Neptune and Its Smallest Moon Hippocamp (Artist's Impression) (image) ESA/Hubble Information Centre Share Print E-Mail Caption This artist's impression shows the outermost planet of the solar system, Neptune, and its small moon Hippocamp. Hippocamp was discovered in images taken with the NASA/ESA Hubble Space Telescope. Credit ESA/Hubble, NASA, L. Calçada Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.