A comet is a very small solar system body made mostly of ices mixed with smaller amounts of dust and rock. “Comet” comes from the Latin “cometes”, which in turn comes from the Greek “kometes”, meaning “long-haired”. A comet has four components: a nucleus, a coma, a dust tail and an ion tail. The nucleus … Read more
Asteroids are small Solar System bodies that orbit the Sun. Made of rock and metal, they can also contain organic compounds (some scientists suggest that asteroids could have brought they necessary chemicals to start life on Earth). There are millions of them, and they are often grouped by their composition. There are currently over 600,000 … Read more
The Milky Way Galaxy is our home galaxy in the Universe. It is a fairly typical barred spiral with four major arms in its disk, at least one spur, and a newly discovered outer arm. In one calculation, the Milky Way has a mass of about 100 billion solar masses, so it is easiest to … Read more
Pluto is the second closest dwarf planet to the Sun and from 1930 when it was discovered up until 2006, it was also considered the ninth planet of the solar system. Pluto is the largest dwarf planet but only the second most massive, with Eris being the most massive. The dwarf planet Pluto is named … Read more
Uranus, named after the the father of the Roman god Saturn, is the seventh planet in the Solar System and third of the gas giants. It is the third largest planet by diameter, yet fourth most massive. It’s not visible to the naked eye, and became the first planet discovered with the use of a … Read more
Neptune is the eighth planet from the Sun making it the most distant in the solar system. This gas giant planet may have formed much closer to the Sun in early solar system history before migrating to its present position. Due to its blue coloration, Neptune was named after the Roman god of the Sea. … Read more
Mercury is the closest planet to the Sun and due to its proximity it is not easily seen except during twilight. Mercury is only the second hottest planet.Despite being further from the Sun, Venus experiences higher temperatures. Being so close to the Sun, the daytime temperature on Mercury is scorching – reaching over 400 °C … Read more
Venus is the second planet from the Sun and is the second brightest object in the night sky after the Moon. Venus is also the closest planet to Earth. Named after the Roman goddess of love and beauty, Venus is the second largest terrestrial planet and is sometimes referred to as the Earth’s sister planet … Read more
Mars is the fourth planet from the Sun. The planet is named after Mars, the Roman god of war. It was known to the ancient Greeks as Ares, their god of war. This is thought to be because of the blood-red color of the planet which was also used by other ancient cultures. Chinese astronomers … Read more