Sky & Observing
Plan your observations of Comet 3I/ATLAS with detailed visibility information, equipment recommendations, and optimal viewing windows.
Important Notice
Telescope Required: 3I/ATLAS is a faint comet with magnitude 11.5-13.6, making it invisible to the naked eye.
Minimum Equipment: Telescope with at least 200mm (8-inch) aperture or advanced CCD imaging setup recommended for visual observation.
Visibility Status
Observable
Currently within optimal observing period
Current Magnitude
12.1
Apparent brightness
Best Viewing Time
02:30 - 05:00
Local time (varies by location)
Visibility Chart
Altitude and azimuth for your location throughout the night
Interactive visibility chart coming soon...
Equipment Recommendations
What you need to observe 3I/ATLAS successfully
Visual Observation
- • 200mm+ (8-inch) telescope minimum
- • Low-power eyepiece (25-40mm)
- • Dark sky location (Bortle 3 or better)
- • Star charts and red flashlight
Photography
- • DSLR or dedicated astronomy camera
- • Telephoto lens (200mm+) or telescope
- • Equatorial mount with tracking
- • Multiple 30-60 second exposures
Observing Tips
Best practices for comet observation
Preparation
- • Check weather conditions and moon phase
- • Allow 20-30 minutes for eye adaptation
- • Use averted vision technique
- • Observe from darkest available location
During Observation
- • Look for fuzzy, non-stellar appearance
- • Note any tail or coma development
- • Compare with nearby stars for magnitude
- • Record observation details and sketches
Key Observing Dates
Important dates for 3I/ATLAS observation
Perihelion
Closest approach to Sun
October 29, 2025
1.36 AU from Sun
Closest to Earth
Best observing opportunity
December 19, 2025
1.8 AU from Earth
Optimal Period
Best overall visibility window
Oct 2025 - Jan 2026
4-month window
Tools & Downloads
Helpful resources for planning your observations