Astronomers were finally able to catch a good look at Pluto's twin planet, the distant Eris and is one of the brightest objects in the solar system.

The new observations, published in the journal Nature, is the first time astronomers were able to probe Eris. Scientists have been unable to observe Eris because it is so far from the Earth. Eris is about three times farther from the sun than Pluto. However, despite being a speck in the night sky, Eris has disrupted the astronomy world since its discovery in 2005.

"It's very difficult, because it's so small in the sky," said lead author Bruno Sicardy, a planetary scientist at Pierre and Marie Curie University and Observatory in Paris.

Astronomers had to wait until Eris crossed over a star before they could measure the amount of starlight the dwarf planet blocked. The scientists were then able to calculate Eris' diameter which is about 1,445 miles.

When Eris was first discovered in 2005 in the region called the Kuiper Belt, astronomers were stunned. Pluto was thought as the smallest and farthest planet in the solar system. With the discovery of Eris, that assumption was tested. Astronomers began to question the existence of more objects the size of Pluto in the Kuiper belt.

And then there was the big decision to downgrade Pluto.

Astronomers believed that if there were more objects the size of Pluto and Eris, then could there be a new category to describe them? In 2006 the International Astronomical Union voted to downgrade Pluto from a full size planet to "dwarf planet". The new dwarf planet category also included Eris, the big asteroid Ceres and two other large Kuiper belt objects, Makemake and Haumea.

Eris has also managed to upstage Pluto by being one of the brightest objects in the solar system. The study's authors think Eris shine comes from a millimeter thick layer of methane and nitrogen frost coating the dwarf planet's surface.

Even though scientists have managed to get Eris' size down that still doesn't mean that Pluto will get back its planet status. Because Pluto's size isn't known precisely there's no way to tell if Eris is smaller or larger than Pluto. And even if Eris is smaller, Pluto will still be lumped together with other dwarf planets.

"Pluto is never going to go back to being a planet," said Amanda Gulbis, a planetary scientist at the South African Astronomical Observatory who was not involved in the study. "The definition has been set."