US NEWS: Astronomers have unveiled remarkable new photographs of Comet 3I/ATLAS, the third confirmed object ever known to have arrived from beyond our solar system, just weeks before it makes its closest pass by Earth.
The latest images come from two major observatories: NASA’s Hubble Space Telescope and the European Space Agency’s Jupiter Icy Moons Explorer spacecraft, known as Juice. Together, these views are helping scientists piece together the story of this distant traveler that was first discovered racing through our stellar neighborhood in July.
On November 30, Hubble trained its powerful Wide Field Camera 3 on the comet from a distance of roughly 178 million miles, producing the clearest pictures yet of its elongated, teardrop-shaped nucleus.
At almost the same time, the Juice spacecraft, which launched in April 2023 and is currently cruising toward Jupiter for a 2031 arrival, found itself perfectly positioned for an unexpected observation. In early November, while about 41 million miles from the comet, Juice turned five of its science instruments and its navigation camera toward the icy visitor.
Because the spacecraft is currently using its large main antenna as a sun shield, only a smaller backup antenna is available for communication. That limitation slows data transmission dramatically, but mission controllers were eager for a first look. They pulled down a portion of one navigation-camera image that reveals striking activity triggered by the comet’s close brush with the sun in October.
The picture shows a bright coma, the fuzzy envelope of gas and dust that surrounds the solid core, along with two distinct tails. One tail consists of electrically charged plasma pushed straight outward by the solar wind, while the other is a gentler arc of dust particles. Both features are familiar on comets born in our own solar system, and seeing them on an interstellar object provides important clues about its composition.
Comet 3I/ATLAS will reach its nearest point to Earth on December 19 at a safe distance of approximately 167 million miles, on the opposite side of the sun from our planet. It will continue to be a prime target for professional telescopes and passing spacecraft for several more months before it departs the solar system for good.
The full set of Juice observations, including high-resolution images and measurements of gases and particles around the comet, is scheduled to arrive on Earth between February 18 and 20. Researchers say those data could offer the best evidence yet about the distant star system where this rare comet was born.