[1] Alvarez is a Mars-crossing asteroid, a dynamically unstable group between the main belt and the near-Earth populations, crossing the orbit of Mars at 1.66 AU.
12807),[12] just a few months after the naming was announcement on the occasion of the second Conference on Global Catastrophes in Earth History, held in October 1987 at Snowbird, Utah.
[2] In September 2004, a rotational lightcurve of Alvarez was obtained from photometric observations by American photometrist William Koff at the Antelope Hills Observatory (H09) in Bennett, Colorado.
Lightcurve analysis gave a longer-than-average rotation period of 33.42±0.02 hours with a small brightness amplitude of 0.06±0.02 magnitude (U=2), indicative of a spherical rather than elongated shape.
[8][6] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.057 and derives a diameter of 18.43 kilometers based on an absolute magnitude of 12.4.