Also found in: Dictionary, Acronyms, Wikipedia.


in astronomy, the most distant known large object in the solar system. With a highly eccentric elliptical orbit that ranges from an estimated 76 AU to 937 AU, Sedna also has an extremely long orbital period, estimated at 11,400 years. Although the dwarf planet ErisEris,
in astronomy, the largest known dwarf planet. Eris, whose highly eccentric elliptical orbit ranges from 38 AU to 97 AU and is inclined more than 44°, is the largest known object of the Kuiper belt (see comet), with a diameter (1,445 mi/2,317 km) slightly larger than
..... Click the link for more information.
 was later discovered at a more distant location, Sedna's orbit takes it much further from the sun. Its diameter is c.600 mi (1,000 km). Sedna, which appears almost as red as Mars, has a surface that is believed to be covered with tholins (a mix of hydrocarbons, formed from methane and nitrogen by ultraviolet light, which give Sedna its reddish appearance) as well as frozen methane and water.

It is unclear where Sedna was formed, or why its orbit is so elongated. It does not appear to be a Kuiper belt object, because its orbit never gets close to that region of space; some astronomers have suggested Sedna might be an inner Oort cloud object (see cometcomet
[Gr.,=longhaired], a small celestial body consisting mostly of dust and gases that moves in an elongated elliptical or nearly parabolic orbit around the sun or another star. Comets visible from the earth can be seen for periods ranging from a few days to several months.
..... Click the link for more information.
). Sedna was discovered on Nov. 14, 2003, by astronomers Mike Brown, Chad Trujillo, and David Rabinowitz, using computer analysis of images taken in a survey of the Kuiper belt. It was named for the Inuit goddess of the ocean because of the cold, remote location its orbit traverses. The term "sednoid" was coined to described bodies found between the Oort cloud and Kuiper belt; a second such planetoid was discovered in 2012.


A body orbiting the Sun far out beyond the planet Pluto at a mean distance of 90 AU. Its orbital period has been estimated at about 10 500 years. At the time of its discovery, made in November 2003 by a team led by Mike Brown from the California Institute of Technology, it was thought to be approaching perihelion, a point 76 AU from the Sun. A distinctive feature is its reddish color. Sedna takes its name from the Inuit goddess of the sea. It is believed to be an object made of ice and rock belonging to the inner Oort Cloud. With an estimated diameter of about 1800 km, Sedna is thought to be about halfway in size between Pluto and the Kuiper Belt object Quaoar. The temperature on Sedna is probably lower than 30 K.
Mentioned in ?
References in periodicals archive ?
They believe the outer crust of the missing object could be made of sticky organic particles left behind when the ice that traditionally forms a comet melts away and was captured by Sedna.
The modest inclinations of Sedna (12[degrees]) and 2012 [VP.
The enormous, stretched orbits of Sedna and 2012 VPU3 are unlike anything else in the solar system.
Sedna Hospital --bautizado como la diosa del mar de los inuit o esquimales-- es un conjunto arquitectonico "inteligente", equipado con tecnologia medica de vanguardia.
OH WHAT A YEAR: The planet Sedna is ranked higher than Scotland by FIFA, Beckham helps Vodafone's profits while Goram is a winner in love; FIRE STARTER: Fernando Ricksen was devastated to see Edinburgh's fireworks cancelled; NUMBERS GAME: Gazza; wanted to be called G8 while thankfully for Scotland's suffering fans Berti Vogts got his P45
The California team estimates that Sedna requires 10,500 Earth years to complete a single 84-billion-rnile orbit around the sun.
Sedna is believed to be between 800 miles and 1,100 miles across - about three quarters of the size of Pluto.
Sedna is believed to be about 1,250 miles wide but may even be larger than furthest-known planet Pluto.
for SEDNA Aircon powered by solar panels, Easy Link for Zero payment (changing of existing bulbs to LED), Barring Technologies for waste water treatment and Thehco Green Technology for green vehicles discussed their available technologies for MSMEs.
Another such object, 90377 Sedna, is likewise distantly adrift.
The newly found object joins the dwarf planet Sedna as one of only two worlds known to orbit beyond the Kuiper belt, where Pluto resides along with hordes of icy boulders left over from the solar system's formation.
En contraste, en la Ciudad de Mexico, la esposa del mandatario, Maria de Lourdes Salinas, es accionista mayoritaria de moderno complejo Sedna Hospital, especializado en atencion a la mujer.