Jump to content

User:Eurocommuter/test4

From Wikipedia, the free encyclopedia
Psamathe - Neptune X
Discovery [1]
Discovered by S. Sheppard, D. Jewitt
and J. Kleyna
Discovered in September 2003
provisional
designation
S/2003 N1
Mean Orbital elements [2]
Semi-major axis 46,695,000 km
Eccentricity 0.4499
Inclination 137° *
Orbital period 9115 d
(24.96 yr)
Physical characteristics
Mean diameter 28 km [2] **
Rotation period ?
Albedo 0.04 assumed[2]
color light red
B-V=0.60 V-R=0.45[3]
spectral type D [4]

*to the ecliptic **based on the albedo

Psamathe (sam'-ə-thee, IPA: [ʼsæməθi], Latin Psamathē from Greek Ψαμάθη) or Neptune X, is a retrograde irregular satellite of Neptune.

Psamathe was discovered by S.Sheppard, D. Jewiit and J. Kleyna in September 2003. They reported a satellite which proved to be the same as one of the moons also observed by M. Holman and given the provisional designation S/2003 N 1.[5]

It is named after Psamathe, one of the Nereids. [6] [7]

Irregular satellites of Neptune.

Psamathe orbits Neptune at a distance of about 46.7 Gm and remarkably takes almost 25 Earth years to make one orbit. It's diameter is estimated at 28 kilometers, assuming albedo of 0.04.

The diagram illustrates its orbit in relation to other irregular satellites of Neptune. The eccentricity of selected orbits is represented by the yellow segments (extending from the pericentre to the apocentre).

Given the similarity of the orbit's parameters with S/2002 N 4, it was suggested that both irregular satellites could have a common origin in the break-up of a larger moon.[2]

See also

[edit]

Collection of current maps =

[edit]
Collection of availbale maps
[edit]

References

[edit]
  1. ^ Discovery Circumstances (JPL)
  2. ^ a b c d S. Sheppard, D. Jewitt, J. Kleyna A Survey for "Normal" Irregular Satellites Around Neptune: Limits to Completeness, The Astronomical Journal, 132 (2006), pp. 171–176. Preprint.
  3. ^ Grav, Tommy; Holman, Matthew J.; Gladman, Brett J.; Aksnes, Kaare Photometric survey of the irregular satellites,Icarus, 166,(2003), pp. 33-45. Preprint
  4. ^ Tommy Grav and Matthew J. Holman Near-Infrared Photometry of the Irregular Satellites of Jupiter and Saturn,The Astrophysical Journal, 605, (2004), pp. L141–L144 Preprint
  5. ^ M. Holman, JJ Kavelaars, B. Gladman, Grav, Tommy; Fraser, Wesley C; Milisavljevic, Dan; Nicholson, Philip D; Burns, Joseph A; Carruba, Valerio; Petit, Jean-Marc; Rousselot, Philippe; Mousis, Oliver; Marsden, Brian G; Jacobson, Robert A Discovery of five irregular moons of Neptune, Nature, 430 (2004), pp. 865-867. Final preprint(pdf)
  6. ^ Michael E. Brown and Chadwick A. Trujillo (2004). "Direct Measurement of the Size of the Large Kuiper Belt Object (50000) Quaoar". The Astronomical Journal. 127 (7018): 2413–2417. Reprint on Brown's site (pdf)
  7. ^ Jewitt DC. and Luu J. (2004). "Crystalline water ice on the Kuiper belt object (50000) Quaoar". Nature. 432 (7018): 731–3. PMID 15592406. Reprint on Jewitt's site (pdf)
  • Ephemeris (IAU)[1]
  • Mean orbital parameters (NASA)[2]