42091

42091 is a minor planet in the outer region of the asteroid belt, orbiting the Sun between Mars and Jupiter. It was discovered on February 24, 1999, by astronomers at the Lowell Observatory Near-Earth-Object Search (LONEOS) in Flagstaff, Arizona. The asteroid is classified as a main-belt asteroid, with a semi-major axis of approximately 3.1 astronomical units (AU), indicating its typical distance from the Sun.

42091 has an orbital period of about 5.5 Earth years, completing one orbit around the Sun in this timeframe. Its orbit is moderately eccentric, with an eccentricity of around 0.15, meaning it varies in distance from the Sun by about 15% of its average distance. The asteroid's absolute magnitude is estimated to be around 15.5, which suggests a diameter of roughly 2.5 kilometers, assuming an albedo similar to that of typical asteroids.

The rotation period of 42091 is not well-determined, but it is believed to be relatively slow, possibly on the order of several hours. The asteroid's spectral type is not well-characterized, but it is likely to be of the common C-type, which indicates a carbonaceous composition, typical of many asteroids in the outer main belt.

42091 does not have any known moons or companions, and its orbit does not bring it particularly close to any major planets. It is not considered a potentially hazardous asteroid due to its stable orbit and distance from Earth. The asteroid's designation and discovery details are part of the broader effort to catalog and study the numerous small bodies in the solar system, contributing to our understanding of the formation and evolution of the asteroid belt.