Its discovery began with Sedna.

Sedna is a dwarf planet smaller than Pluto.

Scientists believe Sedna is in the gravitational pull of a large object, which could be this new planet — aka "Planet 9." (Video via Kurdistan Planetarium)

It has about 10 times the mass of Earth.

It's an average of 600 times farther from the sun than the Earth is and takes 20,000 years to orbit the sun once.

This video includes images from NASA.

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Cox Enterprises CEO Alex Taylor and AJC Publisher Andrew Morse were joined by AJC editors and Atlanta business react during the ribbon-cutting ceremony at the Atlanta Journal-Constitution in Midtown on Friday, January 24, 2025.
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Austin Walters died from an overdose in 2021 after taking a Xanax pill laced with fentanyl, his father said. A new law named after Austin and aimed at preventing deaths from fentanyl has resulted in its first convictions in Georgia, prosecutors said. (Family photo)

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