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90377 Sedna Asteroid Mass, Discovery and other Facts
90377 Sedna (2003 VB12) is a Dwarf Planet, located in the Kuiper Belt, an area of space past the orbit of Neptune. It has been categorised as a Trans-Neptunian object. Sedna's name and number is allocated to it by the Minor Planet Center (MPC), part of the Smithsonian Astrophysical Observatory. Some asteroids are dedicated by the discoverers to people or named after mythology, such as Arawn and Sedna. Those not named will be assigned the year it was discovered and a few letters. Usually, an asteroid will just be referred to as Sedna. Sedna is one of the furthest objects so far discovered in the Solar System. It was given the name Sedna after the Intuit Goddess of the Sea by the discoverers. The name stuck rather than being renamed.
Dwarf Planets
There are five other dwarf planets in the Solar System and all but one orbits in the Kuiper Belt. The odd one out is Ceres which orbits between Mars and Jupiter.
Pluto was downgraded from Planet after a 2006 vote by the I.A.U. on a definition of what a planet was. A planet had to pass three tests.
- Had to orbit a Star
- It had to be of sufficient size for gravity to pull it into a spherical shape.
- Have had to clear its path from other objects.
As Pluto had failed the third test, it was no longer classed as a planet. The decision was a controversial one and one that, although official, some people still refer to Pluto as a planet.
Sedna's mass is estimated/calculated at 1.7-6.1x10^21 kg kg. The origin of Sedna is from Inuit Goddess of the Underworld. Its density has been calculated at being 2.0 g/cm2 g/cm^3. It takes 0.42 d (10 h) to do a full rotation period. Sedna absolute magnitude is 1.54, which is the object's brightness. A higher absolute magnitude means that the object is faint, whereas a very low number means it is very bright. The albedo of the Sedna is 0.2. The albedo is the amount of radiation reflected into space Sedna. Sedna's aphelion is 966.214 A.U. which is the point in the orbit that is furthest from the thing (e.g. the Sun) that it is orbiting. At this point, it will then return to the orbit target. The perihelion of Sedna is 76.384 A.U. which is the closest point that the object will get to the thing that it is orbiting. The mean anomaly of Sedna is 358.4, the object's angular distance from the perihelion or aphelion. Ref: Dictionary.
The Longitude of Ascending Node of Sedna is 144.2 degrees. It is the angle between the Reference Direction and the Ascending Node. It is generally represented by the greek letter Ω. The ascending node is the point at which the object passes north. The descending node is the southern equivalent.
The Argument of Perihelion of Sedna is 310.9. 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 escape velocity of Sedna is 0.62 - 0.95 Km/s km/h. The escape velocity is the speed an object needs to be travelling in order to break free from the objects gravity. The larger an object is, the more velocity (speed) is needed to break free from the object.
Sedna mean temperature is -12 K. The surface gravity of the Sedna is 0.33-0.50 m/s². For comparison, the Earth's surface gravity is 9.807 m/s². The larger an object is, the stronger the surface gravity is.
Orbital Details
Sedna orbital period, the time it takes to complete an orbit of the Sun, is 4108714.108 d (11249.05 a)` years. The orbital inclination of Sedna, the angle at which Sedna orbits to the orbital plane, is 11.9 degrees. The orbital eccentricity is 0.853 of Sedna, the degree at which Sedna orbits close to a circular (0) orbit as opposed to an elliptical (1). The semi-major axis of Sedna orbit is 521.299 (A.U.), the furthest point from the centre to the edge of an elliptical.
Orbital Path
If the white lines are above, then the object's path is under the ecliptic. If the white lines are below, the path is above the ecliptic. This refers to the Inclination of the object. The image was created using N.A.S.A. Solar System Dynamics.
Facts and Figures
| Alternative Name | 2003 VB12 |
| Type | Kuiper Belt Object |
| Number | 90377 |
| Mass | 1.7-6.1x10^21 kg kg |
| Name Origin | Inuit Goddess of the Underworld |
| Density (g/cm^3) | 2.0 g/cm2 |
| Rotation Period | 0.42 d (10 h) |
| Absolute Magnitude | 1.54 |
| Albedo | 0.2 |
| Aphelion (Furthest) | 966.214 A.U. |
| Perihelion (Nearest) | 76.384 A.U. |
| Mean Anomaly | 358.4 |
| Longitude Of Ascending Node | 144.2° |
| Argument of Perihelion | 310.9° |
| Escape Velocity (km/h) | 0.62 - 0.95 Km/s |
| Mean Surface Temperature | -12 K |
| Surface Gravity (m/s²) | 0.33-0.50 m/s2 |
| Orbital Period | 4108714.108 d (11249.05 a)` Yrs |
| Orbital Inclination | 11.9° |
| Orbital Eccentricity | 0.853 |
| Semi-Major Axis | 521.299 A.U. |
| Modified Date | 21st April 2024 |
| Published Date | 9/12/2022 10:16:47 AM |
Selected Kuiper Belt Objects
- 19521 Chaos
- 53311 Deucalion
- 136199 Eris
- 38628 Huya
- 28978 Ixion
- 136472 MakeMake
- 90482 Orcus
- 50000 Quaoar
- 38083 Rhadamanthus
- 20000 Varuna
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