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A Star is Born!. Hi, kids!. You will learn how stars are made . You will also learn how stars are your great – great – great – great – great –great – great –great –great – great – great great – great – great – great –great –great – great - great grandparents!. The Sun Song (classic version).
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A Star is Born! Hi, kids! You will learn how stars are made.You will also learn how stars are your great – great – great – great – great –great – great –great –great – great – great great – great – great – great –great –great – great - great grandparents! The Sun Song (classic version) The Sun Song (rock version)
All stars are “born” in nebulae. A nebula is an enormous cloud of hydrogen and helium gas in space. nebula
click to zoom in One of the “stars” in Orion is actually a nebula
nebula protostar Over time, the nebula’s own gravity makes the nebula come together into a ball, called a protostar
When hydrogen fuses into helium, it gives off light (photons). This is why stars shine! The pressure inside a protostar is so strong that hydrogen (H) fuses together to become helium (He) H H He H H
Fusion happens billions of times every second inside a star H H H H He He H H H H H H He He H H H H H H
Stars shine because of nuclear fusion! H H H H H H He H H He H H H H He H H He He He H H H H H H H H He H H H H H H He H H H H
Eventually, protostars give off enough light to be officially called stars Don’t forget – a star is just a big ball of gas! Our sun is just a big ball of gas
Most stars have a “buddy star” – pairs of stars are called binary star systems This imaginary center is called the “Barycenter” However, you wouldn’t be here without stars... X
Every atom in your bodywas made by a star! “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, and the carbon in our apple pies were all made in the interior of collapsing stars. We are made of starstuff” – Carl Sagan The atoms of everything in this room, this town, and this planet were created inside a star!
Stars make all the different elements:3 helium atoms fuse into 1 carbon atom He C He He
4 helium atoms fuse into 1 oxygen atom He He O He He
This star is now a called a “Red Giant” – “cool” stars are red This star has no more hydrogen in its center – only in its outer edge. This causes the star’s exterior to expand and cool. Eventually stars run out of their hydrogen fuel, from the center out
Oh no, the sun will blow up in 157, 787, 999, 999, 999, seconds ! (2,629,800,000,000,000 minutes) (43,830,000,000,000 hours) (1,826,250,000,000 days) (5,000,000,000 years) Assume 365.25 days per year Debug: in presentation mode, start countdown. Then escape from presentation mode. Then return to presentation mode. It will work
Mercury and Venus will be destroyed Is it getting hot in here or is it just me? E Help! V Our sun is currently a “Main Sequence” star – but will grow into a Red Giant! M
After all the fusion stops inside a red giant, the gases float away and onlythe core remains This leftover gas is called a “Planetary Nebula” This core is called a “White Dwarf”
The White Dwarf is the burned out core of the star – like a burnt piece of charcoal
Stars smaller than our sun never become red giants – they just fizzle out into white dwarfs Which eventually burns out completely into a Black Dwarf
Betelgeuse click to zoom in Stars much larger than our sun become enormous red giants
A super red giant has intense fusion in its core – and explodes into a supernova A supernova can be brighter than a million stars!
The last Supernova we observed without a telescope was in 1604. It was so bright you could see it in the day time! Example of a Supernova
The white dwarf inside asupernovacollapses into aneutron star neutron star
A neutron star inside the Puppis Supernova You’ll learn more about neutron stars soon…
Really bigneutron starscollapseinto black holes You’ll learn more about black holes soon too… That's all, folks!