Interstellar comet 3I/ATLAS shows signs of extreme cold and ancient origin

Astronomers have identified unique chemical signatures in the interstellar comet 3I/ATLAS, suggesting it formed in an extremely cold environment far from its home star. Observations from the William Herschel Telescope and the Very Large Telescope indicate the presence of large quantities of nitrogen and methanol, with temperatures during its formation estimated to be below –240°C.

Research led by teams from Northumbria University, American University, and the University of Edinburgh suggests the comet may be significantly older than our solar system, potentially twice its age of 4.6 billion years. This conclusion is based on isotopic ratios of carbon and nitrogen, which act as cosmic indicators of temperature and age.

Using the Atacama Large Millimeter/submillimeter Array (ALMA), scientists also detected exceptionally high concentrations of methanol. Unlike typical solar system comets, the methanol in 3I/ATLAS appears to be released from both the nucleus and tiny ice particles dispersed throughout the coma. 3I/ATLAS is the third confirmed interstellar object detected, following 1I/’Oumuamua and 2I/Borisov.