Interstellar Comet 3I/ATLAS Shows Wobbling Jets in Rare Sun-Facing Tail, Surprising Astronomers

Interstellar comet 3I/ATLAS may be on its way out, but it's keeping astronomers guessing with its erratic behaviour since the beginning. New observations reveal weird-jittery jets deep inside an unusual sunward-pointing tail, which is called an anti-tail while the comet was passing close to the Sun. These jet structures, stretching up to nearly one million kilometres, were seen shifting in a regular pattern. The discovery provides fresh details about how material escapes from comets that formed around other stars and gives a rare glimpse of an unspoiled visitor from beyond our solar system.

Wobbling Jets and Sun-Facing Anti-Tail Spotted on Interstellar Comet 3I/ATLAS

According to a Space.com report citing the research findings, the wobbling jets were observed to shift every seven hours and forty-five minutes as 3I/ATLAS approached the Sun. Unlike typical comet tails, which are pushed away from the sun, this anti-tail is oriented towards it, the source mentioned. It is the first time such an outgassing has been observed on an interstellar comet, scientists say.

Sun-heated comets shed gas and dust, forming halos and tails; rare anti-tails occur, but moving jets make interstellar 3I/ATLAS unique.

Rotating Interstellar Comet 3I/ATLAS Reveals Faster Spin and Evolving Tail

Researchers monitored the comet on 37 different nights from July to early September 2025, using a robotic telescope located in the Canary Islands. The observations showed the coma changing from a fan-shaped dust cloud into a clearer tail as solar radiation grew stronger during the comet's approach toward the Sun in late October.

Jet motion shows the comet's icy nucleus rotates every 15.5 hours, faster than thought; 3I/ATLAS departs, but its research value endures.