Near-Earth Object
2021 BC
NASA ID: 54106085
2021 BC will pass Earth on 20 January 2027 at a distance of 131.77 lunar distances (LD) - about 50,651,875 km - travelling at 79,993 km/h. Its estimated diameter is between 37 and 82 metres, roughly the size of a football pitch (around 105 m long). NASA does not classify it as potentially hazardous.
Close Approach Date
20 January 2027
In 209 days
Miss Distance
131.77 LD
50,651,875 km
132 times the Moon's distance from Earth
Velocity
79,993 km/h
2.9 times the orbital speed of the International Space Station
Est. Diameter
37–82 m
Absolute Magnitude
H = 24.3
The brightness measure astronomers use to estimate size
Hazard Classification
Not Hazardous
The real orbit in 3D
The actual path of 2021 BC around the Sun, computed from JPL orbital elements. Drag to rotate, scroll to zoom, and use the time controls to run the orbit forwards or back.
Every recorded pass
Each dot is one close approach of 2021 BC to Earth between 1909 and 2075, from JPL's records. Lower means closer: a dot under the dashed line passed nearer than the Moon. The orange dot is the approach on this page.
Size Comparison
Reading the Numbers
- A lunar distance (LD) is the average gap between Earth and the Moon, about 384,400 km. It is the standard yardstick for close approaches. Read more →
- Diameter estimates come from brightness. A dark surface reflects less light than a bright one, so the true size can sit anywhere in the quoted range. Read more →
- Potentially hazardous is a watch-list label based on size and orbital proximity. It does not mean an impact is expected. Read more →
