This interstellar comet in visit continues to become more strange

Since the interstellar comet 3i / Atlas entered our cosmic district in July, astronomers have been running to discover its characteristics. Now that the powerful James Webb space telescope has looked at this icy intruder, he seems to be stranger than anyone imagined.

A pre -impression subject to the astrophysical review Letters for Peer Review on Monday August 25 describes the first results of the JWST survey on 3i / Atlas.

A team of astronomers observed the comet with the near infrared spectroscopic instrument of the telescope (Nirspec) to measure the composition of its coma – the gas cloud and the dust that surrounds its nucleus – and determine what leads to its activity. Their surprising discoveries put the origin of 3i / Atlas originally clearer, helping astronomers to retrace the long journey of the comet to our solar system.

3i / Atlas, detected by the telescope of the Atlas study (asteroid with terrestrial impact of the last alert system) on July 1, is only the third interstellar object ever discovered. These celestial bodies come from star systems beyond ours. Studying them offers an overview of the conditions and processes that have shaped these remote systems. In the past two months, researchers have already discovered unprecedented details on this last cosmic visitor.

JWST spy of unusual characteristics

Now JWST has revealed even more distinctive characteristics of 3i / Atlas. Most comets have comas dominated by water, but it is full of carbon dioxide, according to the study. In fact, the researchers found that its carbon dioxide ratio in water is among the highest ever observed in any comet. This may indicate that 3i / Atlas has an intrinsically rich nucleus rich in carbon dioxide, which suggests that it has been formed in an environment with higher radiation levels than our solar system.

Alternatively, the coma dominated by carbon dioxide can indicate that 3i / Atlas has formed near the CO2 ice line in the protoplanetary disc that surrounded its parent star, according to the researchers. It is the distance of a young star where the temperature drops low enough for carbon dioxide to freeze in the ice. In addition, the lack of water in a coma points to unusual surface properties – or perhaps an insulating crust – which can prevent heat from penetrating the frozen core of the comet.

A comet unlike any other

These new discoveries suggest that the comet formed in conditions very different from those of our corner of the galaxy, adding to an increasing list of features which do it unlike everything that has been seen before. Before this JWST survey, astronomers found evidence suggesting that 3i / Atlas is the oldest interstellar comet ever discovered – potentially older than our solar system. This, associated with its trajectory, suggests that it comes from a relatively old and low -metalicity star system in the “thick disc” of the Milky Way – the part of the galaxy which contains 10% of its total stellar mass.

Astronomers have proposed a richness of new amazing information on 3i / Atlas since its discovery, but this is only the beginning. Experts expect this comet to remain observable until mid-2026, offering many research possibilities. The more information scientists gather on this interstellar object, the closer they get to the secrets of its origin.