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Scientists: Most distant object in solar system found

In this artist's visualization, the planet-like object dubbed "Sedna" is so far away that the sun appears as only a bright star.

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(CNN) -- Scientists may have discovered the solar system's most distant object, more than three times farther away from Earth than Pluto.

"The sun appears so small from that distance that you could completely block it out with the head of a pin," said Dr. Mike Brown of the California Institute of Technology, who helped in the discovery.

The object -- about 8 billion miles (12.8 billion kilometers) from Earth -- has been given the provisional name of Sedna, after the Inuit goddess who created sea creatures of the Arctic.

Brown and his team of astronomers, using Caltech's Palomar Observatory, found Sedna in November as part of an ongoing three-year outer solar system project. Days later, the high power Spitzer Space Telescope focused on the object.

Initial details indicated Sedna to be made of ice and rock, with temperatures never rising above -400 degrees Fahrenheit (-240 degrees Celsius), according to researchers.

Sedna is likely the largest object to be found circling the sun since the discovery of Pluto in 1930. It is still smaller than the ninth planet, though, with a diameter of more than 1,000 miles (1,700 kilometers).

The finding has sparked debate over what constitutes a planet.

Many astronomers say Pluto, with a diameter of just under 1,500 miles (2,300 kilometers), is too small to be a termed a planet and is just one of many minor objects in the outer reaches of the solar system.

But those who argue Pluto is a planet are likely to push the assertion for Sedna to become the 10th planet in the solar system.

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