Key Facts

  • Categorized as a Apollo-class Asteroid
  • Comparable in size to a school bus or smaller
  • Will pass within 4,901,212 km of Earth in 2021
  • Classified as a Near Earth Asteroid (NEA)
  • Not a Potentially Hazardous Object
  • See orbit simulation


2021 NL4 is a very small asteroid whose orbit crosses the orbit of Earth. NASA JPL has classified 2021 NL4 as a "Near Earth Asteroid" due to its orbit's proximity to Earth, but it is not considered potentially hazardous because computer simulations have not indicated any imminent likelihood of future collision.

2021 NL4 orbits the sun every 559 days (1.53 years), coming as close as 0.81 AU and reaching as far as 1.84 AU from the sun. Based on its brightness and the way it reflects light, 2021 NL4 is probably between 0.034 to 0.151 kilometers in diameter, making it a small to average asteroid, very roughly comparable in size to a school bus or smaller.

Close Approaches

2021 NL4's orbit is 0.03 AU from Earth's orbit at its closest point. This means that there is an wide berth between this asteroid and Earth at all times.

2021 NL4 has 2 close approaches predicted in the coming decades:

Date Distance from Earth (km) Velocity (km/s)
Aug. 3, 2021 4,901,212 10.086
Dec. 29, 2027 16,399,398 13.298

Images and Observations

2021 NL4's orbit is determined by observations dating back to July 10, 2021. It was last officially observed on July 30, 2021. The IAU Minor Planet Center records 41 observations used to determine its orbit.

Accessibility and Exploration

2021 NL4 can be reached with a journey of 378 days. This trajectory would require a delta-v of 11.474 km/s. To put this into perspective, the delta-v to launch a rocket to Low-Earth Orbit is 9.7 km/s. There are 44 potential trajectories and launch windows to this asteroid.

See more at the NHATS Mission Trajectories table for 2021 NL4.

Similar Objects

These objects have orbits that share similar characteristics to the orbit of 2021 NL4:



   or view a random object

Orbital Elements

  • Epoch: 2459408.5 JD
  • Semi-major axis: 1.327 AU
  • Eccentricity: 0.3897
  • Inclination: 4.02°
  • Longitude of Ascending Node: 331.15°
  • Argument of Periapsis: 51.01°
  • Mean Anomaly: 312.08°

Physical Characteristics

  • Diameter: ~0.093 km
  • Magnitude: 23.56

Derived Characteristics

  • Orbit Period: 559 days (1.53 years)
  • Avg. Orbit Speed: 25.83 km/s
  • Aphelion Distance: 1.84 AU
  • Perihelion Distance: 0.81 AU

Map Comparison

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Orbit Simulation

Sky Map

The position of 2021 NL4 is indicated by a ◯ pink circle. Note that the object may not be in your current field of view. Use the controls below to adjust position, location, and time.

Size Rendering

The below comparison is an artistic rendering that uses available data on the diameter of 2021 NL4 to create an approximate landscape rendering with New York City in the background. This approximation is built for full-resolution desktop browsers. Shape, color, and texture of asteroid are imagined.