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

Mars, Venus, Jupiter and Saturn should be visible to the naked eye, but with a telescope you can spot Neptune and Uranus.

Feb. 18 marks the 95th anniversary of the discovery of our outermost planet-not-planet. Here's what to know about the short ...

This may explain the strange properties of the orbits of our solar system's planets ... warped the orbits of many planets. More NASA, ESA, Caltech / ISTOCK / GETTY IMAGES PLUS "[T]he puzzle ...

Planet ‘parades’ are not uncommon. While occasionally spotting 4-5 planets is not unusual, sighting the alignment of all 7 ...

The crystal-clear images show ... data and simulation models have confirmed a new type of planet unlike anything found in the Solar System. This provides another piece of the puzzle to understand ...

The four planet-strong "planet parade" currently visible to the naked eye in the night sky for a short time after sunset will ...

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. The ...

Scientists believe that two asteroids might be fragments of long-lost "planetary embryos" from the early solar system.

Canadian astronomers have taken an extraordinary step in understanding how planets are born, using the James Webb Space ...

The solar system's biggest gas giant planet orbits an average of 484 million miles from the sun. The fourth planet from the sun, Mars, looks like a star but has a slightly ruddy hue. Mercury will ...