Mercury, the solar system’s smallest planet and the one closest to the sun, hasn’t received as much love as its celestial ...

Add Yahoo as a preferred source to see more of our stories on Google. Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky ...

The solar system's smallest planet has gotten smaller still.

Add Yahoo as a preferred source to see more of our stories on Google. About 4.6 billion years ago, a celestial cloud collapsed, paving the way for our solar system to form. Then, a nebula with strong ...

Scientists studying a young system around a Sun-like star think exocomets could be ferrying water.

We all need some space sometimes—but it's harder to find than you might think. How far into our universe do we have to go to reach somewhere truly empty? Our first stop is the International Space ...

For the first time, NASA's TESS (Transiting Exoplanet Survey Satellite) mission has identified a planet orbiting a distant star thanks to its warping of space-time. Unlike the star-hugging transiting ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. After decades of ...

See more of our trusted coverage when you search. Prefer Newsweek on Google to see more of our trusted coverage when you search. Five new exoplanets have been discovered—each of them so young, they ...

Webb observations reveal how young stars gradually strip gas from planet-forming disks, setting a deadline for worlds trying to become gas giants.