Universe Guide

Home / Facts


Sedna is a Kuiper Belt object, a large rock that orbits round outside the orbit of Neptune. It has been categorised as a Trans-Neptunian object. Its mass is estimated/calculated at being 1.7-6.1x10^21 kg. Its name is derived from Inuit Goddess of the Underworld. It has an alternative name which is 2003 VB12. Its density has been calculated at being 2.0 g/cm2. It was discovered on 14 November 2003 by M.Brown, C. Trujillo, D. Rabonowitz. Its orbit takes 4108714.108 d (11249.05 a)` years to travel round the Sun. Its takes 0.42 d (10 h) to do a full rotation period.

The absolute magnitude of the object is 1.6 which is the brightness of the object. A higher absolute magnitude means that the object is faint whereas a very low number means it is very bright.

The albedo of the object is 0.2. The Albedo is the amount of radiation that is reflected back into space by the object.

The Aphelion of the object is 928.048 A.U. which is the point in the orbit that is furthest from the object that it is orbit. At this point, it will then return back to the orbit target. The Perihelion of the object is 11374.298 GM (76.032 AU) A.U. which is the point in the orbit that is closest to the object that it is orbit around. The Longitude of Ascending Node of the object is 144.544 degrees. The Argument of Perihelion is 311.468. It is the angle along the orbit of a planet or other Solar System object as measured from the ascending node (analogous to right ascension and longitude) Ref:Hawaii.

The mean anomoly is 357.713, is the angular distance of the planet from the perihelion or aphelion. Ref:Dictionary.The Semi-Major Axis of the orbit is 75104.117 GM ( 502.040 AU ), which is the furthest point from the centre to the edge of an elliptical point.

The mean temperature of the object is -12 K.

The mass of the object is calculated at being 1.7-6.1x10^21 kg. The surface gravity of the said item is 0.33-0.50 m/s2.

The orbital inclination, the angle at which Sedna orbits in relation to the orbital plane is 11.932 degrees. The orbital eccentricity is 0.849, it is the degree at which Sedna orbits close to a circular (0) orbit as opposed to an elliptical (1) orbit.

Sedna Facts

TypeKuiper Belt Object
Mass1.7-6.1x10^21 kg
Name OriginInuit Goddess of the Underworld
Alternative Name2003 VB12
Density2.0 g/cm2
Date of Discovery14 November 2003
DiscovererM.Brown, C. Trujillo, D. Rabonowitz
Orbital Period4108714.108 d (11249.05 a)`
Rotation Period0.42 d (10 h)
Absolute Magnitude1.6
Aphelion (Furthest)928.048 A.U.
Perihelion (Nearest)11374.298 GM (76.032 AU) A.U.
Longitude Of Ascending Node144.544
Argument of Periphelion311.468
Mean Anomoly357.713
Semi-Major Axis75104.117 GM ( 502.040 AU )
Mean Surface Temperature-12 K
Mass1.7-6.1x10^21 kg
Surface Gravity0.33-0.50 m/s2
Orbital Inclination11.932
Orbital Eccentricity0.849

Add a Comment

Email: (Optional)