Space has a knack for bending our sense of scale. The Moon feels close enough to touch—after all, we see its craters with ...

Visualize Earth growing as big as other planets and the dramatic effects on its environment. Tears flowed in S.F. courtroom ...

the Earth you walk on today might not be the same planet that was born 4.5 billion years ago. Many scientists believe that in its infancy, Earth collided with another world the size of Mars, and that ...

What do the clouds on Jupiter, dust storms on Mars and rainstorms on Titan all have in common? They look like they belong on Earth. As we venture through the universe, scientists are finding uncanny - ...

"The most convincing scenario is that most of the building blocks of Earth and Theia originated in the inner solar system.

Astronomers have discovered that "super-Earth" planets may exist on wider orbits than previously thought — and this implies these rocky, or "terrestrial," worlds are far more common than was suspected ...

Searching for life on other planets requires more than just measuring their distances from their stars. A future NASA ...

An international team has made a significant breakthrough in understanding the tectonic evolution of terrestrial planets.

Planetary size was determined pre-spacecraft by measuring the planet's angular diameter and its distance from Earth (in AU, later converted to terrestrial units after the AU was accurately measured ...