The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Gaia-4b is considered a super-Jupiter planet, a relatively cold gas giant, orbiting its star over 570 Earth-days. That star ...

Astronomers have discovered an Earth-size planet that is showered with so much radiation, its atmosphere eroded away long ago ...

Here’s how it works. A planet-size object that possibly once visited the solar system may have permanently changed our cosmic neighborhood by warping the orbits of the four outer planets ...