Харон сарны гадаргуу дахь уулын нуруудын бүтцийг судалснаар түүний эргэлтийн хурд хэрхэн удааширч байсныг тогтоожээ.
Калифорнийн их сургууль болон ETH Zurich-ийн эрдэмтэн, доктор Ханжан Чэний удирдсан баг Плутоны хамгийн том дагуул болох Хароны хойд хагас бөмбөрцгийн Оз Терра бүсэд судалгаа хийжээ. 2026 оны долдугаар сарын 14-нд “Nature Communications” сэтгүүлд нийтлэгдсэн уг судалгаагаар 200 гаруй километр үргэлжлэх уулын нуруудын хэлбэрийг шинжилсэн байна. Эрдэмтэд эдгээр уулын налуу нь хөрсний шахалтаас үүссэн болохыг тогтоосон нь өмнөх үеийн таамаглалуудаас ялгаатай үр дүн болжээ.
Компьютер загварчлалын үр дүнд Хароны мөсөн бүрхүүл 30–36 км зузаан байх үед уг бүтэц бүрэлдэн тогтсон гэж үзэж байна. Энэхүү үйл явц нь Харон өөрийн эргэлтийн хурдыг аажмаар алдах “tidal despinning” буюу таталцлын хүчээр удаашрах үзэгдлийн үр дүн аж. Эрт цагт Харон 14.3 цаг тутамд нэг бүтэн эргэдэг байсан бол өдгөө Плутонтой таталцлын хувьд түгжигдсэнээр 153.3 цагт нэг удаа эргэдэг болжээ.
Хароны гадаргуу нь 4 тэрбум орчим жилийн настай бөгөөд дэлхийн бусад мөсөн дагуулуудтай харьцуулахад харьцангуй өөрчлөгдөөгүй үлдсэн нь эрдэмтдэд эртний геологийн үйл явцыг судлах ховор боломжийг олгосон байна. Судалгааны багийнхны үзэж буйгаар, дэлхийн хэмжээний агшилт болон эргэлтийн удаашрал нь Хароныг анх үүсэхдээ харьцангуй хүйтэн байсныг гэрчилж байна. Энэхүү нээлт нь нарны аймгийн гаднах мөсөн дагуулуудын эртний хувьслыг ойлгоход чухал ач холбогдолтой юм.
Дэлгэрэнгүйг эх сурвалжаас харах
↓Эх сурвалжийг нээх ↓
A new study suggests Pluto’s largest moon has preserved signs of an ancient process that gradually slowed its rotation. By examining mountain ridges on Charon, researchers found evidence that could reveal how the icy moon evolved billions of years ago.
Charon is one of the oldest-looking worlds in the Solar System. Its surface is thought to be around 4 billion years old, and unlike many other icy moons, it has not been heavily reshaped over time. That makes it an ideal place to search for traces of geological events that would have disappeared elsewhere.
The new research focuses on tidal despinning, a process in which gravitational forces gradually slow a body’s spin. The team believes Charon’s surface still preserves evidence of that ancient slowdown, offering a rare glimpse into what happened during the moon’s earliest history.
Mountain Ridges Hint at An Unexpected Past
The research team, led by Dr. Hanzhang Chen of the University of California, Los Angeles, and ETH Zurich, turned its attention to Oz Terra, a region in Charon’s northern hemisphere.
There, the scientists examined mountain ranges stretching for more than 200 kilometers. Instead of finding signs that the crust had been pulled apart, they found ridges with asymmetric slopes that point to compression.
The study, published on July 14, 2026, in Nature Communications, says these features formed as parts of Charon’s crust became shorter and existing faults absorbed the stress. That idea differs from earlier studies, which suggested the moon mainly experienced global extension linked to cryovolcanism.
“Charon exhibits a topographic dichotomy of rugged northern highlands and smoother southern plains,” Dr. Chen said. He added that “Previous studies proposed that Charon has undergone global extension accompanied by cryovolcanism.”
A Much Faster Spin in Charon’s Early Days
To understand how those ridges formed, the researchers combined geological observations with computer models.
Their work suggests Charon had an ice shell at least 30 to 36 kilometers thick when these structures appeared. The models also indicate that the crust near the equator became about 1% shorter, with the compression concentrated along pre-existing fault lines.
The same models show that Charon likely rotated once every 14.3 hours early in its history. Today, the moon takes about 153.3 hours to complete one rotation, matching the time it takes to orbit Pluto because the two bodies are tidally locked.
The researchers say this large difference supports the idea that Charon gradually lost rotational speed through tidal despinning over a long period.
A Colder Beginning than Expected
The findings also paint a picture of Charon’s earliest days. The researchers found that the combination of global contraction and rotational slowdown fits a scenario in which the moon started out relatively cold, allowing a thick and rigid ice shell to form early in its evolution.
“Our work suggests that Charon’s surface presents an example that records the planetary despinning history, which predates the proposed global extension and cryovolcanism on Charon,” the authors write in the paper.
They add that these two processes together support the idea of a relatively cold beginning for the icy satelitte and help paint a clearer picture of the early evolution of icy satellites in the outer Solar System.
Enjoyed this article? Subscribe to our free newsletter for engaging stories, exclusive content, and the latest news.
