Dwarf planet Eris – heavyweight turns out to be weak – Knowledge

The dwarf planet Eris once caused Pluto to be stripped of its status as a planet. Now there are amazing results.

It’s no coincidence that the dwarf planet Eris is named after the Greek goddess of discord: which is why Pluto was stripped of its planetary status about 20 years ago. At that time, Eris was discovered, a distant celestial body much heavier than Pluto and – as was thought at the time – much larger as well. Therefore, the International Astronomical Union announced the new category of dwarf planets, to which Pluto has since been included.

However, Pluto’s opponent soon turned out to be smaller than expected. And now a new one appears Stady: The previous rift mushroom is not as hard as it seemed: Iris’s surface is smooth. Soft ice cream. Modeling using data from Chile’s Giant ALMA telescope suggests: “You can imagine this ice cream as brie,” says Francis Nimmo of the University of California, Santa Cruz.

And what the researcher also discovered: Just like good soft cheese, Eris’s ice tends to flow slightly: “Streams of ice constantly rise from the warm, stony core of the dwarf planet to the surface. There they release heat into space, and when they cool, they sink back into the depths.”

So far, only Pluto, the only one of these ice dwarfs, is known among the dwarf planets in the Kuiper Belt. Space probe Checked on site. Pluto is almost the perfect twin of Eris, about the same size, with a warm, rocky core completely covered in ice. But according to the latest findings, the two are particularly different when it comes to ice: While it flows softly over Eris, Pluto is solid and mountainous. Beneath Pluto’s ice cap, experts suspect there is an ocean as thick as mud. For Iris, the ocean is less likely, but also conceivable.

Crazy idea: liquid water at unimaginably low temperatures on the outskirts of our solar system! However, this is an indication that, in addition to asteroids and comets, dwarf planets also brought water to Earth during previous collisions. Overall, these planets are exciting. “It is striking that almost all of them have their own small moons. This suggests that they, like our eight planets, formed at the beginning of the solar system, because there were still many collisions at that time in which the moons also exploded,” says Francis Nimmo. .

One would like to know more about distant dwarf planets – about Haumea, which has two moons and a ring, about Makemake with its methane ice, and about more than a hundred such objects that have yet to be discovered. However, a space mission to the Kuiper Belt is not on the horizon. So there’s little left to do but explore the distant ice dwarfs little by little with powerful telescopes and a lot of computing.