A star, similar to our sun in size and composition, located about 12,000 light-years from Earth has swallowed up its jupiter-sized planet. This week’s quiz is about stars.
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What are stars made of?
- Radon
- Plutonium
- Tungsten and mercury
- Hydrogen and helium
Stars are big exploding balls of gas, mostly made of hydrogen and helium. Our Sun actually consists of 90% hydrogen and a mixture of other gases.
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What type of reaction power stars?
- Nuclear fusion
- Nuclear fission
- Combustion reaction
- Redox reaction
Deep inside a star’s core, hydrogen atoms smash together, forming helium and releasing huge amounts of heat and light energy. This is called nuclear fusion.
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What happens when a star becomes a red giant?
- The star’s atmosphere shrinks
- The star’s atmosphere begins to expand
- The star extinguishes
- Nuclear fusion stops in the star’s core
A low-mass star’s atmosphere starts to expand until it becomes a subgiant or giant star while fusion converts helium into carbon in the core.
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What is the heaviest element produced by a star?
- Helium
- Iron
- Gold
- Nickel
After the hydrogen in a star’s core is exhausted, it starts to fuse helium to form progressively heavier elements, carbon and oxygen and so on, until iron is formed.
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What colour do the hottest stars appear to be?
- Red
- Yellow
- Blue
- White
The hottest star appears to be blue as blue light carries more energy than red, which means it needs a hotter radiation source to produce it. The high temperature of blue stars, coupled with their high luminosity, means that they’re constantly blasting out huge amounts of energy into space.
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