PLANETS: A planet in our solar system is a body that orbits the sun and has enough gravitational pull to be nearly spherical and to clear its neighbourhood of debris.
There are eight planets in our solar system. If a planet orbits a star other than the sun, it is called an exoplanet.
MOON: The moon is the Earth’s only natural satellite. The other planets in the solar system, with the exception of Mercury and Venus, also have moons. Jupiter and Saturn have more than 60 each.
DEEP SKY OBJECTS: Deep sky objects lie outside the solar system, nestled among the stars.
Nebulae (glowing clouds of gas and dust), star clusters, globular clusters (ancient and densely packed clusters of stars that exist in a halo around a galaxy’s core) and galaxies are known as deep sky objects. These are amazing things to look for.
With a few notable exceptions, all of the objects, except galaxies, are located within our own Milky Way galaxy. There are many external galaxies to our own, each a collection of stars, gas and dust bound together by gravity. Our own Milky Way galaxy contains several hundred billion stars.
METEORS: When small particles, known as meteoroids, collide with the Earth they pass through our atmosphere and vaporize.
This results in a streak of light known as a meteor or shooting star. The particles are typically the size of a grain of sand but may occasionally be larger. Those that make it through the atmosphere intact to land on Earth are called meteorites.
CONSTELLATIONS: Constellations are patterns of stars in the sky, historically named after objects, animals and mythological characters.
There are 88 constellations of which roughly two thirds can be seen from the UK.
STARS: Stars are spheres of gas that emit energy, including light, through nuclear processes.
ASTEROIDS: Small rocky or metallic bodies that orbit the Sun and mainly lie between the orbits of Mars and Jupiter.
Some do orbit outside of this zone and currently there are several thousand known to come in close proximity to the Earth.