Science ❯ Astronomy ❯ Orbital Mechanics

Comet Orbits

Long-period Comets Orbital Periods Long Period Comets 170,000 Year Orbit Lemon Comet Orbit 3I/ATLAS Orbit Close Approaches C/2025 A6 (Lemmon) 1,350-Year Orbit Long-term Visibility Perihelion Retrograde Motion

Rare Comet Pan‑STARRS Now Glows Before Dawn for a Short Northern Viewing Window

The window closes around April 19 perihelion, leaving the comet out of view for Northern Hemisphere skywatchers.

Twin Green Comets Brighten For Best Views Under Next Week’s New Moon