Key Facts

  • Categorized as a Aten-class Asteroid
  • Comparable in size to the U.S. Capitol building (0.41 km diameter)
  • Classified as a Near Earth Asteroid (NEA)
  • Not a Potentially Hazardous Object
  • See orbit simulation


66400 (1999 LT7) is a very small asteroid whose orbit could bring it in close proximity to Earth. NASA JPL has classified 1999 LT7 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.

1999 LT7 orbits the sun every 289 days (0.79 years), coming as close as 0.37 AU and reaching as far as 1.35 AU from the sun. 1999 LT7 is about 0.4 kilometers in diameter, making it larger than 90% of asteroids but tiny compared to large asteroids, comparable in size to the U.S. Capitol building.

No Close Approaches

1999 LT7's orbit is 0.06 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.

Orbital simulations conducted by NASA JPL's CNEOS do not show any close approaches to Earth.

Images and Observations

1999 LT7's orbit is determined by observations dating back to April 21, 1987. It was last officially observed on June 7, 2021. The IAU Minor Planet Center records 492 observations used to determine its orbit.

Accessibility and Exploration

This asteroid is not considered a viable target for human exploration by the NHATS study.

Similar Objects

These objects have orbits that share similar characteristics to the orbit of 1999 LT7:



   or view a random object

Orbital Elements

  • Epoch: 2459396.5 JD
  • Semi-major axis: 0.8554 AU
  • Eccentricity: 0.5724
  • Inclination: 9.07°
  • Longitude of Ascending Node: 79.83°
  • Argument of Periapsis: 341.36°
  • Mean Anomaly: 187.39°

Physical Characteristics

  • Diameter: 0.41100 km
  • Magnitude: 19.2
  • Albedo: 0.182

Derived Characteristics

  • Orbit Period: 289 days (0.79 years)
  • Avg. Orbit Speed: 32.20 km/s
  • Aphelion Distance: 1.35 AU
  • Perihelion Distance: 0.37 AU

Map Comparison

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Orbit Simulation

Sky Map

The position of 66400 (1999 LT7) 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 1999 LT7 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.