Bennu

Key Facts

• Categorized as a Apollo-class Asteroid
• Comparable in size to the U.S. Capitol building (0.48 km diameter)
• Will pass within 14,767,529 km of Earth in 2037
• Classified as a Near Earth Asteroid (NEA)
• Classified as a Potentially Hazardous Asteroid (PHA)
• See orbit simulation

Overview

Bennu is a very small asteroid whose orbit crosses the orbit of Earth. NASA JPL has classified Bennu as a "Potentially Hazardous Asteroid" due to its predicted close pass(es) with Earth.

Bennu orbits the sun every 437 days (1.20 years), coming as close as 0.90 AU and reaching as far as 1.36 AU from the sun. Bennu is about 0.5 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.

The rotation of Bennu has been observed. It completes a rotation on its axis every 4.30 hours.

Bennu's spectral type None (Tholen) / B (SMASSII) indicates that it is likely to contain hydrogen, nitrogen, ammonia, and iron.

Close Approaches

Bennu's orbit is 0.00 AU from Earth's orbit at its closest point. This means that its orbit is relatively close to Earth's orbit.

Bennu has 15 close approaches predicted in the coming decades:

NASA Sentry has assessed impact risk for 157 very close approach scenarios. Here are the top scenarios ordered by probability of impact:

Images and Observations

Bennu's orbit is determined by observations dating back to Sept. 11, 1999. It was last officially observed on Oct. 3, 2020. The IAU Minor Planet Center records 554 observations used to determine its orbit.

Scientists have been able to determine this object's shape:

View asteroid Bennu in 3D.

Accessibility and Exploration

Bennu can be reached with a journey of 362 days. This trajectory would require a delta-v of 6.995 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 47,757 potential trajectories and launch windows to this asteroid.

See more at the NHATS Mission Trajectories table for Bennu.

Similar Objects

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

• 7822 (1991 CS)
• 138947 (2001 BA40)
• 152671 (1998 HL3)

References

• JPL Small Body Database
• Mission Design
• Sky Finder Chart

Orbit Simulation

Sky Map

The position of Bennu 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 Bennu 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.