For the first time in years, astronomers are seriously talking about adding a new member to the solar system’s planetary ...

The historic Lowell Observatory announced this week that it will drastically reduce internally funded research and shrink its ...

Today, the dwarf planet Pluto orbits the sun from the edge of our solar system and its surface temperature is an inhospitable negative 378 to negative 396 degrees Fahrenheit. But a new study suggests ...

LONDON — The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper's authors have ...

Pluto may have been demoted to non-planet status, but it still commands a court of five moons, as is fitting for the king of darkness; after all, Pluto is the Roman equivalent of the Greek God Hades.

Nearly a century after Pluto’s discovery, astronomers are still searching for mysterious planets beyond Neptune - including a ...

Since Pluto's discovery in 1930, there have been nine planets in the solar system, but a year ago, scientists at the California Institute of Technology said there were ten. An object they called Xena ...

Your 1996 column on the mysterious giant Planet X some astronomers thought might lurk beyond Pluto is in need of an update. In particular, you should tell the story of the dwarf planet Eris, whose ...