Let’s go through each blank step by step, using what we know about how the solar system formed.
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1. Our Solar system started as a
cloud of gas and dust. A nebula is a cloud of
gas and
dust.
→ Nebulas are huge clouds in space made mostly of hydrogen gas and tiny bits of solid material (dust).
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2. It began to
collapse because of
gravity, the colliding particles caused it to heat up.
→ Gravity pulls everything together. When the cloud got dense enough, gravity made it shrink — that’s called collapsing. As particles bumped into each other during collapse, they heated up.
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3. As the nebula
spun faster, it started to flatten.
→ Just like when you spin pizza dough and it flattens out, spinning makes things spread sideways and flatten into a disk.
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4. As the nebula
continued spinning, the “spinning/force” is trying to throw everything
outward, while gravity is trying to pull everything
inward. These forces cause the nebula to form a
disk.
→ Spinning creates an outward push (like being pushed against the wall on a merry-go-round), but gravity pulls inward. The balance between these two forms a flat rotating disk.
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5. The more a
region becomes shaped like a
sphere, in the center of the nebula the
density is starting to rise. In the flattened outer areas the
material will eventually form
planets.
→ In the very center, where most mass collects, it gets super dense and hot — that becomes the Sun. Around the edges, clumps of material stick together to become planets.
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6. Soon the center gets so hot that it starts
nuclear fusion. It is now officially the
Sun. Near the Sun, only
rocky and
metallic materials can stay. (It’s too hot for atoms to slow down and stick together.)
→ Fusion = when atoms smash together and release energy — that’s what powers stars. Close to the Sun, it’s too hot for ice or gas to stick around — only rocks and metals survive.
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7. In the outer solar system where it is
colder, the gases and ices can
stick together.
→ Farther from the Sun, it’s cold enough for water, methane, ammonia, etc., to freeze and help build bigger objects — which become gas giants and icy moons.
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8. As the solar system continues to
cool, rocky material and metals near the sun can form into
terrestrial planets.
→ Earth, Mars, Venus, Mercury — these are rocky planets close to the Sun.
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9. Finally the outer solar system gets so
cold that the gases and chars [probably meant “chars” → “ices”] form
gas giants and ice giants.
→ Jupiter, Saturn (gas giants) and Uranus, Neptune (ice giants) formed far away where it was cold enough for gases and ices to gather in huge amounts.
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Final Answer:
1. cloud, gas, dust
2. collapse, gravity
3. spun faster
4. continued spinning, outward, inward, disk
5. region, sphere, density, material, planets
6. nuclear fusion, Sun, rocky, metallic
7. colder, stick together
8. cool, terrestrial planets
9. cold, gas giants and ice giants
Parent Tip: Review the logic above to help your child master the concept of formation of the solar system worksheet answers.
