Namaka (moon)

From Wikipedia, the free encyclopedia
Jump to: navigation, search
2003 EL61 Haumea, with moons.jpg
Namaka is the faint spot near the bottom of the photo, directly below Haumea (center), in this Keck telescope image.
Discovered by Michael E. Brown,
Chad Trujillo,
David Rabinowitz, et al.
Discovery date 30 June 2005
MPC designation Haumea II Namaka
Pronunciation /nɑːˈmɑːkə/ nah-MAH-kə[a]
(136108) 2003 EL61 II,
S/2005 (2003 EL61) 2
Orbital characteristics[1]
Epoch JD 2454615.0
25657±91 km[1]
Eccentricity 0.249±0.015 (in 2009; variable)
18.2783±0.0076 d[1]
Inclination 113.013°±0.075°
13.41°±0.08° relative to Hiʻiaka (in 2008; variable)
Satellite of Haumea
Physical characteristics
Mean radius
~85 km (if albedo is same as primary's 0.7±0.1)
Mass 1.79 ± 1.48×1018 kg[1]
(0.05% the mass of Haumea)
Mean density
(assumed to be near 1 g/cm3)
Albedo 0.8±0.2[2]
Temperature 32±3 K
21.9 (4.6 difference from primary's 17.3)[2]

Namaka is the smaller, inner moon of the dwarf planet Haumea. It is named after Nāmaka, the goddess of the sea in Hawaiian mythology and one of the daughters of Haumea.


Namaka was discovered on 30 June 2005 and announced on 29 November 2005.[3] It was nicknamed "Blitzen" by the discovery team being assigned an official name.

Physical characteristics[edit]

Namaka is only 1.5% as bright as its parent dwarf planet Haumea[4] and is about 0.05% its mass. If it turns out to have a similar albedo, it would be about 170 km in diameter.[2] Photometric observations indicate that its surface is made of water ice.[4]


  1. ^ The Hawaiian pronunciation is [naːˈmɐkə].


  1. ^ a b c d Ragozzine, D.; Brown, M. E. (2009). "Orbits and Masses of the Satellites of the Dwarf Planet Haumea (2003 EL61)". The Astronomical Journal. 137 (6): 4766. arXiv:0903.4213free to read. Bibcode:2009AJ....137.4766R. doi:10.1088/0004-6256/137/6/4766. 
  2. ^ a b c Wm. Robert Johnston (2008-09-17). "(136108) Haumea, Hi'iaka, and Namaka". Retrieved 2008-09-18. 
  3. ^ Green, Daniel W. E. (1 December 2005). "IAUC 8636". 
  4. ^ a b Barkume, K. M.; Brown, M. E.; Schaller, E. L. (2006). "Water Ice on the Satellite of Kuiper Belt Object 2003 EL61" (PDF). The Astrophysical Journal. 640: L87–L89. arXiv:astro-ph/0601534free to read. Bibcode:2006ApJ...640L..87B. doi:10.1086/503159.