Bennu (Asteroid)
484 m (1,588 ft)
Effective (mean) diameter
The spinning-top asteroid NASA's OSIRIS-REx brought samples back from. About 484 m across, a little taller than the Empire State Building.
Published
How big is that?
484 m is 1.5 times the Eiffel Tower and 5.5% of Mount Everest.
Bennu is the 11th smallest of the 39 Cosmic Scale objects, and the 30th largest of the 109 objects across all three SizeItUp games.
Closest in size from the other games: Empire State Building (Classic), 443.2 m tall and Burj Khalifa (Classic), 828 m tall.
Size comparison
To scale, smallest to largest: Bennu in orange beside the Cosmic Scale objects nearest in size, in teal.
| Object | Size | vs Bennu |
|---|---|---|
| Saturn V (Moon rocket)The rocket that carried Apollo astronauts to the Moon. | 111 m tall | 23% of the size |
| Starship (Full stack)SpaceX's giant rocket: the Ship on top of the Super Heavy booster. | 124 m tall | 26% of the size |
| Bennu (Asteroid) | 484 m across | – |
| Mount Kilimanjaro (Earth)Africa's highest mountain, measured above sea level. | 5,895 m tall | 12× bigger |
| Mount EverestEarth's highest mountain, measured above sea level. | 8,848.86 m tall | 18× bigger |
In other units
| Metres | 484 |
|---|---|
| Kilometres | 0.484 |
| Feet | 1,588 |
| Yards | 529.3 |
How it's measured
Effective (mean) diameter. JPL Small-Body Database (Daly et al. 2020).
This body is lumpy rather than round, so its size is given as an effective diameter: the width of a sphere with the same volume.
Sources
- ssd.jpl.nasa.gov: 101955 Bennu: effective body diameter 0.48444 km.
- science.nasa.gov (supporting): NASA: a diameter of 492 meters.
Checked against the source on .
Could you have guessed it by eye?
Bennu is one of the objects in Cosmic Scale, a daily size comparison game: you stretch a shape to the size you think is right beside one you know.