Original: The satellite appears neutral (grey) in the visible light (colour indices B-V=0.77, R-V=0.35), Tommy Grav, Matthew J. Holman, and Wesley C. Fraser Photometry of Irregular Satellites of Uranus and Neptune,The Astrophysical Journal, 613, (2004), pp.
Simplified: The moon appears grey in the visible light, Tommy Grav, Matthew J. Holman, and Wesley C. Fraser Photometry of Irregular Satellites of Uranus and Neptune,The Astrophysical Journal, 613, (2004), pp.