The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

The formation of our solar system from a singular nebula raises an intriguing question: why did each planet develop with a ...

While the composition of gas and dust in a molecular cloud is fairly uniform, everything changes once a star begins to form.

15, 2025 — New observational data and simulation models have confirmed a new type of planet unlike ... could reshape our understanding of the Earth-Moon system and the broader solar system.

Simpson and Chen ran mathematical models looking at how differently sized Earth-like worlds would have affected the rest of ...

BS4 may be anywhere between 17 and 40 feet across, and will approach at about twice the distance between the Earth and moon.

A planet-size object that possibly once visited the solar system may have permanently changed our cosmic neighborhood by warping the orbits of the four outer planets, a new study suggests.

A U.S. scientist searching for a civilization across 7 Earth clones circling the red dwarf star TRAPPIST-1 says its own alien ...

On Feb. 24, from west to east, you can see Mercury, Saturn, Neptune, Venus, Uranus, Jupiter and Mars, all spanning 117.5°, ...