Here are some things you might already know, and might not !

• The Sun in our solar system is a star.
• There are around 200 Billion stars in the Milky Way alone.
• The Lifespan of our own star, the sun, is around 10 billion years.

• There are around 2500 stars visible to the naked eye at any one time in the night sky!
• There are 88 official constellations which are recognized by the International Astronomical Union.
• Some constellations are only visible in the northern hemisphere, while others are only visible in the southern hemisphere.

• Constellations that are visible in both hemispheres may appear upside down in the southern hemisphere.
• A few constellations can be viewed all year long but most are seasonal and can only be viewed at certain times of the year.
• The sun is the only known star in our galaxy which is not part of a constellation.

• The universe is around 13.7 billion years old.
• The Orion Nebula is the closest star forming region to Earth, it lies 1,300 light years away and is thought to be around 25 light years across.
• Each galaxy contains billions of stars, our own Milky Way galaxy contains approximately 200 billion stars.

• The solar system is around 4.6 billion years old.
• Each galaxy contains billions of stars, our own Milky Way galaxy contains approximately 200 billion stars.
• There are eight major planets and over 100 moons in the solar system.

• The Voyager 1 spacecraft is the furthest man-made object in the solar system, it is around 11 billion miles (18 billion km) from the sun and is still sending data back to Earth.
• Many of the planets in the solar system are visible to the naked eye.
• Mercury, Venus, Earth and Mars are the small rocky planets. Jupiter, Saturn, Uranus and Neptune are the gas giants.
• The space station is a working laboratory orbiting 240 miles above Earth and is home to an international crew. Have you ever wondered what it would be like to live and work in space? Follow astronauts on the International Space Station in a series of videos as they explain their daily routines. Learn where they sleep, and how they eat, exercise, work and spend free time. Compare life in space with life on Earth.

Here are some astronomy words and definitions that will help you understand your night sky!

• ASTEROID – a rocky object in space that can be a few feet wide to several hundred miles wide. Most Solar System asteroids orbit in a belt between Mars and Jupiter.
  ASTRO – a prefix that means “star” in the Greek language.
  ASTRONAUT – a person who travels in space.
  ASTRONOMER – a scientist who makes observations and studies planets, stars, galaxies any anything else in space.
  ASTRONOMY – the study of everything that is or was in space beyond the Earth’s atmosphere. Astronomy is the oldest science, dating back thousands of years to when people noticed objects in the sky overhead and  watched how they moved.
  AURORA – a glow over the polar regions caused by the interaction between Earth’s magnetic field and charged particles from the Sun.
  BIG BANG THEORY – a theory that says that the universe began with a super-powerful explosion.
  BLACK HOLE – super dense invisible objects in outer space that form when a massive star collapses from its own gravity. Black holes have such an enormous amount of gravity that they consume everything, including light, that comes close to them.
  CELESTIAL BODY – an object that is located in outer space.
  COMET – a small frozen mass of gas, dust, and ice. Comets revolve around the Sun or pass  through the Solar System in elliptical orbit.
  CONSTELLATION – groups of stars in that people have imagined to represent various objects or mythical beings.
  CRATER – a hole formed by a meteorite hitting the surface of a planet or a moon.
  DARK MATTER – nonluminous (not emitting light or visible) material that cannot be seen in the sky. Dark matter is one of the most mysterious things in the universe. Scientists think that  dark matter occurs everywhere but they don’t yet know exactly what it is made of.
  ELLIPTICAL – shaped like an egg, but with equal ends.
  GALAXY – a huge collection of stars, nebulae, star clusters, and dust and gas that measures many light years across. A galaxy’s shape can be elliptical, spiral, or irregular.
  GALILEO GALILEI (1564-1642) – Italian mathematician, astronomer, and physicist. First  to use a telescope to  observe the skies.
  KILOMETER – 1,000 meters. A kilometer equals 0.6214 miles.
  LIGHT YEAR – the distance light can travel in one year, which is about 6,000,000,000,000
  (6 trillion) miles, or 9,500,000,000,000 kilometers.
  METEOR -a meteoroid that enters the Earth’s atmosphere, heats up, and looks like a brief streak of fire in the sky.
  METEOR SHOWER – what you might see when Earth passes through the tail of a very old comet. During a shower you might see between 30 – 80 meteors an hour. Two well-known major showers are the Perseid shower, which peaks on August 12, and the Geminid shower which peaks on December 13.
  METEORITE – a part of a meteor that does not burn up when it enters the Earth’s atmosphere but falls to the Earth’s surface.
  METEOROID – a piece of stone or metal that travels in space around the sun.
  MOON – one of a Earth’s natural satellites, generally no smaller than ten miles in diameter. There are more than fifty known moons in the Solar System, including Earth’s.
  NASA – The National Aeronautics and Space Administration. NASA is in charge of all space programs for the United States.
  NEBULA – (another name for embryonic star cloud) a cloud of dust and gas in space in which a star is born.
  NEUTRON STAR – a rapidly spinning, extremely dense star composed of mainly neutrons (parts of an atom)..  Neutron stars are the leftovers of a supernova. They are only about 10 miles across, but are very dense.
  OPTICAL TELESCOPE – a telescope that uses mirrors to reflect an image to the observer.
  ORBIT – the path followed by an object in space as it moves moves around another object.
  PLANET – an spherical object that orbits a central star. It’s diameter can vary but is usually between 1,000 and 100,000 miles.
  PULSAR – Pulsars are thought to be rapidly rotating neutron stars with very strong magnetic fields. Bursts of energy are detected on earth from a pulsar at spaced intervals of several seconds or less.
  QUASAR – Quasars are not stars. They are galaxies traveling away from us at tremendous speeds.
  RADIO TELESCOPE – a telescope that studies planets, star, galaxies and other astronomical objects by using the radio waves they emit. These waves are longer than light waves and need very large antennas or arrays of antennas to capture them.
  RADIO WAVE – electromagnetic radiation. Other types of electromagnetic radiation are heat, light, and X-rays.
  REFRACTOR – A telescope in which the main light gathering element is a lens, known as the objective, or object lens.
  REFLECTOR – A telescope in which the main light gathering element is a mirror.
  SATELLITE – an object revolving around a larger object. Satellites can be natural, such as moons, or they can be man-made objects sent into orbit around the earth.
  SHOOTING STAR – another name for a meteor.
  SOLAR – something having to do with the sun.
  SOLAR FLARE – a storm or eruption of hot gases on the sun.
  SOLAR SYSTEM – The sun and all the planets, and other objects that orbit around it.
  SOLAR WIND – streams of gas particles flowing out from the sun.
  SPACE PROBE – an unmanned research spacecraft sent into space.
  SPECTROSCOPE – an instrument that breaks up white light from a star into its different colors. This information is used to determine the surface temperature of the star which helps to determine its age.
  SPECTRUM – The colors you see when white light is split apart. The order of colors is : violet, blue, green, yellow, orange, and red. A rainbow is a natural spectrum.
  SPEED OF LIGHT – Light travels at 186,000 miles per second, or 299,792,458 meters per second. Albert Einstein predicted that nothing can go faster than the speed of light.
  SUNSPOT – a dark area on the sun’s surface that is cooler than the area around it.
  SUPERNOVA – a great explosion that gives off tremendous amounts of light at the end of a star’s life cycle. A supernova can become a neutron star or a black hole.
  UNIVERSE – the space that contains all of the matter and energy in existence.
  WHITE DWARF – the remains of an old star after it uses its energy. It is a small, faint, whitish star that is very dense.