How to see interstellar comet 3I/ATLAS as it swings by Earth one last time

This week marks the final opportunity for backyard astronomers to observe interstellar Comet 3I/ATLAS before it heads back toward the far reaches of space. The comet will pass within 167 million miles of Earth on Friday, December 19, appearing like a bright star in the night sky. For comparison, Mars is currently about 250 million […]