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Course: Big History Project > Unit 3
Lesson 2: Creation of Complex Elements | 3.1- ACTIVITY: Is It In There?
- ACTIVITY: Threshold Card — Threshold 3 New Chemical Elements
- WATCH: Threshold 3 — New Chemical Elements
- WATCH: What Did Stars Give Us?
- WATCH: Why Star Stuff Matters
- READ: The Evolving Star - Subrahmanyan Chandrasekhar: Graphic Biography
- READ: A Little Big History of Silver
- Quiz: Creation of Complex Elements
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WATCH: Threshold 3 — New Chemical Elements
Discover how the universe, once filled with just hydrogen and helium, evolved to contain a variety of elements. Learn how the death of massive stars, through a process called supernova, creates new elements, scattering them across the cosmos and setting the stage for complex life. Created by Big History Project.
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At2:16, you say that these explosions produce all of the elements of the periodic table. I thought the only naturally occurring elements were uranium and the elements lighter than uranium. Do these explosions produce elements heavier than uranium? If so, does it produce ALL of them mankind has yet discovered and maybe even those yet undiscovered?(11 votes)
I think that these explosions only produce elemants lighter than uranium.(2 votes)
I have read that at the center of most galaxies, there are black holes. From this video, I understand that most elements are created during a supernova. Is it possible that the Milky Way was originally giant megastar that supernovaed and created all the stars and planets in our galaxy?(5 votes)
probably not. the star in queton would have to be up to 1 million times bigger than our sun snd the largest star recorded is only 10000 times bigger(1 vote)
Is ti possible that there are more and heavier elements in other parts of the universe ?(4 votes)
I am asking this because there is no other topic that matches as elements but
How come there is elements like einsteinium or californium? WHAT TYPE OF ELEMENTS ARE THOSE!?(2 votes)- All the element with an atomic number greater than 92 (which is Uranium) can be classified as transuranic elements. There are other classifications in use that further subdivide the transuranics including the transactinides which contain the elements with an atomic number greater than 104. Here is a link to an interactive chart of the nuclides where you can get lots of information about all of the elements.
https://www-nds.iaea.org/relnsd/vcharthtml/VChartHTML.html(3 votes)
Why were´t all elements created at the same moment? A second after the Big Bang! Because the Big Bang created incredible temperatures, I think even higher then in supernova explosion.(2 votes)
There were no elements to fuse from. The initial temperatures had to cool off before matter could form. Then the universe went through a phase where matter and antimatter formed in about the same amounts, so they almost immediately annihilated each other. Eventually, a little bit of matter won out and finally started to form hadrons like protons and neutrons. As the universe continued to cool, it finally got to the point (after about three minutes) where atomic nuclei could form. As the protons were already hydrogen, this period allowed the fusion of deuterium, helium, and very small amounts of Lithium, Beryllium and Boron. This period only lasted about 15 minutes before the universe expanded past the point where it could sustain any further fusion.(4 votes)
From what I know, as soon as the star starts to fuse Iron(Fe), is when it goes supernova, right?(2 votes)
Yes, just seconds(or even milliseconds) after the star fuses Iron(Fe), the star runs out of energy, and the star goes boom!, which is a supernova.(2 votes)
- If the star collapses once it has used up it's Hydrogen fuel or Helium Fuel or Carbon Fuel...etc, how does that element exist in the star? Shouldn't of been all fused/burned?(2 votes)
- How much of each element fuses into the next?
Is it just a smaller percent, meaning there is lots of light elements (He/H) but less heavy ones, because only a fraction of the light elements turns a heavier element?(2 votes) - how does the star erupt(1 vote)
Why were stars dying at the very beginning of the multiverse? Wouldn't they have just been created/born?(0 votes)
2:16Video transcript
NARRATOR:
After threshold two, the Universe had lots of stars, but most of space was still
cold, dark, and mostly empty. The Universe
consisted almost entirely of two types of atomic matter,
hydrogen and helium. These were both light gases and one of them
was totally inert. Like a painter
with just two colors, one of which won't mix, it was impossible to make
anything very interesting. The Universe
needed more colors, more chemical elements. And that was the
work of threshold three. Making new elements meant fusing more protons
and neutrons together. To do that, you needed
very high temperatures which could only be found
inside massive stars that were aging or dying. Only they have the right Goldilocks conditions
for threshold three. Why? Well, large
stars have so much mass that they can create enormous
pressures and temperatures. Those temperatures
get cranked even higher when large stars
run out of hydrogen. When that happens,
fusion stops at the center and the star collapses
like a burst balloon. If the star was big enough,
the collapse is huge, creating such high temperatures
that helium nuclei can fuse into nuclei of carbon. When the star has
used up its helium, it collapses again
and the cycle starts over. The star heats up and starts to fuse carbon
to form oxygen. It collapses again, then does the same
to create other elements like silicon, nitrogen,
and eventually iron. If it's a really,
really big star, it will finally die
in what's called a supernova. That's an explosion so hot
and so energetic that for a while, it'll shine
like an entire galaxy and will produce enough heat
to form all the other elements of the periodic table. Then the supernova scatters
these new elements into space and voila, we have a Universe
with lots of different elements. Threshold three was
crossed for the first time when the first large star died and it's still
being crossed today as billions upon billions
of large stars die, scattering the raw
materials needed to build wondrous
new forms of complexity.