Near-Earth asteroid EROS

Eros

Near-Earth asteroid

An elongated near-Earth asteroid, Eros was the first asteroid orbited and landed on by a spacecraft.

View in the 3D observatory

Illustrative surface and shape · Image credits

Equivalent diameter: 16.84 km
Orbital semimajor axis: 1.458 AU
Model orbital period: 1.761 yr

01 / Overview

Meet Eros

Eros is far from spherical. Its elongated form shows how a small body’s gravity may be too weak to pull it into a round shape.

Shape and composition

Eros is about 34 kilometres along its longest axis; its volume-equivalent diameter is much smaller than that length.

Discovery and exploration

NEAR Shoemaker entered orbit around Eros in 2000 and landed in 2001.

02 / Key data

Core parameters

Equivalent diameter: 16.84 km
Orbital semimajor axis: 1.458 AU
Model orbital period: 1.761 yr
Rotation period: 5.27 hours
Orbital inclination: 10.829 °
Orbital eccentricity: 0.22288

Data and calculation notes

Asteroid positions use epoch-based JPL orbital snapshots and a two-body approximation. Planetary perturbations and thermal radiation effects are omitted; this is not for close-approach or impact prediction. Except for Ceres's observed near-spherical fallback, scene shapes come from mission or PDS models. True sizes use equivalent radii; asteroids do not participate in eclipse calculations.

03 / Further reading

A closer look

Scale and orbit4

Eros has an equivalent diameter of about 16.84 km: the diameter of a sphere with the same volume.
A year on Eros lasts about 1.76 Earth years.
Using this site's orbital elements, Eros is about 1.133 AU from the Sun at perihelion.
Using this site's orbital elements, Eros is about 1.783 AU from the Sun at aphelion.

Sources

Understanding the orbital model2

An orbital snapshot describes motion near its epoch; planetary gravity changes real orbits over time.
Near-Earth asteroid is an orbital classification; it does not mean an impact on Earth is imminent.

Sources

04 / Sources

Trusted sources

NASA Science — Eros JPL — Orbital data

Image credits

Published global maps or surface-albedo data are applied only to the matching body. Pallas uses Carry et al.'s published K-band relative-albedo map, which covers about 80% of the surface; unobserved pixels are filled with the mean only to keep the matching model continuous. Psyche uses the per-facet relative-albedo map bundled with DAMIT model 1806. Juno has no downloadable global albedo map, so it keeps its own shape, JPL geometric albedo, and spectral material without borrowing another body's texture.

Surface texture：NEAR / Phil Stooke / NASA PDS · License · Rendered by ORBIT