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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33 Comments
imflamey3 monthsOr it was a rock plant and then the ice melted and it’s rock now and it all water
ilovehenrydsaf3 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?
teddybearlife3 monthsI agree- imflamey3 monthsYeah that’s right thanks for the advise:p
peacey_bon-bon3 monthscool!
s0ccerbeast20133 monthsI feel like they are made from rock and ice. So 1 that can be very dangerous 😱
sophia03133 monthsWe never been to Uranus and Neptune,so it's obvious researchers wonder about it.
lukogizasope3 monthsVORYGER 2
anne03273 monthsWOW soooo cool
chocolaterose753 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.
qwertyasd3333 monthswow
ramona123453 monthsI had to do this for my homework
dusesuvufapo3 monthsmabyye they have emense heat in some areas
jupiter_stormy3 monthsyeah they would be cold but they could also be made of rock and ice too
