Mercury is putting on a show for skywatchers in the evening sky after sunset. But how well do you know the planet Mercury? Here's some Mercury trivia to ponder while planet gazing.

Our solar system's planets vary greatly in size, composition, temperature, chemistry and geology. Here are some notable extreme facts about the planets that orbit our Sun.

Here's a look at our solar system, from the scorching surface of Venus to the home of the largest volcano.

IT has a surface temperature of minus 225 degrees Celsius and was once the ninth and most distant planet from the Sun. But how big is it? Here’s all you need to know… How big is Pluto? … ...

We have just entered a very favorable period for observing the so-called "elusive" planet Mercury. From now, until about May 13, you should be able to find it with not much difficulty. In 1965 ...

Read these 75 interesting and cool facts about Earth to learn more about our planet.