Though the dwarf planet Eris on the edge of the solar system is much denser than Pluto, the two frigid worlds are nearly exactly the same size, a new study finds. Astronomers accurately measured Eris' ...

If you’re in the “Pluto is a planet” crowd, then you might consider selling all your 9 th planet merchandise on eBay while you still can: astronomers have found that Eris is more massive than Pluto.

The frozen surface of the dwarf planet Eris looks a lot like that of its smaller neighbor Pluto, new research has found. Both frozen worlds are covered predominantly with nitrogen ice, a research team ...

Astronomers have accurately measured the diameter of the faraway dwarf planet Eris for the first time by catching it as it passed in front of a faint star. This event was seen at the end of 2010 by ...

PASADENA, Calif.–Die-hard Pluto fans still seeking redemption for their demoted planet have cause for despair this week. New data shows that the dwarf planet Eris is 27 percent more massive than Pluto ...

WASHINGTON (Reuters) - Dwarf planet Eris, similar in size to its better-known cosmic cousin Pluto, has remained an enigma since being discovered in 2005 lurking in the solar system's far reaches.

January 5, 2005, is an astronomical anniversary that is not really marked but should be. It saw the discovery of dwarf planet ...

This artist's impression shows the distant dwarf planet Eris. New observations have shown that Eris is smaller than previously thought and almost exactly the same size as Pluto. Eris is extremely ...

Alas, poor Pluto, the dissing just keeps on coming. Last year, the erstwhile ninth planet was demoted because astronomers had discovered a nearby object, now officially named Eris, that was larger in ...

Most of us grew up learning that there are nine planets in our solar system – Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. But one day, back in 2005, Pluto got the shaft. A ...

In November 2010, the distant dwarf planet Eris passed in front of a faint background star, an event called an occultation. These occurrences are very rare and difficult to observe as the dwarf planet ...

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