Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Life Cycle of Stars
Transcript of Life Cycle of Stars
Describe the difference between mass & weight
Identify our sun's mass & life cycle
Predict the life cycle of high and low mass stars
A star begins
as a nebulae
This heat is what makes the star shine!
A star is formed....
When a large amount of gas (mostly hydrogen) starts to collapse on itself due to gravitational attraction, the atoms collide with each other faster and faster until it heats up.
Eventually the gas becomes so hot that the atoms no longer bounce off of each other...but begin to violently smash into each other and bond to produce helium. As the matter condenses, it becomes a protostar.
It contines to condense and heat up. Eventually it reaches critical mass and nuclear fusion begins.
The heat released is like an atom bomb explosion!
Main Sequence Star
Once the star is formed, it becomes a main sequence star.
It then follows one of 3 different life cycles depending on its mass.
Sun-like stars (small mass) - up to 1.5 times the mass of the sun
Huge stars - 1.5 to 3 times the mass of the sun
Giant Stars - over 3 times the mass of the sun
Small Mass Stars
(up to 1.5 times the mass of our sun)
Large Mass Stars
(1.5 times the mass of our Sun and larger)
Stars will spend most of their life as
Main Sequence Stars
Mass & Weight
Mass - The amount of matter that
makes up an object
Weight - a unit of measure of gravitational force
Main sequence star
Stars will eventually begin to run out of fuel
Small mass stars can burn for billions of years.
The smaller the mass, the longer it will burn because it uses less fuel (think of a small car vs. a large SUV)
As a star begins to run out of fuel, it will expand and become larger. It is then known as a Red Giant
When our sun begins to run out of fuel, it will grow large enough to consume Mercury, Venus and Earth.
As the outer layers of the star begin to burn off,
it becomes a planetary nebula.
As the core continues to cool,
it becomes a white dwarf. This stage can last for tens or hundreds
of billions of years.
A white dwarf cools until it becomes a black dwarf, which emits no energy. Because the universe's oldest stars are only 10 billion to 20 billion years old there are no known black dwarfs—yet.
When High Mass Stars begin to lose
fuel, they begin to cool, expand and
become a Red Supergiant.
If the star is massive enough, the collapse will
trigger a violent reaction in a Super Nova
After the star becomes a Super Nova and explodes, the huge star no longer has nuclear fusion and collapses in on itself. It then becomes a neutron star. It is so dense that one sugar cube of a neutron star matter would weigh about 100 million tons on earth!
When a Giant Star explodes into a Super Nova, it collapses so completely that it literally disappears from the universe.
What is left behind is so dense, that nothing can escape it's gravitational pull...not even light! This is
a Black Hole
Hawking, Stephen (2007) A Brief History of Time - The Universe in a Nutshell. New York, New York. Bantam Dell.
National Geographic (2013) Neutron Stars - Incomprehensible Density. retrieved 10/11/13 from http://science.nationalgeographic.com/science/space/solar-system/neutron-stars.html
National Geographic (2013) . White Dwarfs - Aging Stars. retrieved 10/11/13 from http://science.nationalgeographic.com/science/space/universe/white-dwarfs-article.html
YouTube. Crab Supernova Explosion. Retrieved 10/10/13 from
By Brigid Edwards