Dedicated to PotterFreak_12
Astronomy Homework - Lesson One - The Life Of Stars
Word count: 675 words.
Quill: Quail feather quill.
Parchment: 1 roll.
Ink: Black ink.
(The word count does not include the words in or above these brackets)

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Stars in General -

Many people in their early life see stars as just tiny silvery-white flecks in the sky, but in reality, they are not tiny at all...nor are they silvery-white.

Although all are different sizes, masses and temperatures, the one quality they all share is what they are made up of - burning gas.

Sizes - With a huge range of sizes, on Earth, the stars are all compared to the Sun. 1.392 million kilometers in diameter and with a 696,000 kilometers radius, the Sun is the star that our planet orbits. Stars can range from being 450 times smaller that our Sun (with diameters about 3093 kilometers), all the way to being 1,000 times larger (with diameters about 1,000,392,000,000 kilometers).

Masses - With the Sun being 332945 times the mass of the Earth, other stars can range from a twentieth of that to over fifty times that.

Temperatures - Burning masses of boiling gas that started life in a Nebulae, stars are so hot that no one could ever even hope to get anywhere near one. The coolest average temperature being 3,000°C and the hottest average temperature being 50,000°C, stars are destined never to be touched. The temperatures of stars also determine their colour, the hottest being blue, and the coldest being red. Also, the hotter the surface temperature, the brighter the star.

Small Stars -

With nine stages of their lives, small stars can have a mass up to one and a half of that of the Sun.

Stage One - The star is born.

Stage Two - A part of the star will start to heat up and becomes a Protostar. If the Protostar has enough matter, the core temperature will reach 15,000,000°C.

Stage Three - When it reaches 15,000,000°C, hydrogen starts to form into helium.

Stage Four - The star stops contracting. It does this by releasing energy. It is now called a Main Sequence Star. The Sun is a Main Sequence Star.

Stage Five - The star remains as a Main Sequence Star until all of the hydrogen is converted into helium.

Stage Six - The core of the star starts to contract and reactions happen around the edges of it.

Stage Seven - The helium starts to form into carbon and the outer layers start to expand. It turns the star into a Red Giant.

Stage Eight - The helium runs out and the core begins to drift away.

Stage Nine - The core becomes a White Dwarf but, when it stops shining, it is deemed as dead and is then called a Black Dwarf.

Massive Stars -

With eight or (most commonly) nine stages of a massive star's life, they can range from anything from 3 times the mass of the Sun, to 50 times.

Stages One to Four are pretty much the same as the evolution of a small star.

Stage One - The star is born.

Stage Two - A part of the star will start to heat up and becomes a Protostar. If the Protostar has enough matter, the core temperature will reach 15,000,000°C.

Stage Three - When it reaches 15,000,000°C, hydrogen starts to form into helium.

Stage Four - The star stops contracting. It does this by releasing energy. It is now called a Main Sequence Star. The Sun is a Main Sequence Star.

Stage Five - Hydrogen becomes helium in just millions of years, instead of billions.

Stage Six - After all of the hydrogen has been converted into helium, the star becomes a Red Supergiant.

Stage Seven - During the course of the next million years, a load of nuclear reactions take place and, eventually, form shells around the iron core.

Stage Eight - Within the space of a second, a Supernova happens, the core collapsing in on itself. In that process, the outside layers are pushed away from the star.

Stage Nine - The core may survive the Supernova and, if it is or below three times the mass of the Sun, it will turn into a Neutron Star. Anything above three times the mass of the Sun and it will become a Black Hole.