Scientists have been receiving X-ray signals from the Helix Nebula for decades, but now they believe it may hide a horrifying ...

So in some sense, alien worlds were not first discovered in the 1990s or even the 1980s. It took nearly a century to fully ...

The relative quantities of volatile gases like methane and ethane can reveal key details about distant Kuiper Belt objects.

For the better part of a century, we believed there were nine planets in our solar system, with Pluto being the farthest from the sun. Since the discovery of more Pluto-sized dwarf planets, that ...

"We might have finally found the cause of a mystery that's lasted over 40 years," said researcher Sandino Estrada-Dorado.

Astronomers have discovered four planets that are just a fraction of the mass of Earth orbiting Barnard’s Star, which is 6 ...

A decades-old cosmic mystery may finally be solved. Scientists now suspect that the strange X-ray glow from a distant white ...

Astronomers have confirmed the existence of four planets orbiting a star less than 6 light-years away with help from some of ...

For over 40 years, astronomers have been puzzled by strange X-ray signals from the Helix Nebula’s white dwarf. Now, they may ...

Scientists already know that a planet must be in the “Goldilocks zone”—not too hot and not too cold—to have liquid water, a ...