Comet 3I/ATLAS is drawing unusual attention because it doesn't behave the way most comets do in photographs and time-series imaging. As it heads back out of the inner solar system, astronomers are analysing an odd sunward-pointing dust feature and shifting jet-like structures that appear to change position in a repeating pattern.
The most baffling feature is a prominent 'anti-tail'—a dust stream that appears to extend a million kilometres in the Sun's direction, rather than trailing behind as expected. While such features are rare, the strength and structure of this one have made the comet a top priority for scientists studying interstellar visitors.
