With sapphire waterfalls, lava rain and orbits around dead stars, these distant worlds push the limits of what’s possible.

In a zesty new discovery, scientists have unearthed a strange lemon-shaped exoplanet. It is unlike one we have seen before, ...

Fresh orbital images and new geological analysis have revealed eight mysterious caves on Mars that appear unusually well suited to protect traces of life. Together, these caverns, portals and ...

Mars is often described as silent, barren, and still. But beneath its dusty surface and cold skies, something unusual has ...

Astronomers are investigating a strange class of exoplanets known as eccentric warm Jupiters — massive gas giants that orbit their stars in unexpected, elongated paths. Unlike their close-orbiting ...

A strange 200 million-year-old object with the mass of a planet has been discovered 20 light-years from Earth, outside our solar system. The "rogue," as it's referred to by researchers, is producing ...

Scientists measured mass and distance of free floating planet drifting through space without star for first time.

Scientists are scratching their heads over a recent James Webb Space Telescope (JWST) discovery that looks more like a piece of fruit than your typical celestial sphere. The planet, designated PSR ...

There may be a warp in the Kuiper Belt, possibly caused by “Planet Y” — a Mercury-to-Earth-sized world that orbits the sun way beyond the orbit of Neptune. Is there a mysterious “Planet Y” orbiting ...

A mysterious comet flying through our solar system may be doing more than just passing by—it could help explain how giant planets like Jupiter are born. At a major planetary science conference in ...

A mysterious "rogue" planet has been observed gobbling six billion tonnes of gas and dust a second -- an unprecedented rate that blurs the line between planets and stars, astronomers said Thursday.