As of 1 January 1998, the celestial reference system adopted by the IAU will be based on a set of extragalactic directions, replacing the Fundamental Katalog No 5 (FK5) that gave star coordinates in a reference system (referred to as equator and equinox J2000) based primarily on the dynamics of the solar system. This change is deeper than a mere replacement of a reference system by a better one...

Abstract We report on the discovery by Zwicky Transient Facility of an asteroid orbiting entirely within orbit Venus, first known example this orbital class. The asteroid's perihelion is closer to Sun than aphelion Mercury, and its diameter estimated at about 1.8 km assuming albedo 0.2. object was observed 2020 January 4 in four exposures obtained 7 minutes apart during evening twilight survey....

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