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Near-Earth Object

2021 BJ3

NASA ID: 54107791

Safe

2021 BJ3 will pass Earth on 4 February 2027 at a distance of 6.47 lunar distances (LD) - about 2,485,355 km - travelling at 39,684 km/h. Its estimated diameter is between 25 and 57 metres, roughly the size of a football pitch (around 105 m long). NASA does not classify it as potentially hazardous.

Close Approach Date

4 February 2027

In 229 days

Miss Distance

6.47 LD

2,485,355 km

Moon PHA limit

6 times the Moon's distance from Earth

Velocity

39,684 km/h

ISS

1.4 times the orbital speed of the International Space Station

Est. Diameter

25–57 m

Absolute Magnitude

H = 25.1

The brightness measure astronomers use to estimate size

Hazard Classification

Not Hazardous

The real orbit in 3D

The actual path of 2021 BJ3 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 BJ3 to Earth between 1966 and 2033, 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.

1970 1980 1990 2000 2010 2020 2030 1 LDMoon's orbit 10 LD today 6 Feb 1966 - 5.39 LD10 Feb 1978 - 22.06 LD11 Jan 1997 - 27.97 LD21 Jan 2009 - 17.01 LD27 Jan 2015 - 13.77 LD31 Jan 2021 - 9.68 LD4 Feb 2027 - 6.47 LD (this approach)5 Feb 2033 - 5.62 LD Close approach date Miss distance (LD, log scale)

Size Comparison

Asteroid 25–57 m Football pitch 105 m long

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 →

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