On the evening of October 2, 2025, the 3I/ATLAS comet was observed and photographed by the High Resolution Imaging Science Experiment, or HiRISE, which is led by the Lunar and Planetary Laboratory and has been photographing the Martian surface for nearly two decades.

  The OSIRIS-APEX (Origins, Spectral Interpretation, Resource Identification, and Security – Apophis Explorer) spacecraft swung by Earth within 2,136 miles before heading into deep space for another trip around the sun.

For more than 1,000 years, the 2-mile-wide chunk of rock and ice lurked in the depths of space, hurtling towards the dim, distant sun. All that time, nobody knew it existed – until January 3, 2025. Catalina Sky Survey director Carson Fuls spoke about what it is like to discover a comet nobody will ever see again in their lifetimes.