Namaka, formal designation (136108) Haumea II, is the smaller, inner moon of the trans-Neptunian

dwarf planet A dwarf planet is a small planetary-mass object that is in direct orbit around the Sun, massive enough to be hydrostatic equilibrium, gravitationally rounded, but insufficient to achieve clearing the neighbourhood, orbital dominance like the ...

Haumea Haumea ( minor-planet designation: 136108 Haumea) is a dwarf planet located beyond Neptune's orbit. It was discovered in 2004 by a team headed by Mike Brown of Caltech at the Palomar Observatory, and formally announced in 2005 by a team heade ...

. Discovered in 2005, it is named after Nāmaka, the goddess of the sea in Hawaiian mythology and one of the daughters of

. Namaka is notable for its unusual, highly-perturbed orbit that is heavily influenced by the larger, outer moon Hiiaka.

Discovery

Namaka was discovered on 30 June 2005 and announced on 29 November 2005. It was nicknamed " Blitzen" by the discovery team before being assigned an official name.

Physical characteristics

Namaka is only 1.5% as bright as its parent dwarf planet Haumea and is about 0.05% its mass. If it turns out to have a similar

albedo Albedo ( ; ) is the fraction of sunlight that is Diffuse reflection, diffusely reflected by a body. It is measured on a scale from 0 (corresponding to a black body that absorbs all incident radiation) to 1 (corresponding to a body that reflects ...

, it would be about 170 km in diameter. Photometric observations indicate that its surface is made of water ice. Mutual events between 2009 and 2011 were expected to improve the knowledge of the orbits and masses of the components of the Haumean system, but interpreting those observations was greatly complicated by the unexpected non-tidally locked spin state of Hiiaka, the larger moon. Namaka is similar in size to

Makemake Makemake ( minor-planet designation: 136472 Makemake) is a dwarf planet and the largest of what is known as the classical population of Kuiper belt objects, with a diameter approximately that of Saturn's moon Iapetus, or 60% that of Pluto. It ...

's moon MK2, despite being smaller. Further observations of Hiiaka might allow to determine its rotation period and spin state more precisely, at which point it should be possible to remove its effect from the data obtained in 2009.

References

{{Solar System moons (compact) Moons of Haumea Trans-Neptunian satellites Discoveries by Michael E. Brown Discoveries by Chad Trujillo Discoveries by David L. Rabinowitz

Discovery

Physical characteristics

See also

References