The James Webb shows the first ‘snapshot’ of the ice in the Solar System formed 5,000 million years ago

OVIEDO, December 19. () –

The space telescope James Webb has captured the first snapshot of the ice in the Solar System formed ago 5 billion years. This discovery is part of the project DiSCo, focused on the study of the distribution of ice and dust in the Solar Systemled by the researcher from the Institute of Space Sciences and Technologies of Asturias (ICTEA) of the University of Oviedo, Noemí Pinilla-Alonso.

The results of the studies carried out by this researcher have just been published in ‘Nature Astronomy’a magazine with maximum impact in its area of ​​knowledge.

Pinilla-Alonso highlights in a press release that, thanks to the space telescope, the most recent studies of trans-Neptunian objects (TNOs) – entities of the solar system whose orbit is located partially or totally beyond the orbit of the planet Neptune – have revealed how The current diversity of their colors and surface reflectance dates back to their formation sites in the earliest moments of the Solar System. and how these objects change today when they are processed by solar heat as they approach warmer regions.

“The importance of this discovery lies in the fact that we can now affirm that the most determining factor in the current surface composition of these bodies is the material available in the presolar disk at the time of the formation of the planetesimals, solid objects with a diameter greater than one kilometer. “In this way, the current state of these trans-Neptunian objects is closely linked to the ice inventory at the birth of the Solar System, as if it were a frozen snapshot of that time.”explained the researcher.

For the first time, researchers have identified the specific molecules responsible for the remarkable diversity of spectra, colors and albedo observed in these objects. “We have discovered that trans-Neptunian objects can be classified into three different compositional groups, defined by the retention lines of ices such as water, carbon dioxide, methanol and processed organic materials that existed when the Solar System formed thousands of years ago. millions of years,” says Pinilla-Alonso.

These results represent the first clear connection between the formation of planetesimals in the protoplanetary disk and their subsequent evolution. Furthermore, these compositional groups are not homogeneously distributed among objects with similar orbits.”The study sheds light on the relationship between currently observed spectral and dynamical distributions, and how these originated in a planetary system shaped by complex dynamical evolution.“, assured Pinilla-Alonso.

STUDY ON THE CENTAURS

In a complementary study on Centaurs, rare celestial objects by peculiarities, published in the same issue of Nature Astronomy, researchers have found greater compositional diversity than expected, marked by the presence of a layer of dust on their surfaces.

The work shows that the Centaurs, which are TNOs whose orbit has moved towards the region of the giant planets after a close gravitational encounter with Neptune, show a notable modification in their surfaces in the form of a dust blanket, which reveals how these objects Ice creams change as they warm up as they approach the Sun. This phenomenon suggests a thermal evolution due to their transit to the warmest regions of the Solar System. Additionally, researchers have identified a new class of surface on Centaurs, not found among trans-Neptunian objects, and which shows many similarities to the surfaces of comets and active asteroids in the inner Solar System.

“Our finding suggests that Centaurs are not a homogeneous group, but rather dynamic and transitional objects, whose compositional differences reflect different evolutionary stages.“explains the ICTEA researcher, beneficiary of the ATRAE program at the University of Oviedo.

ICE AND GAS IN THE CENTAURO (2060) CHIRON

Professor Pinilla-Alonso is also the author of a study that has just been published in the journal ‘Astronomy & Astrophysics’ and which presents unprecedented observations of the centaur (2060) Chiron made with the James Webb space telescope. This work reveals a complex mixture of molecules on its surface and coma. The detections include gases such as methane (CH4) and carbon dioxide (CO2), as well as various volatile ices, and offer new clues about the activation mechanisms under low temperature conditions.

The results suggest that CH4 release could be driven by a phase transition in amorphous water ice, rather than the traditionally proposed crystallization. Furthermore, CO is observed to be present only as ice, raising questions about its sublimation and storage. These findings expand knowledge of centaurs and highlight Chiron’s role as a natural laboratory for studying the evolution of objects in the outer Solar System.

Pinilla-Alonso has developed the last nine years of her research career at the Florida Space Institute of the University of Central Florida and is also a collaborating expert with NASA. She leads an ambitious project at the University of Oviedo focused on the study of the distribution of ice and dust on the surfaces of minor bodies in the Solar System using precisely the James Webb space telescope.

Observations from this telescope will allow us to explore ice populations beyond Neptune, revealing compositional information that has remained hidden for decades.