Asteroids & comets · Near-Earth asteroid

Bennu

Orbits the Sun near Earth · Light crosses it in 1.6 millionths of a second

Across

490 m

Vs Earth

1/26,000 of Earth

Mass

7.3 × 10¹⁰ kg

Open Bennu in Cosmic Scale

About

Bennu is a rubble-pile asteroid about half a kilometre wide: loose rocks and boulders held together by their own feeble gravity. NASA's OSIRIS-REx mapped it for two years, grabbed a sample from its surface in 2020 and returned it to Earth in 2023.

OSIRIS-REx brought 121 grams of it back to Earth in 2023.

At a glance

Size	About 490 m across
Day	4.3 hours
Sample returned	121.6 g, in 2023
Shape	Like a spinning top

Did you know

1. When the spacecraft touched it, the surface gave way like a ball pit; it would have sunk in had it not fired its thrusters.
2. Its sample contains the building blocks of life, including all five bases found in DNA and RNA.
3. It has a small chance of hitting Earth in the late 2100s, about 1 in 2,700.