Scientists working with the James Webb telescope, the largest telescope in space, have spotted what’s believed to be an incredibly rare interstellar sight.
This is the first time an interstellar comet, 3I/Atlas, has been captured on images and only the third time one has ever been seen.
Travelling towards the sun at speeds of 130,000mph, the comet was first discovered in July. Since then, the scientists have been working to learn all they can about the phenomenon.
No obvious jet, tail, or trail structures were found in the images, so different measures than usual needed to be employed to work out some basic statistics on the comet.
The James Webb telescope, already responsible for impressive feats, can use near-infrared technology to capture the comet, with physical properties then deduced based on the light emitted from it.
Based on that data from the impressive telescope, the team has estimated that the comet is around 3.5 miles wide. If accurate, that would make it one of the largest interstellar objects ever seen.
It’s travelling in what the team describes as an unusually flat and straight line, which is what gives it its extreme speed.
That 130,000mph speed has also led to the conclusion that the comet has been travelling for billions of years, with it said to be around 3 billion years older than our own 4.6 billion-year-old solar system.
A carbon dioxide atmosphere has developed around it, perhaps indicating that the comet was formed near a CO2 ice line of swirling gas. However, it’s unclear where exactly it originated from.
Ordinarily, such a comet would have been expected to give off a bright water gas coma, but the team concluded that it’s most likely that 3I/Atlas is emitting large chunks of mixed CO2+H2O ice into its immediate atmosphere, where evaporative cooling is suppressing the ice’s vapour pressure and creating the unique effect.
