90377 Sedna - Orbit and Rotation

Orbit and Rotation

Sedna has the longest orbital period of any known large object in the Solar System, calculated at around 11,400 years. Its orbit is extremely eccentric, with an aphelion estimated at 937 AU and a perihelion at about 76 AU, the most distant perihelion ever observed for any Solar System object. At its discovery it was approaching perihelion at 89.6 AU from the Sun, and was the most distant object in the Solar System yet observed. Eris was later detected by the same survey at 97 AU. Although the orbits of some long-period comets extend farther than that of Sedna, they are too dim to be discovered except when approaching perihelion in the inner Solar System. Even as Sedna nears its perihelion in mid 2076, the Sun would appear merely as a very bright star in its sky, only 100 times brighter than a full Moon on Earth, and too far away to be visible as a disc to the naked eye.

When first discovered, Sedna was thought to have an unusually long rotational period (20 to 50 days). It was initially speculated that Sedna's rotation was slowed by the gravitational pull of a large binary companion, similar to Pluto's moon Charon. A search for such a satellite by the Hubble Space Telescope in March 2004 found nothing, and subsequent measurements from the MMT telescope suggest a much shorter rotation period of about 10 hours; rather typical for a body of its size.

Read more about this topic:  90377 Sedna

Famous quotes containing the words orbit and, orbit and/or rotation:

    Words can have no single fixed meaning. Like wayward electrons, they can spin away from their initial orbit and enter a wider magnetic field. No one owns them or has a proprietary right to dictate how they will be used.
    David Lehman (b. 1948)

    The human spirit is itself the most wonderful fairy tale that can possibly be. What a magnificent world lies enclosed within our bosoms! No solar orbit hems it in, the inexhaustible wealth of the total visible creation is outweighed by its riches!
    —E.T.A.W. (Ernst Theodor Amadeus Wilhelm)

    The lazy manage to keep up with the earth’s rotation just as well as the industrious.
    Mason Cooley (b. 1927)