Feb 21, 2026 01:57 AM
https://www.eurekalert.org/news-releases/1116784
INTRO: Astronomers have long debated why so many icy objects in the outer solar system look like snowmen. Michigan State University researchers now have evidence of the surprisingly simple process that could be responsible for their creation.
Far beyond the violent, chaotic asteroid belt between Mars and Jupiter lies what’s known as the Kuiper Belt. There, past Neptune, you’ll find icy, untouched building blocks from the dawn of the solar system, known as planetesimals. About one in 10 of these objects are contact binaries, planetesimals that are shaped like two connected spheres, much like Frosty the Snowman. But just how these objects came to be without the help of a magic silk hat was an open question.
Jackson Barnes, an MSU graduate student, has created the first simulation that reproduces the two-lobed shape naturally with gravitational collapse. His work is published in the Monthly Notices of the Royal Astronomical Society.
Earlier computational models treated colliding objects as fluid blobs that merged into spheres, making it impossible to form these unique shapes. Thanks to MSU’s Institute for Cyber-Enabled Research, or ICER, and its high-performance computing cluster, Barnes’ simulations produce a more realistic environment that allows objects to retain their strength and rest against one another.
Other formation theories involve special events or exotic phenomena that, while possible, aren’t likely to happen on a regular basis.
“If we think 10 percent of planetesimal objects are contact binaries, the process that forms them can’t be rare,” said Earth and Environmental Science Professor Seth Jacobson, senior author on the paper. “Gravitational collapse fits nicely with what we’ve observed.” (MORE - details, no ads)
INTRO: Astronomers have long debated why so many icy objects in the outer solar system look like snowmen. Michigan State University researchers now have evidence of the surprisingly simple process that could be responsible for their creation.
Far beyond the violent, chaotic asteroid belt between Mars and Jupiter lies what’s known as the Kuiper Belt. There, past Neptune, you’ll find icy, untouched building blocks from the dawn of the solar system, known as planetesimals. About one in 10 of these objects are contact binaries, planetesimals that are shaped like two connected spheres, much like Frosty the Snowman. But just how these objects came to be without the help of a magic silk hat was an open question.
Jackson Barnes, an MSU graduate student, has created the first simulation that reproduces the two-lobed shape naturally with gravitational collapse. His work is published in the Monthly Notices of the Royal Astronomical Society.
Earlier computational models treated colliding objects as fluid blobs that merged into spheres, making it impossible to form these unique shapes. Thanks to MSU’s Institute for Cyber-Enabled Research, or ICER, and its high-performance computing cluster, Barnes’ simulations produce a more realistic environment that allows objects to retain their strength and rest against one another.
Other formation theories involve special events or exotic phenomena that, while possible, aren’t likely to happen on a regular basis.
“If we think 10 percent of planetesimal objects are contact binaries, the process that forms them can’t be rare,” said Earth and Environmental Science Professor Seth Jacobson, senior author on the paper. “Gravitational collapse fits nicely with what we’ve observed.” (MORE - details, no ads)