Harry Kroto 2004 Low Mass Stars If a Star has a mass of less then 4 stellar masses, then the Star...

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Harry Kroto 2004

Low Mass Stars

If a Star has a mass of less then 4 stellar masses, then the Star will become a Red Giant when it has used most of its Hydrogen in the process of nuclear fusion.

This Red Giant will lose its mass by gently ejecting its outer layers to form a Planetary Nebula.

There are between 20,000 and 50,000 Planetary Nebulae in our Galaxy alone. At the centre of a Planetary Nebula is a White Dwarf Star.

A White Dwarf is about the same size as the Earth, but a mass up to 1.4 stellar masses (this is called the Chandrasekhar limit) if the mass is above this the star will have a high enough energy to restart nuclear fusion.

Planetary Nebula – a star that has blown off its gas and dust shell

Harry Kroto 2004

Harry Kroto 2004

Birth of the Sun 5000 000 000 yrs ago

Harry Kroto 2004

Harry Kroto 2004

Now here after 5000 000 000 yrs

Harry Kroto 2004

Harry Kroto 2004

One day the world will blow up into a Red Giant

Harry Kroto 2004

In 5000 000 000 yrs!

Harry Kroto 2004

In and then collapse and slowly die away as a white dwarf

Harry Kroto 2004

Harry Kroto 2004

Queen Magazine

Harry Kroto 2004

Low Mass StarsIf a Star has a mass of less then 4 stellar masses, then the Star will become a Red Giant when it has used most of its Hydrogen in the process of nuclear fusion. This Red Giant will lose its mass by gently ejecting its outer layers to form a Planetary Nebula. There are between 20,000 and 50,000 Planetary Nebulae in our Galaxy alone. At the centre of a Planetary Nebula is a White Dwarf Star. A White Dwarf is about the same size as the Earth, but a mass up to 1.4 stellar masses (this is called the Chandrasekhar limit) if the mass is above this the star will have a high enough energy to restart nuclear fusion.

A red giant star with an infra red partner (Mike Jura UCLA)Harry Kroto 2004

The main processes in the Sun

Harry Kroto 2004

Queen Magazine

Harry Kroto 2004