The Universe Galaxies Stars Constellations Nebulae Black Holes Comets Asteroids Meteors

The universe is made up of many galaxies A Galaxy is a collection of stars, dust and gas held together by gravity. Earth is located in the Milky Way galaxy This is an image of the Milky Way Galaxy

There are many galaxies in the universe. The Andromeda galaxy is one of the closest to the Milky Way The Andromeda Galaxy

The Small Magellanic Cloud is a dwarf galaxy that is also close to the Milky Way

Some galaxies are close together, others are not. Galaxies are not all the same size or shape Trio of galaxies

There are four main shapes of Galaxies. 1. Spiral – The Milky Way and Andromeda galaxies are both spiral galaxies Spiral Galaxy

2. Lenticular – or disc shaped Lenticular Galaxy

3. Elliptical – or football shaped Elliptical Galaxy

4. Irregular – these galaxies have no distinctive shape. The Small Magellanic Cloud is an Irregular dwarf galaxy Irregular Galaxy

Stars A star is a huge, shining ball in space that produces a tremendous amount of light and other forms of energy. They appear as twinkling lights in the night sky. The sun and most other stars are made of gas and a hot, gas-like substance known as plasma

Stars are all different sizes and ages The Sun has a radius of 695500 km but is considered to be a dwarf star as many stars are larger than this.

The sun appears to be the biggest star because it is much closer to earth than any of the other stars Ring of fire on the surface of the sun

Stars are being born Birth of a star as captured by the Hubble Telescope

Stars are collapsing Dust from a collapsed star

Humans have looked up at the sky for thousands of years Humans have looked up at the sky for thousands of years. During this time patterns have been seen in the sky. These patterns are called constellations. Many constellations get their names from mythology. Different cultures named constellations differently. Many of the names we use today are from Greek mythology.

Astronomers of ancient civilizations grouped stars according to their shapes (of Gods, animals, or familiar objects). These groups of stars are called constellations. The most famous star group is the twelve groups of the zodiac. Constellations are important in the study of space. They form a map of the sky and any location in the sky can be described in relation to the position of a known constellation. Some well known constellations are on the following slides

Another feature of galaxies are Nebulae. A Nebula is a cloud of dust particles and gases in space. The Seagull Nebula

There are two types of nebulae. A diffuse Nebula A Planetary Nebula. The Wizard Nebula

Black Holes A Black hole is a region of space where matter is so dense that the gravitational force does not allow anything to escape it even light A double Black hole

Comets A comet is an icy body that releases gas or dust. Most of the comets that can be seen from Earth travel around the sun in long, oval orbits. McNaught Comet

Some comets, however, become visible to the unaided eye for several weeks as they pass close to the sun. Lulin Comet

Asteroids Asteroids are small planetary bodies that revolve around the sun. Asteroids are also called minor planets or planetoids. Most of them are in the asteroid belt between the orbits of Mars and Jupiter Asteroid

Meteor A meteor is a bright streak of light that appears briefly in the sky. Observers often call meteors shooting stars Meteor

A meteor appears when a particle or chunk of metallic or stony matter called a meteoroid enters the earth's atmosphere from outer space. The meteoroid heats up in the atmosphere so that it glows and creates a shining trail of gases and melted meteoroid particles. Most meteors glow for about a second. Meteor

Most meteoroids disintegrate before reaching the earth Most meteoroids disintegrate before reaching the earth. But some leave a trail that lasts several minutes. Meteoroids that reach the earth are called meteorites. Meteorite

Meteor showers occur at certain times each year Meteor showers occur at certain times each year. They are cause by stream of tiny meteoroids. At such times, the sky seems filled with a shower of sparks Meteor Shower