Educational worksheet on lunar eclipses and phases for science class.

It looks like you've uploaded a worksheet titled "Earth's Moon: Computing Eclipses" from Chapter 21, which focuses on understanding lunar and solar eclipses through diagrams and questions. Since I can't view images directly, I’ll help you solve the problems based on typical content found in such worksheets.

Let me walk you through what this worksheet likely contains and how to solve it step by step.

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Worksheet Overview

This worksheet typically includes:
- Diagrams of the Moon’s phases.
- Questions about when solar and lunar eclipses occur.
- A diagram showing the alignment of the Sun, Earth, and Moon during eclipses.

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Step 1: Understanding the Diagrams

The top row of circles likely shows phases of the Moon, with labels or instructions to identify which phase is shown.

#### Common Moon Phases:
- New Moon (dark side facing Earth)
- Waxing Crescent
- First Quarter
- Waxing Gibbous
- Full Moon
- Waning Gibbous
- Last Quarter
- Waning Crescent

> Note: A lunar eclipse occurs only during a Full Moon, when Earth is between the Sun and Moon, casting a shadow on the Moon.

> A solar eclipse occurs only during a New Moon, when the Moon is between the Sun and Earth, blocking sunlight.

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Step 2: Answering the Questions

Here are typical questions and their explanations:

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#### Question 1: What causes the Earth’s shadow to fall on the Moon?
✔ Answer: A lunar eclipse occurs when the Earth blocks sunlight from reaching the Moon. This happens when the Sun, Earth, and Moon are aligned in a straight line, with Earth in the middle.

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#### Question 2: When does a lunar eclipse occur?
✔ Answer: A lunar eclipse occurs during a Full Moon, when the Moon passes through Earth’s shadow.

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#### Question 3: Why don’t we have an eclipse every month?
✔ Answer: The Moon’s orbit is tilted about 5 degrees relative to Earth’s orbit around the Sun. So, most of the time, the Moon passes above or below Earth’s shadow (during Full Moon) or doesn’t block the Sun (during New Moon). Only when the alignment is perfect do we get an eclipse.

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#### Question 4: What is the difference between a total and partial lunar eclipse?
✔ Answer:
- Total lunar eclipse: The entire Moon passes through Earth’s umbra (darkest part of the shadow).
- Partial lunar eclipse: Only part of the Moon enters the umbra.

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#### Question 5: What is a solar eclipse?
✔ Answer: A solar eclipse occurs when the Moon passes between the Sun and Earth, blocking all or part of the Sun’s light. It happens during a New Moon.

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#### Question 6: Why does a solar eclipse last longer than a lunar eclipse?
✘ Wait — actually, this is a common misconception.

✔ Correct Answer: A lunar eclipse often lasts longer than a solar eclipse because:
- Earth’s shadow is much larger than the Moon’s.
- The Moon moves slowly through Earth’s shadow.
- A total lunar eclipse can last up to 1 hour 40 minutes, while a total solar eclipse lasts only a few minutes at any one location.

So, if the question says "Why does a solar eclipse last longer?" — that would be incorrect. But if it asks why a lunar eclipse lasts longer, then the answer is:

> A lunar eclipse lasts longer because the Earth’s shadow is large and the Moon moves slowly through it, whereas the Moon’s shadow is small and moves quickly across Earth’s surface.

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Final Tips for Completing the Worksheet

1. Label the phases correctly using the diagrams.
2. Identify eclipse types based on alignment:
- Lunar eclipse: Full Moon + Earth in middle.
- Solar eclipse: New Moon + Moon in middle.
3. Use correct terminology: umbra, penumbra, totality, etc.

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If you can describe the specific diagrams or questions in your worksheet (e.g., “There are 8 moon phases shown”), I can give you exact answers tailored to your image.

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