Star

How it is used

A basic word in every part of astronomy. Astronomers describe a star by its brightness, colour, temperature, mass and age, and talk about how stars are born, live and die. In everyday English, 'stars' can mean any points of light in the night sky.

Example sentences

1. Betelgeuse is a cool red star, while Rigel in the same constellation is hot and blue-white.

2. On a clear night far from the city, you can see a few thousand stars with the naked eye.

Common collocations

• bright star
• star formation
• massive star
• Sun-like star
• the life cycle of a star

Related terms

• SunThe star at the centre of our solar system. Its gravity holds the planets in their orbits, and its light and heat make life on Earth possible.
• constellationA group of stars that forms a recognisable pattern in the sky, and the area of sky around it. Astronomers officially recognise 88 constellations.
• main sequenceThe long, stable stage of a star's life when it fuses hydrogen into helium in its core. On a chart of star brightness against temperature, these stars form a diagonal band.
• nuclear fusionA reaction in which light atomic nuclei, such as hydrogen, join to form heavier ones, such as helium, releasing a huge amount of energy. It powers the Sun and other stars.
• supernovaA huge stellar explosion that can briefly shine as brightly as a whole galaxy. It happens when a massive star collapses or when a white dwarf gains too much mass.

More terms: Stars & Stellar Evolution

• black hole
• nebula
• red giant
• white dwarf
• neutron star
• pulsar
• event horizon