what does it look like?
It is a large planetoid, surface is redd.
Introduction
90377 Sedna, or simply Sedna, is a large planetoid in the outer reaches of the Solar System that was, , at a distance of about from the Sun, about three times as far as Neptune. Spectroscopy has revealed that Sedna's surface composition is similar to those of some other trans-Neptunian objects, being largely a mixture of water, methane, and nitrogen ices with tholins. Its surface is one of the reddest among Solar System objects. It is a possible dwarf planet. Sedna is approximately tied with and as the largest planetoid not known to have a moon.

For most of its orbit, it is even farther from the Sun than at present, with its aphelion estimated at 937 AU (31 times Neptune's distance, or about 1.5% of a light-year), making it one of the most distant-known objects in the Solar System other than long-period comets.

where is sedna located in the solar system In the outer reaches of the Solar System. who discovered it? Michael Brown (Caltech), Chad Trujillo (Gemini Observatory), and David Rabinowitz (Yale University). who gave it it's name? Michael Brown.
It has a V-band absolute magnitude (H) of about 1.8, and it is estimated to have an albedo of about 0.32; it was the intrinsically brightest object found in the Solar System. It is one of the reddest objects in the Solar System, nearly as red as Mars. It has a V-band absolute magnitude (H) of about 1.8, and it is estimated to have an albedo of about 0.32, thus giving it a diameter of approximately 1,000 km.
90377 Sedna 90377 Sedna 90377 Sedna
Physical characteristics Physical characteristics Physical characteristics
Sedna has a V-band absolute magnitude (H) of about 1.8, and it is estimated to have an albedo of about 0.32, thus giving it a diameter of approximately 1,000 km. At the time of its discovery it was the intrinsically brightest object found in the Solar System since Pluto in 1930. In 2004, the discoverers placed an upper limit of 1,800 km on its diameter, but by 2007 this was revised downward to less than 1,600 km after observation by the Spitzer Space Telescope. Observations from the SMARTS telescope show that in visible light Sedna is one of the reddest objects in the Solar System, nearly as red as Mars. Sedna has a V-band absolute magnitude (H) of about 1.8, and it is estimated to have an albedo of about 0.32, thus giving it a diameter of approximately 1,000 km
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90377 Sedna [SEP] Introduction
90377 Sedna, or simply Sedna, is a large planetoid in the outer reaches of the Solar System that was, , at a distance of about from the Sun, about three times as far as Neptune. Spectroscopy has revealed that Sedna's surface composition is similar to those of some other trans-Neptunian objects, being largely a mixture of water, methane, and nitrogen ices with tholins. Its surface is one of the reddest among Solar System objects. It is a possible dwarf planet. Sedna is approximately tied with and as the largest planetoid not known to have a moon. For most of its orbit, it is even farther from the Sun than at present, with its aphelion estimated at 937 AU (31 times Neptune's distance, or about 1.5% of a light-year), making it one of the most distant-known objects in the Solar System other than long-period comets.