11264 Claudiomaccone

Lore & Background

Claudiomaccone orbits the Sun in the central main-belt at a distance of 2.0–3.2 AU once every 4 years and 2 months (1,512 days). Its orbit has an eccentricity of 0.23 and an inclination of 4° with respect to the ecliptic. It comes closer to Mars than to the other planets, repeatedly approaching the Red Planet as close as 0.47 AU (70,300,000 km), and in 2096 it makes a very rare approach to 65,000,000 km. A first precovery was taken at Palomar Observatory in 1950, extending the body's observation arc by 29 years prior to its official discovery.

According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Claudiomaccone measures 3.203 kilometers in diameter and its surface has a high albedo of 0.432, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony S-type asteroids of 0.20 and calculates a diameter of 4.30 kilometers with an absolute magnitude of 14.2. In November 2004, a rotational lightcurve was obtained by Ukrainian astronomer Yurij N. Krugly, giving a rotation period of 3.1872 hours with a brightness amplitude of 0.15 magnitude. An identical period with an amplitude of 0.12 magnitude was also published by Petr Pravec in 2006. After the binary nature was announced, follow-up observations in 2008 and 2012 gave periods of 3.1873 and 3.18701 hours with amplitudes of 0.16 and 0.12 magnitude, respectively.

The photometric observations from 2004 also revealed that Claudiomaccone is an asynchronous binary system with a minor-planet moon orbiting it every 15.11 hours. An identical orbital period is also given by Pravec. The discovery was announced in December 2005. Based on a secondary to primary mean-diameter ratio of larger than 0.31, the moon's diameter is estimated to be at least 1.24 kilometers, and its orbit has an estimated semi-major axis of 6 kilometers.

Reader's Guide

11264 Claudiomaccone is significant as a binary asteroid system, a relatively rare configuration in the main belt, and for its association with Claudio Maccone, a prominent SETI astronomer. The asteroid's moon, with an orbital period of 15.11 hours and a diameter of at least 1.24 kilometers, was discovered through photometric observations in 2004 and announced in December 2005. The asteroid's high albedo of 0.432, as measured by NEOWISE, contrasts with the standard stony asteroid albedo of 0.20, indicating an unusually reflective surface. Its orbit brings it repeatedly close to Mars, with a particularly rare approach to 65,000,000 km in 2096. The naming honors Maccone's work on the FOCAL space mission concept, which proposes using the Sun's gravitational lensing effect at 550 AU to detect radio signals. The asteroid's discovery by Nikolai Chernykh at the Crimean Astrophysical Observatory and its precovery at Palomar in 1950 highlight its long observational history. The multiple lightcurve measurements, with consistent rotation periods around 3.187 hours, confirm its stable rotation. This binary system contributes to the study of asteroid satellite formation and dynamics.

Did You Know?

• Claudiomaccone is a binary asteroid with a moon that orbits it every 15.11 hours.
• In 2096, it makes a very rare approach to Mars at a distance of 65,000,000 km.