The Solar System is home to a remarkable range of planets, from tiny rocky worlds to massive gas giants. But just how big are ...

A new trans-Neptunian object, 2017 OF201, has been found with a vast orbit and potential dwarf planet size. The finding hints ...

But just think about the planet compared to our own: If the solid core took up half of Mercury’s core’s radius, that’s around 1,000 kilometers, according to calculations in the paper—over ...

ALMA Measures Size of Seeds of PlanetsResearchers using the Atacama Large Millimeter/submillimeter Array (ALMA) have, for the first time, achieved a precise size measurement of small dust ...

Bus-size asteroid races towards Earth today. Will it pass by or endanger our planet? The newly discovered space rock, named ...

The recent discovery of a planet with rings larger than those of Saturn is a game-changer in our understanding of celestial bodies and their properties. This new finding not only expands the horizons ...

Asteroid 2025 QV5, which was first spotted in late August, will make a close approach to Earth on Wednesday (Sept. 3). It ...

Pluto is 100 miles smaller than the smallest planet but is not a major planet. Here's which planet in our solar system takes the title instead.

Space.com: Scientists say they have confirmed that a so-called 10th planet discovered last year is bigger than Pluto, but that likely won’t quell the debate over what makes a planet.

"Marsquake" data collected by NASA's InSight lander have revealed dozens of mysterious blobs within the Red Planet's mantle.