Rusty Heart of an Interstellar Comet Makes It Shine ⚡ экспресс
3I/ATLAS is the second confirmed interstellar object. Its presumed high mechanical strength and metal abundance are supported by photometric and spectroscopic data: comparison with primitive carbonaceous chondrites (from NASA's Antarctic meteorite collection) revealed spectral similarities, pointing to a carbon-rich composition with traces of native metals. As it neared perihelion, signs of aqueous alteration and cryovolcanism were recorded, akin to processes on trans-Neptunian bodies. Corrosion reactions of fine metal particles within the ice matrix initiate Fischer–Tropsch synthesis, generating chemical compounds in the coma that are rare for Solar System comets — a direct consequence of the object's metal content, which is atypical for bodies formed in the outer system. Studying such interstellar messengers opens a path to understanding the physico-chemical evolution of distant objects, from the Kuiper belt to the Oort cloud.
The second interstellar guest, comet 3I/ATLAS, shines unusually due to rusting metal grains in its icy core. As it gets closer to the Sun, it behaves like an old tin can tossed into a fire: the heat melts the ice, water seeps into the metal, and vigorous corrosion begins. In its depths lies water ice, carbonaceous compounds, and metallic dust — a legacy of distant stars.
Corrosion kicks off a chemical conveyor belt: simple gases give birth to complex hydrocarbons. This "rusty soup" makes the glowing envelope unusual. As it heats up, the comet erupts with icy geysers, spewing this mixture into space. Using spectroscopy (breaking light into colors) and photometry (measuring brightness), astronomers determined that the comet's chemical fingerprint matches the composition of ancient meteorites found in Antarctic ice.
Interstellar wanderers are rare. They offer a glimpse into the past: similar icy bodies lurk beyond Neptune and in the Oort cloud. Cosmic dust, from which all this was born, is still full of chemical mysteries.
🎯 3I/ATLAS is only the second confirmed interstellar object after ʻOumuamua, spotted in 2017.