Stars are suns and the sun is a star. Stars only look small and faint because they are incredibly far away. The nearest star apart from the sun is Proxima Centauri and is just over 4 light years away. That means Proxima Centauri is so far away that it takes light over 4 years to reach the Solar System from there. The other stars are even further away.
Some stars are hotter than the sun. Those stars look blue in the sky. Other stars are cooler than the sun. They look red in the sky. Stars are incredibly hot and shine because Nuclear reactions in their cores keep heating them. When the nuclear fuel is exhausted some stars blow themselves up to form supernova. Other stars form black holes or white dwarf stars or pulsars. Astronomers may try to estimate how many stars there are in the Milky Way galaxy or the Universe.
Religion[]
In the Christian sacred scriptures Satan cast down a third of the stars of heaven with his tail as he fell to Earth (Revelation 12:4). Even if we assume this only means 1/3 of the stars visible to the naked eye, we're talking about 2000+ giant balls of superheated plasma, most of them hundreds of times bigger around than the Earth. This would have resulted in a mass-extinction event at least comparable to the small asteroid that struck the Yucatan peninsula 65 million years ago and wiped out the dinosaurs. In many religions, when the end of the world arrives the stars will fall from heaven.
Throughout the Bible, the authors are apparently ignorant of the relationship between the sun and the moon, and the fact that the sun is a star. The Bible incorrectly refers to the sky as a dome over the earth, with the stars, the sun, and the moon being fixed to the dome. We now know that the stars are an astronomical number of light years away, with the light of many of them being the only thing left for us to witness as they have since exploded, shooting gamma ray bursts that incinerate other unfortunate bodies around them. But these passages are only metaphorical of course.
Islam also gets astronomy quite wrong. Muhammad describes the sky as being made of seven layers, and he arbitrarily placed the stars in the lowest layer, lower than the moon. This is, of course, incorrect, if taken literally. He also assumed that the stars are just lamps to adorn the lower heaven that are also used as missiles to shoot the intruding evil spirits (jinns). Although stellar anti-genie missiles might sound pretty awesome, this hypothesis is provably incorrect: stars follow motions that are predictable and consistent. ("Shooting stars" aren't stars at all, but meteors.)
External links[]
- Hertzsprung-Russell Diagram This links the mass of a star and its age with its temperature and luminosity.
Videos[]
- Carl Sagan - Our Sun's Life Cycle Video about the sun and other stars.
- The Life Cycle of a Star Video about all stars including our sun
- HR Diagram - Stars Video explaining the different types of stars
- Ever Wonder How Elements are Formed ? Fusion and Beyond! Video explaining how elements form in stars and Supernovae
Incorporates material from Liberapedia and material deleted at RationalWiki.