013about 2 monthsI feel like they are made from rock and ice. So 1 that can be very dangerous 😱
sophia0313about 2 monthsWe never been to Uranus and Neptune,so it's obvious researchers wonder about it.
lukogizasopeabout 1 monthVORYGER 2
anne0327about 2 monthsWOW soooo cool
chocolaterose75about 2 monthsWhat if they aren't really ice giants? If they are not, schools really messed up the teachings of the solar system for my generation.