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What is the Sun?

03/02/201728/01/2017 What is

The Sun is a star in our Milky Way

The Sun gives off energy as electromagnetic radiation. That includes light, infra-red energy (heat), ultraviolet light and radio waves. It also gives off a stream of particles, which reaches Earth as solar wind. The source of all this energy is the reaction in the star which turns hydrogen into helium and makes huge amounts of energy.

The Sun gives off energy as electromagnetic radiation. That includes light, infra-red energy (heat), ultraviolet light and radio waves. It also gives off a stream of particles, which reaches Earth as “solar wind”. The source of all this energy is the reaction in the star which turns hydrogen into helium and makes huge amounts of energy.

The Sun is a star like many others in our Milky Way galaxy. It has existed for a little over 4.5 billion years, and is going to continue for at least as long. The Sun is about a hundred times as wide as the Earth. It has a mass of 1.9891×1030 kg, which is 333,000 times the mass of the Earth. The Earth can also fit inside the Sun 1.3 million times.

Source: Wikipedia

What is Andromeda Galaxy?

01/01/201727/12/2016 What is

The Andromeda Galaxy is the nearest spiral galaxy to the Milky Way, our galaxy

The Andromeda Galaxy is the nearest spiral galaxy to the Milky Way, our galaxy. Andromeda is sometimes called M31 or NGC 224 by astronomers. It is about 2.6 million light years away from us.

Andromeda is the largest galaxy of the Local Group, which consists of the Andromeda Galaxy, the Milky Way Galaxy, the Triangulum Galaxy, and about 30 other smaller galaxies.

At an apparent magnitude of 3.4, the Andromeda Galaxy is notable for being one of the brightest Messier objects, making it visible to the naked eye on moonless nights even when viewed from areas with moderate light pollution. Although it appears more than six times as wide as the full Moon when photographed through a larger telescope, only the brighter central region is visible to the naked eye. Being both large and bright, it is one of the farthest objects that can be seen without a telescope or binoculars.

Source: Wikipedia

What is Ganymede?

30/12/201626/12/2016 What is

Ganymede is the largest moon of Jupiter

Ganymede is the largest moon of Jupiter. It is also the largest moon in the Solar System. Ganymede is larger in diameter than Mercury, but has only about half its mass. Ganymede is much less dense. Ganymede is part of a group called the Galilean Satellites. These also include Io, Europa and Callisto.

Galileo Galilei discovered this moon in 1610. Simon Marius suggested the name Ganymede soon after. In Greek mythology, Ganymede was Zeus’ cup-bearer. Ganymede is the only Galilean moon of Jupiter named after a male figure.

Source: Wikipedia

What is Saturn?

27/12/201627/12/2016 What is

Saturn is the sixth planet from the Sun in the Solar System

Saturn is the second largest planet in the Solar System, after Jupiter. Saturn is a gas giant.

The thing that makes Saturn different is its very large system of rings around it. These rings are made of ice with smaller amounts of rocks and dust. Saturn also has 62 known moons orbiting the planet. The largest moon is Titan which is the second-largest moon in the Solar System. Saturn’s distance to the sun is about 1,400,000,000 km (869,000,000 mi). It takes Saturn 29.6 years to revolve around the Sun.

Saturn was named after the Roman god Saturnus.

Source: Wikipedia

What is Venus?

26/12/201627/12/2016 What is

Venus is the second planet from the sun

Venus is a terrestrial planet because it has a solid, rocky surface like other planets in the inner solar system. Astronomers have known Venus for thousands of years. Venus is the brightest thing in the night sky except for the Moon. It is sometimes called the morning star or the evening star as at some elongations it is easily seen just before the sun comes up in the morning and, at other elongations, just after the sun goes down in the evening. Venus comes closer to the Earth than any other planet does.

Venus is quite similar to earth in size and gravity. But Venus’ atmosphere (air) is mostly carbon dioxide with clouds of sulphuric acid which makes it very poisonous to humans.

The pressure on Venus’ surface is 92 times that of Earth. Venus has no moons. Venus spins very slowly on its axis and it spins in the opposite direction to the other planets. The ancient Romans named it after their goddess Venus.

Source: Wikipedia

What is Jupiter?

26/12/201627/12/2016 What is

Jupiter is the largest planet in the Solar System

Jupiter has the mass of about 318 Earths and it the largest planet in the Solar System. It is the fifth planet from the Sun. Jupiter is classified as a gas giant, both because it is so large and due to the fact that it is made up mostly of gas.

Jupiter is the third brightest object in the night sky and can be seen with the naked eye. Only the Earth’s moon and Venus are brighter.

Jupiter has at least 67 moons. Of these, 55 are very small and less than five kilometres wide. The four largest moons of Jupiter are Io, Europa, Ganymede, and Callisto. Ganymede is the largest moon in the Solar System.

Source: Wikipedia