a large rock in the middle of a space filled with stars

Smallest Kuiper Belt Object Detected Caption This is an artist's impression of a one-half-mile-diameter Kuiper Belt Object (KBO) that was detected by NASA's Hubble Space Telescope. The icy relic from the early solar system is too small for Hubble to photograph. The object was detected when it passed in front of a background star, temporarily disrupting the starlight. Credits NASA, ESA, and G. Bacon (STScI)