90377 Sedna

90377 Sedna is a large planetoid in the outer reaches of the Solar System. As of 2020, it was at a distance of about 85 astronomical units from the Sun. Sedna has an exceptionally long and elongated orbit, taking approximately 11,400 years to complete. Its surface is one of the reddest among Solar System objects.

About 90377 Sedna in brief

Summary 90377 Sedna90377 Sedna is a large planetoid in the outer reaches of the Solar System. As of 2020, it was at a distance of about 85 astronomical units from the Sun. Sedna has an exceptionally long and elongated orbit, taking approximately 11,400 years to complete and a distant point of closest approach to the Sun at 76 AU. Its surface is one of the reddest among Solar System objects. It is approximately tied with 2002 MS4 and 2002 AW197 as the largest planetoid not known to have a moon. The Minor Planet Center currently places Sedna in the scattered disc, a group of objects sent into highly elongated orbits by the gravitational influence of Neptune. The discovery formed part of a survey begun in 2001 with the Samuel Oschin telescope at Palomar Observatory near San Diego, California. It was discovered by Michael Brown, Chad Trujillo, and David Rabinowitz on 14 November 2003. The name Sedna was chosen by Brown partly because the Inuit were the closest polar culture to his home in Pasadena, and partly because it would be easily pronounceable. Brown also suggested that future objects discovered in the Sedna region should also be named after entities in Arctic mythologies. The International Astronomical Union’s MinorPlanet Center said that such an action was a violation of protocol, and that some members of the IAU might vote against it. No competing names were suggested and no objections were raised to the name, and it was officially accepted in September 2004. The English spelling of Sedna’s name is: \”Sedna\”, a name from Inuit mythology, and also considered that in similar cases of extraordinary interest, it might allow it to be numbered before they were officially announced.

It has also been nicknamed \”The Flying Dutchman\”, or \”Dutch\”, after a legendary ghost ship, because its slow movement had initially masked its presence from his team. Its perihelion is too large for it to have been scattered by a known planet, leading some astronomers to informally refer to it as the first known member of the inner Oort cloud. Others speculate that it might have been tugged into its current orbit by a passing star, perhaps one within the Sun’s birth cluster, or even that it was captured from another star system. Another hypothesis suggests that its orbit may be evidence for a largePlanet beyond the orbit of Neptune, or that it may have been captured from a star system that is not in our solar system. The object is the coldest, most distant place known in the solar System, so we feel it is appropriate to name it in honor of sedna, the Inuits’ goddess of the sea, who is thought to live at the bottom of the Arctic Ocean. The calculations showed that the object was moving along a distant highly eccentric orbit, at adistance of 90. 3 AU from theSun, which indicated that its distance was about 100 AU in 2003. Precovery images have later been found in images of the Palamar Digitized Sky Survey dating back to 25 September 1990.