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Comet C/2025 R2 Set to Dazzle Sky Gazers in October

10/3/2025

35 3 Full Breakdown

Summary

Comet SWAN Visibility

Comet C/2025 R2 (SWAN) could become naked-eye visible in October for observers worldwide.
Discovered by NASA’s SWAN instrument; orbital period about 22,500 years.
Magnitude 5.9 now; best viewing after Oct 10, peaking around Oct 20.
Look to the southwestern horizon after sunset; binoculars aid visibility.
Brightness may vary, and tracking tools can help observers monitor the path.

Summary

Comet 3I/ATLAS Encounter

Comet 3I/ATLAS, discovered by the ATLAS telescope in July 2023, will pass within 18 million miles of Mars on October 3, 2025, at 193,000 mph.
Its Sun approach is expected on October 30, 2025, at about 130 million miles.
Mars and Jupiter missions will yield observations; the James Webb Space Telescope estimates its mass at 33 billion tons.

History

Historical Context

The Great Comet of 1811, discovered by William Herschel, dazzled observers with its brightness, reaching a magnitude of -2, making it visible even during the day. This comet's appearance sparked public interest in astronomy, paralleling the anticipated visibility of Comet C/2025 R2, which may peak at magnitude 5.9, highlighting humanity's enduring fascination with celestial events.

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Comet SWAN Visibility

Comet C/2025 R2 (SWAN) could become naked-eye visible in October for observers worldwide.
Discovered by NASA’s SWAN instrument; orbital period about 22,500 years.
Magnitude 5.9 now; best viewing after Oct 10, peaking around Oct 20.
Look to the southwestern horizon after sunset; binoculars aid visibility.
Brightness may vary, and tracking tools can help observers monitor the path.

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