Nemesis (hypothetical Star) - Orbit of Sedna

Orbit of Sedna

The trans-Neptunian object Sedna has an extra-long and unusual elliptical orbit around the Sun, ranging between 76 and 975 AU. Sedna's orbit is estimated to last between 10.5 and 12 thousand years. Its discoverer, Michael Brown of Caltech, noted in a Discover magazine article that Sedna's location seemed to defy reasoning: "Sedna shouldn't be there," said Brown. "There's no way to put Sedna where it is. It never comes close enough to be affected by the Sun, but it never goes far enough away from the Sun to be affected by other stars." Brown therefore postulated that a massive unseen object may be responsible for Sedna's anomalous orbit.

Brown has stated that it is more likely that one or more non-companion stars, passing near the Sun billions of years ago, could have pulled Sedna out into its current orbit. In 2004, Kenyon forwarded this explanation after analysis of Sedna's orbital data and computer modeling of possible ancient non-companion star passes.

Read more about this topic:  Nemesis (hypothetical Star)

Famous quotes containing the words orbit of and/or orbit:

    The Fitchburg Railroad touches the pond about a hundred rods south of where I dwell. I usually go to the village along its causeway, and am, as it were, related to society by this link. The men on the freight trains, who go over the whole length of the road, bow to me as to an old acquaintance, they pass me so often, and apparently they take me for an employee; and so I am. I too would fain be a track-repairer somewhere in the orbit of the earth.
    Henry David Thoreau (1817–1862)

    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)