Nix (moon)

Pluto system 2005 discovery images

Pluto and its satellites (2005)

File:Simulation of Nix Rotation.ogg

A day on Nix

Nix is a natural satellite of Pluto, discovered in June 2005 by the Hubble Space Telescope's Pluto Companion Search Team, which consists of astronomers Hal A. Weaver, Alan Stern, Max J. Mutchler, Andrew J. Steffl, Marc W. Buie, William J. Merline, John R. Spencer, and Eliot J. Young. Nix is one of the five known moons of Pluto, the others being Charon, Hydra, Kerberos, and Styx.

Discovery and Naming

Nix was discovered along with Hydra in June 2005, as the Hubble Space Telescope observed Pluto for any surrounding objects. The discovery was part of a program designed to support the New Horizons mission, which flew by Pluto in July 2015. Nix and Hydra's discovery was announced on October 31, 2005. The moon was initially given the provisional designation S/2005 P 2. The name "Nix" was officially adopted by the International Astronomical Union (IAU) in June 2006, derived from Greek mythology, where Nyx (spelled Nix in the application to the IAU) is the goddess of the night, a fitting name for a moon of Pluto, who is the god of the underworld in classical mythology.

Physical Characteristics

Nix is an irregularly shaped body, with dimensions of approximately 42 x 36 km. Its surface is highly reflective, suggesting that it is covered in water ice, a common feature for objects in the Kuiper Belt. The moon's brightness varies by a factor of 2.7, which might indicate an elongated shape or albedo variations across its surface.

Orbit

Nix orbits Pluto at a distance of about 48,700 kilometers, in a direct, nearly circular orbit. Its orbital period is around 24.9 days, and it is in a mean-motion resonance with Charon, the largest of Pluto's moons. This resonance exerts a significant gravitational influence on the smaller moons, contributing to their orbital stability and possibly affecting their rotational periods.

Exploration

The most detailed images and data on Nix were obtained by the New Horizons spacecraft during its flyby of the Pluto system in July 2015. These observations provided invaluable insights into Nix's shape, surface features, and composition. However, due to the distance and speed of the flyby, the data on Nix is not as comprehensive as that on Pluto and Charon.

Significance

The study of Nix, along with Pluto's other moons, offers important clues about the formation and evolution of the outer solar system. Understanding the dynamics and characteristics of these small moons helps astronomers to build models of how the Kuiper Belt and similar systems throughout the galaxy have developed over billions of years.