Hubble identifies asteroid 44 Nysa as largest bright E-type with irregular shape

The asteroid designated 44 Nysa, named after the mythic valley where Dionysus was said to have been raised by nymphs, resides in the main belt between Mars and Jupiter. Recent observations with the Hubble Space Telescope have confirmed that Nysa is the largest and brightest member of the rare “E‑type” class of asteroids, whose surfaces are composed of highly reflective, enstatite‑rich material—a composition that parallels a few uncommon meteorite types recovered on Earth.

Modeling of Nysa’s light curve, which tracks the variations in its brightness as the body rotates, suggests the asteroid possesses an elongated, asymmetrical shape, a characteristic often observed in sizable asteroid pairs. The combination of its exceptional size, high albedo, and distinctive form provides astronomers with a valuable laboratory for studying the formation and evolution of enstatite‑rich bodies in the early solar system.