The smallest planet in our solar system is Mercury. The planet is about 1/3 of the width of Earth with a radius of 1,516 miles. Earth’s moon has a radius of just over 1,000 miles.

Astronomers using NASA's James Webb Space Telescope spotted TWA 7b, a Saturn-sized exoplanet around a nearby star ...

Scientists Found 6,000-Year-Old Human Remains. No Other People Share Their DNA.

As the closest planet to the Sun, Mercury is exposed to the star's enormous gravitational field. And it's really stressful.

Webb Telescope captures TWA 7 b, a Saturn-mass planet 50 AU from its star, proving its ability to directly image smaller ...

To get a glimpse of the “Swift Planet,” EarthSky suggests waiting for the sun to set before looking west for the planet ...

New research suggests that Mercury's crust is shifting and twisting in unexpected ways thanks to the force of the Sun.

Learn how a new discovery of a giant planet can help scientists refine their theories of how planets form.

Learn more about TWA 7 b, an exoplanet with the mass of Saturn that was captured by creating a fake eclipse.

So-called M dwarfs are the most common stars in the Milky Way. A research team has determined around which of them Earth-like ...

Astronomers have spotted a cosmic mismatch that has left them perplexed - a really big planet orbiting a really small star. The discovery defies current understanding of how planets form.