New Picture Reveals Evidence of Movement on 3I/ATLAS

A rare interstellar object, 3I/ATLAS, is speeding through our solar system, prompting astronomers to intensify observations. Believed to be a comet, the object is predicted to make its closest approach to Earth in December and to Jupiter in March of next year. Despite numerous observations using both ground-based and space telescopes, many mysteries remain: what is its composition, size, and origin?

Last month, the European Space Agency (ESA) employed five scientific instruments aboard its Jupiter Icy Moons Explorer (JUICE) spacecraft to study the objects properties. JUICE performed a flyby of Venus in August to gain momentum for its decade-long journey to explore Jupiters icy moons.

While awaiting the detailed scientific data, JUICEs navigation camera (NavCam) captured a preliminary image of 3I/ATLAS on November 2, just two days before the spacecrafts closest approach to the object at 41 million miles and three days after its perihelion near the Sun. ESA scientists reported being surprised to observe clear signs of activity as the object warmed under solar radiation.

The NavCam, designed primarily for navigating Jupiters moons rather than high-resolution imaging, revealed the comet-like objects glowing coma. Even with only a fraction of the image transmitted, the team could discern a faint indication of two tails: a plasma tail composed of charged gas pointing away from the Sun, and a subtler dust tail curving along the objects trajectory.

As 3I/ATLAS neared its closest point to the Sun in October, astronomers noticed the plasma tail lengthen significantly, consistent with typical comet behavior as solar heating causes sublimation of ices. This presents a rare chance to study a visitor from another star system, as 3I/ATLAS is only the third interstellar object observed passing through our solar system.

JUICEs suite of five instruments will eventually provide high-resolution multispectral and hyperspectral imaging, ultraviolet and submillimeter wave measurements, and particle spectrometer data to better understand the objects nature. However, the results are not expected until late February 2026 due to data transmission constraints caused by the spacecraft using its main antenna as a heat shield, leaving a smaller antenna to relay data at a slower rate.

Author: Connor Blake