A newly discovered celestial visitor, Comet C/2025 R2 (SWAN), is expected to pass by Earth on October 21, offering stargazers across the globe a rare chance to witness a glowing comet visible even to ...

Later this month, two green comets are forecast to become visible — possibly to the naked eye — in an extremely rare double-act. The brightness of comets is famously difficult to predict, but these ...

If you’ve not seen the two green comets yet, 90 minutes after sunset on Sunday, Oct. 26, is your last best chance before they fade. The brighter Comet Lemmon (C/2025 A6) and much dimmer Comet SWAN ...

While Comet C/2025 R2 (SWAN) made its closest pass to Earth on October 20, 2025, at a distance of approximately 39.1 million kilometers (0.26 AU), it remains a visible, albeit challenging, target for ...