New evidence shows that, far beyond Pluto, there may exist a hypothetical planet referred to as Planet X or Planet Nine.

There are no confirmed exomoons, moons orbiting distant exoplanets in other solar systems. There are a few candidates, but ...

The National Aeronautics and Space Administration is, to put it bluntly, kind of a mess. This is not meant to disparage the ...

Astronomers are gathering evidence of a massive hidden planet lurking beyond Neptune. These endangered predators have finally ...

For years, scientists believed most mini-Neptunes were covered by vast oceans of molten rock—essentially entire planets made ...

Mars is about to receive a double dose of attention. This weekend, a pair of identical NASA satellites will launch together ...

The comet is the third interstellar object from deep space ever recorded to pass through Earth’s solar system.

NASA's first multiple-satellite mission to another planet will map Mars' magnetic field and atmosphere in 3D, laying the ...

Water isn't just delivered to planets by comets and asteroids — it can also be forged as worlds form, a new study finds.

ESCAPADE is overseen by the University of California Berkeley, who named the spacecraft’s onboard satellites Blue and Gold ...

As 3I/ATLAS races through our solar system, NASA and Harvard take unprecedented action to study its bizarre anti-tail and ...

Astronomers have discovered that aging stars may be devouring their closest giant planets as they swell into red giants.