All posts tagged: University of Bern

AI finds 44 star systems that could hide Earth-like planets

AI finds 44 star systems that could hide Earth-like planets

Published by Jenni Sidey

A machine-learning model identified 44 known planetary systems that could contain undiscovered Earth-like planets. Tests reached up to 99% precision on simulated systems, but telescope observations have not confirmed the predicted planets. The approach uses the arrangement of known planets to help astronomers select promising targets for further searches. A planet already found around a distant star may offer clues about another world still hidden nearby. Its mass and orbit can carry traces of how the entire planetary system formed, including planets too small or faint for telescopes to detect. The model reached precision scores of up to 99% when tested on simulated planetary systems. That result measures performance within a computer-generated population. The predicted worlds around actual stars remain unconfirmed, and the method’s value will depend on follow-up observations. The bee swarm plot ranks seven features by importance, with SHAP values showing how strongly each feature influences individual predictions. (CREDIT: Jeanne Davoult et al, Astronomy & Astrophysics) Reading the arrangement of planets Planets form together within disks of gas and solid material surrounding young …

Mars moon Deimos may be hiding ancient craters beneath 120 meters of debris

Mars moon Deimos may be hiding ancient craters beneath 120 meters of debris

Published by Jenni Sidey

A single asteroid impact may explain both Deimos’ huge south-polar depression and the thick blanket of debris covering the Martian moon. Simulations point to a roughly 320-meter asteroid striking at about a 45-degree angle without breaking Deimos apart. Future observations from missions including JAXA’s MMX could test predictions about the moon’s weak surface, porous interior and buried craters. Deimos looks unusually smooth for a battered moon. Its surface is muted by dust and rubble, while a broad depression cuts across its south pole. A new simulation study suggests both features may trace back to the same violent event. The work, published in Nature Astronomy and led by Sabina Raducan, used high-resolution impact simulations developed at the University of Bern. The team found that a single asteroid strike could have excavated the southern depression while spreading debris across nearly the entire moon. Deimos is Mars’ smaller and outer moon, measuring about 12 kilometers across. Unlike heavily cratered Phobos, it is covered by a loose regolith layer that softens older surface features. The south-polar depression spans about …

Astronomers map the climate of Earth-like exoplanets for the first time

Astronomers map the climate of Earth-like exoplanets for the first time

Published by Jenni Sidey

A pair of scorched worlds circling the red dwarf TRAPPIST-1 now offer one of the clearest looks yet at what life may be up against around the most common stars in the Milky Way. Using the James Webb Space Telescope, an international team that included researchers from the University of Bern and the University of Geneva has, for the first time, mapped the climate of rocky exoplanets with masses similar to Earth. Their target was not a giant gas planet or a bloated world with an easy-to-read atmosphere, but two small rocky planets in the famous TRAPPIST-1 system, known as TRAPPIST-1b and TRAPPIST-1c. What they found was stark. The two worlds seem to swing between blistering daylight and brutal cold, with day-to-night temperature differences topping 500 degrees Celsius. That kind of contrast points to a simple conclusion: neither planet appears to have a dense atmosphere capable of moving heat from one side to the other. The result, published in Nature Astronomy, sharpens one of the biggest questions in exoplanet science. Rocky planets around red dwarf …