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Bennu · radar mean diameter: size, dimension and comparison

The adopted reference is about 492 m.

Radar mean diameter ≈ 492 m · 2013 reference

492 m = 0.492 km. A meter contains 100 centimeters, or 1,000 millimeters.

The asteroid sampled by OSIRIS-REx.

Explore at this scale
Bennu · radar mean diameter, interpreted illustration
Interpreted illustration · dimension stated in the fact sheet.

What does this number measure?

The radar shape published by Nolan et al. in 2013 and archived in NASA's Planetary Data System gives a mean diameter of 492 ± 20 m. This dated reference is used here for comparison; close-up measurements by OSIRIS-REx subsequently refined the shape and volume. The mean diameter is not each of the maximum dimensions of this irregular shape. The silhouette is a detailed interpretation of its spinning-top shape and surface boulders.

Compare the stated dimensions

The comparison uses the number in each fact sheet: altitude, height, diameter, length or distance, depending on the reference. Two values in metres do not necessarily describe the same property.

Compare with Ryugu · reference diameter in the explorer →

Source and limitations

2013 radar reference: ±20 m; later measurements are more precise. Mean size, not a maximum axis.

Uncertainty stated in the catalogue: about 20 m.

Detailed interpretation of Bennu, not a photograph. The reference width is assigned the mean radar diameter from 2013; this silhouette does not measure every maximum axis or boulder of the irregular shape.