Asteroids

Asteroids

Middle School

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Learning Objectives

• Describe what asteroids are made of and where they came from.

• Explain where the asteroid belt is and how it may have formed.

• Tell the difference between asteroids, meteoroids, and meteors.

• Describe the orbits of asteroids and what Near-Earth Asteroids are.

Key Vocabulary

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Asteroid

A small, rocky body that orbits the Sun, often referred to as a minor planet or planetoid.

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Asteroid Belt

A region between Mars and Jupiter where many asteroids are found orbiting the Sun in our solar system.

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NEO (Near-Earth Asteroid)

A Near-Earth asteroid is an asteroid whose orbital path ends up crossing the orbit of the Earth.

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Meteoroid

Broken pieces of asteroids and comets that can range in size from small dust to 10 meters.

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Meteor

The visible streak of light from a meteoroid burning up as it enters the Earth's atmosphere.

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What Are Asteroids?

• Asteroids are large, irregular chunks of rock and metal orbiting the Sun.

• Because of their orbit around the Sun, they are also called minor planets.

• They are leftover materials from the formation of our solar system.

• Their composition includes rock, metal, carbon, ice, and different types of silicates.

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Multiple Choice

According to the information presented, what are asteroids primarily made of?

• Mostly ice and gas, similar to comets.

• A molten core with a thick atmosphere.

• Rock, metal, ice, carbon, and silicates.

• Liquid water and organic life forms.

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The Asteroid Belt

• The asteroid belt is a region of space between Mars and Jupiter.

• This area contains a large number of asteroids of various sizes.

• Scientists theorize it is a planet that did not completely form.

• Jupiter's strong gravitational pull prevented the materials from combining into a planet.

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Multiple Choice

What is the scientific theory for why a planet did not form in the asteroid belt?

• There was not enough rocky material available.

• The asteroids are a recent addition to the solar system.

• Jupiter's strong gravity pulled the materials apart.

• The material was too hot to form a planet.

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Asteroid Orbits and NEOs

• Some asteroids have orbits that bring them closer to our planet.

• An asteroid’s orbit is usually more rounded than a comet's elliptical path.

• Near-Earth asteroids (NEOs) are asteroids that cross Earth's own orbital path.

• Scientists monitor large NEOs because of the potential for a collision with Earth.

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Multiple Choice

What is the key characteristic of a Near-Earth Asteroid (NEO)?

• It is always found within the asteroid belt.

• Its orbit crosses the orbital path of Earth.

• It has a very elliptical orbit, like a comet.

• It is a remnant of a planet that failed to form.

Notable Asteroids & Related Objects

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Ceres

• Ceres is the largest asteroid in the main asteroid belt.

• It is also classified by scientists as a dwarf planet.

• Its own gravity has pulled it into a round shape.

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Meteoroid

• A meteoroid is a broken piece of an asteroid or comet.

• These rock fragments float through space and vary greatly in size.

• They can be as small as a tiny dust particle.

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Meteor

• A meteor is the streak of light from a meteoroid.

• This happens when it enters and burns in Earth's atmosphere.

• Friction with the air causes the meteoroid to burn up.

Multiple Choice

What is the main difference between a meteoroid and a meteor?

• A meteoroid is made of rock, while a meteor is made of ice.

• A meteoroid is much larger than a meteor.

• A meteoroid is a dwarf planet, but a meteor is not.

• A meteoroid is in space, while a meteor is the light from it burning in the atmosphere.

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Common Misconceptions

Misconception	Correction
All asteroids are found in the asteroid belt.	Some asteroids have orbits that bring them much closer to Earth.
Asteroids are just small, round rocks.	Asteroids come in many sizes and are usually not round.
A meteor is a rock that hits the Earth.	A meteor is a streak of light from a burning meteoroid.
Asteroid and comet orbits are the same.	Asteroid orbits are more rounded, while comet orbits are more stretched out.

Multiple Choice

Based on their origin as leftover materials, what does the study of asteroids primarily help scientists understand?

• The reasons for the seasons on Earth.

• The composition and mechanics of the Sun's core.

• The origins of our Solar system.

• The formation of Earth's oceans and atmosphere.

Multiple Choice

How does the dwarf planet Ceres differ from most other asteroids found in the asteroid belt?

• It is the only asteroid that is made entirely of metal.

• It is large enough to be spherical but does not clear its orbit.

• It orbits the planet Mars instead of the Sun.

• It was formed much more recently than other asteroids.

Multiple Choice

A scientist tracks a celestial body with a nearly circular orbit located between Mars and Jupiter. It appears to be composed of rock and iron. What is the most probable classification for this object?

• A meteor entering Earth's atmosphere.

• An asteroid in the main asteroid belt.

• A Near-Earth Asteroid (NEO).

• A comet from the outer solar system.

Multiple Choice

If a large asteroid's orbit was changed, causing it to cross Earth's path, what would be the most immediate and significant concern for scientists?

• The object's chemical composition changing due to its new orbital path.

• The reclassification of the object from an asteroid to a comet.

• The object becoming a Near-Earth Asteroid (NEO) and the potential for a collision.

• The potential to mine the object for rare minerals.

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Summary

• Asteroids are rocky remnants from the formation of our solar system.

• Most asteroids are located in the asteroid belt between Mars and Jupiter.

• Some asteroids have orbits that cross Earth’s path and are called NEOs.

• The largest asteroid, Ceres, is also considered a dwarf planet.

• A meteoroid is a space rock; a meteor is the light from it burning up.

• We study asteroids to learn about our Solar system and find valuable resources.

Poll

On a scale of 1-4, how confident are you about the concepts covered in today's review?

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