The shape of a planet's orbit is one of its fundamental properties, along with its size and distance from its host star.

With a sun more than 4.5 billion years old, our solar system is considered "middle-aged," and the pictures of what it might ...

When a mudflat crumbles on Earth, or an ice sheet splinters on one of Jupiter's moons (Europa), or an ancient lakebed breaks ...

It is being called a "planetary parade" as seven planets are expected to be seen in the Earth's night sky on Friday, ...

For example, you’ll need binoculars or a small telescope to see Uranus and Neptune—so, while the seven planets will be there, ...

A stunning planet parade is now visible in the night sky. A planet parade is when several of our solar system's planets are ...

The seven other planets in our solar system can be seen in the sky at once through Friday, forming a planet parade. But two ...

Another finding was how dramatically the planets varied in brightness over just three years. The team discovered that PDS 70 ...

There's plenty more planet mayhem to come throughout the week. Today, the Moon enters its first quarter, which many will know ...

After Friday's spectacle, a "planet parade" of this size won't appear in the night sky for several years, experts say.

On Feb. 28, seven planets—Mars, Jupiter, Uranus, Venus, Neptune, Mercury, and Saturn—will all grace the early evening sky.