Eros

Artist's impression of the NEAR spacecraft in orbit of the asteroid Eros. NEAR spent a year surveying the oddly-shaped asteroid, taking thousands of close-up pictures and gathering information about its physical properties.

In astronomy, asteroid discovered in 1898 by German astronomer Gustav Witt. It was the first asteroid to be discovered that has an orbit coming within that of Mars. It passes within 22 million km/14 million mi of the Earth. It is elongated, measures 33 × 13 × 13 km/21 × 8 × 8 mi, rotates around its shortest axis every 5.3 hours, and orbits the Sun every 1.8 years.

NASA's Near-Earth Asteroid Rendezvous spacecraft went into orbit around Eros on 14 February 2000. Pictures showed the asteroid to be heavily cratered, indicating that it is probably older than was previously thought. The surface was discovered to contain aluminium, iron, magnesium, and silicon.