- Object
- Object primary designation
- Close-Approach (CA) Date
- Date and time (TDB) of closest Earth approach. 'Nominal Date' is given to appropriate precision. The 3-sigma uncertainty in the time is given in the +/- column in days_hours:minutes format (for example, '2_15:23' is 2 days, 15 hours, 23 minutes; '< 00:01' is less than 1 minute).
- CA Distance Nominal (LD | au)
- The most likely (Nominal) close-approach distance (Earth center to NEO center), in LD (Lunar Distance) and au.
- CA Distance Minimum (LD | au)
- The minimum possible close-approach distance (Earth center to NEO center), in LD (Lunar Distance) and au. The minimum possible distance is based on the 3-sigma Earth target-plane error ellipse.
- V relative (km/s)
- Object velocity relative to Earth at close-approach.
- V infinity (km/s)
- Object velocity relative to a massless Earth at close-approach.
- H (mag)
- Asteroid absolute magnitude (in general, smaller H implies larger asteroid diameter). Undefined for comets.
- Diameter
- Diameter value when known or a range (min - max) estimated using the asteroid's absolute magnitude (H) and limiting albedos of 0.25 and 0.05.
- au
- One Astronomical Unit (au) is approximately 150 million kilometers (see glossary for definition).
- LD
- One Lunar Distance (LD) is approximately 384,000 kilometers (see glossary for definition).
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