Vocabulary
The star at the center of our solar system.
What is the Sun?
The Sun is mostly made of these two elements.
What are hydrogen and helium?
Chemical reactions are like a candle. Nuclear fusion is like __________.
What are stadium floodlights?
Fusion combines two __________ nuclei to form helium.
What are hydrogen nuclei?
Scientists use this tool to study light from the Sun.
What is a spectrometer?
A giant ball of hot gases that gives off light and heat.
What is a star?
The Sun contains this percentage of the solar system’s mass.
What is 99.8%?
The type of nuclear reaction that powers the Sun.
What is nuclear fusion?
Fusion creates this element that makes up ~25% of the Sun.
What is helium?
Each element leaves unique ones of these in a spectrum.
What are spectral lines?
The distance between two consecutive peaks (or troughs) of a wave.
What is wavelength?
The Sun is made entirely of this state of matter.
What is gas?
The Sun’s energy comes from fusion / fission.
What is fusion?
Fusion releases more or less energy than it takes to start?
What is more?
Spectra show that the Sun is mostly made of __________ and __________.
What are hydrogen and helium?
A display of the different components of a wave, spread out by wavelength or color.
What is a spectrum?
This force keeps the solar system together.
What is gravity?
The type of nuclear reaction that splits heavy nuclei.
What is nuclear fission?
Fusion is hard to start because the two protons do this.
What is repel each other?
What evidence shows us that the Sun is mostly made of gases, not solids or liquids?
What is its spectrum (showing absorption lines from gases)?
Indicate specific wavelengths of light absorbed by elements in a gas.
What are spectral lines?
Trace amounts of these are found in the Sun besides hydrogen and helium.
What are heavier elements (like carbon, oxygen, iron)?
The Sun’s core temperature is about this many degrees Celsius.
What is ~15 million °C?
Write the simplified fusion equation: H-3 + H-2 → __________ + __________ + energy.
What is helium nucleus + neutron + energy?
How do spectral lines act like a “fingerprint” for elements?
Each element absorbs light at specific wavelengths, leaving unique lines in the spectrum.