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 ...

Small in comparison to the gas planets found further from the Sun, they also rotate at a more sedate pace and have few moons… Mars, one of the three rocky planets, is the fourth closest planet ...

Ever since NASA's New Horizons sent back the first-ever photos of Pluto in 2015, the dwarf planet's mysterious heart ... roughly the size of Arizona from north to south. Pluto was discovered ...

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 ...