Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to form in ...

New high-contrast images from SPHERE show a stunning variety of debris disks shaped by collisions of tiny planet-building ...

The Sun is an incandescent but benevolent dictator. For billions of years, it’s kept our star system well organized through the influence of its powerful gravity. All the planets revolve around it on ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar system ...

When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might ...

Every year, Earth follows a familiar pattern of seasonal changes: As summer rolls around in the Northern Hemisphere, winter creeps in in the Southern Hemisphere, and vice versa. But do other planets ...

(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.) Curious Kids is a series for children of all ages. If you have a question you’d like ...

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