Namaka (moon)

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Namaka
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.
Discovery
Discovered by Michael E. Brown,
Chad Trujillo,
David Rabinowitz, et al.
Discovery date 30 June 2005
Designations
MPC designation Haumea II Namaka
Pronunciation /nɑːˈmɑːkə/ nah-MAH-kə[a]
Alternative names (136108) 2003 EL61 II,
S/2005 (2003 EL61) 2
Orbital characteristics[1]
Semi-major axis 25657 ± 91 km[1]
Eccentricity 0.249 (in 2009; variable)
Orbital period 18 day[2]
Inclination 13° 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)
Rotation period (unknown)
Axial tilt (unknown)
Albedo (unknown)
Temperature 32±3 K
Apparent magnitude 4.6 difference from primary's 17.3[3]

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

Discovery[edit]

Namaka was discovered on 30 June 2005 and announced on November 29, 2005.[4] It was nicknamed "Blitzen" by the discovery team before receiving an official name.

Physical characteristics[edit]

Namaka is only 1.5% as bright as its dwarf planet Haumea[5] and is about 0.05% its mass. If it turns out to have a similar albedo, it would be about 170 km in diameter.[3] Photometric observations indicate that its surface is made of water ice.[5]

See also[edit]

Notes[edit]

  1. ^ The Hawaiian pronunciation is [naːˈmɐkə].

References[edit]

  1. ^ a b c 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:0903.4213. Bibcode:2009AJ....137.4766R. doi:10.1088/0004-6256/137/6/4766.  edit
  2. ^ Brown, M. E.. "Orbits and Masses of the 2003 EL61 Satellite System". Retrieved 2008-10-17. [dead link]
  3. ^ a b Wm. Robert Johnston (2008-09-17). "(136108) Haumea, Hi'iaka, and Namaka". Retrieved 2008-09-18. 
  4. ^ Green, Daniel W. E. (1 December 2005). "IAUC 8636". 
  5. ^ a b Barkume, K. M.; Brown, M. E.; Schaller, E. L. (2006). "Water Ice on the Satellite of Kuiper Belt Object 2003 EL61". The Astrophysical Journal 640: L87–L89. arXiv:astro-ph/0601534. Bibcode:2006ApJ...640L..87B. doi:10.1086/503159.  edit