Worksheet for learning about the formation of the solar system using a NASA video.

It looks like you've uploaded a worksheet titled "Video Notes: How did the solar system form?" from NASA Space Place. The task is to complete the blanks in the worksheet based on the content of the video. Since I can't view images directly, I’ll help you solve and explain each question based on standard scientific knowledge about the formation of the solar system (which aligns with what NASA's educational materials typically cover).

Let’s go through each blank one by one and fill it in with correct information, followed by explanations.

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1. The solar system is thought to have begun about ________ billion years ago.

✔ Answer: 4.6

📌 Explanation: Scientists believe the solar system formed approximately 4.6 billion years ago, based on radiometric dating of meteorites and Moon rocks.

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2. The solar system began in a part of a cloud of gas and dust called a ________.

✔ Answer: nebula

📌 Explanation: The solar system originated from a large cloud of gas and dust known as a nebula—specifically, a molecular cloud or solar nebula. This cloud collapsed under its own gravity, starting the process of star and planet formation.

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3. Perhaps due to a wave of pressure caused nearby exploding star(s) (phenomenon), the cloud began to compress and ________ in on itself.

✔ Answer: contract

📌 Explanation: A shockwave from a nearby supernova explosion could have triggered the collapse of the nebula. As the cloud compressed, it started to contract inward due to gravitational forces.

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4. The collapsing cloud rotated faster because of the conservation of ________, of material surrounding the center of the disk, the pressure became so high that the ________ began to fuse hydrogen atoms and nuclear fusion began.

✔ Answer: angular momentum; core / protostar

📌 Explanation:
- As the cloud collapsed, it spun faster due to the conservation of angular momentum (like a spinning ice skater pulling in their arms).
- In the dense central region, temperature and pressure rose until hydrogen nuclei fused into helium—this marks the birth of a star.
- The core (or protostar) eventually became hot enough for nuclear fusion to begin, forming our Sun.

So the full sentence:
> "...rotated faster because of the conservation of angular momentum, of material surrounding the center of the disk, the pressure became so high that the core began to fuse hydrogen atoms and nuclear fusion began."

Note: Some versions might say “protostar” instead of “core,” but both are acceptable depending on context.

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5. The ________ contains 99% of all material in our solar system.

✔ Answer: Sun

📌 Explanation: The Sun makes up about 99.8% of the total mass of the solar system. Everything else—planets, moons, asteroids, comets—is just a tiny fraction.

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6. Some of the leftover material clumped together due to gravity. Eventually, objects such as the planets and moons were built up through a process known as ________. These are the planet- and dwarf-planet-sized objects.

✔ Answer: accretion

📌 Explanation: Accretion is the process where small particles collide and stick together, gradually building larger bodies like planetesimals, then protoplanets, and finally planets and moons.

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7. The Earth and other ________ planets, formed near the sun, because they were made of rock and metal.

✔ Answer: terrestrial

📌 Explanation: The terrestrial planets (Mercury, Venus, Earth, Mars) are rocky and dense, located close to the Sun. They formed from silicate rocks and metals that could withstand the high temperatures near the Sun.

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8. The ________ and ________ planets formed farther away—meaning cold, giant planets made of ________ and ________.

✔ Answer: Jovian; gas giants; hydrogen; helium

📌 Explanation:
- The Jovian planets (Jupiter, Saturn, Uranus, Neptune) are also called gas giants (though Uranus and Neptune are sometimes classified as "ice giants").
- They formed farther out where it was colder, allowing volatile compounds like hydrogen and helium to condense and accumulate.
- So, these planets are primarily made of hydrogen and helium, with cores of rock and ice.

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9. The process took billions of years and formed the solar system as we see it today. The solar system has mostly cleared-out debris, but there are still leftover pieces called ________ in the asteroid belt and ________ in the outer reaches of our solar system.

✔ Answer: asteroids; comets

📌 Explanation:
- The asteroid belt between Mars and Jupiter contains remnants of planetesimals that never formed a planet.
- The outer solar system includes the Kuiper Belt and Oort Cloud, which contain icy bodies known as comets.
- These leftover materials are evidence of the early solar system.

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✔ Final Completed Worksheet:

1. The solar system is thought to have begun about 4.6 billion years ago.
2. The solar system began in a part of a cloud of gas and dust called a nebula.
3. Perhaps due to a wave of pressure caused nearby exploding star(s) (phenomenon), the cloud began to compress and contract in on itself.
4. The collapsing cloud rotated faster because of the conservation of angular momentum, of material surrounding the center of the disk, the pressure became so high that the core began to fuse hydrogen atoms and nuclear fusion began.
5. The Sun contains 99% of all material in our solar system.
6. Some of the leftover material clumped together due to gravity. Eventually, objects such as the planets and moons were built up through a process known as accretion. These are the planet- and dwarf-planet-sized objects.
7. The Earth and other terrestrial planets, formed near the sun, because they were made of rock and metal.
8. The Jovian and gas giants planets formed farther away—meaning cold, giant planets made of hydrogen and helium.
9. The process took billions of years and formed the solar system as we see it today. The solar system has mostly cleared-out debris, but there are still leftover pieces called asteroids in the asteroid belt and comets in the outer reaches of our solar system.

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Let me know if you'd like this formatted as a printable version or need help turning it into a study guide!