Ch 28: Telescopes: Help and Review

About This Chapter

The Telescopes chapter of this Intro to Astronomy Help and Review course is the simplest way to master understanding telescopes. This chapter uses simple and fun videos that are about five minutes long, plus lesson quizzes and a chapter exam to ensure students learn the essentials of telescopes.

Who's it for?

Anyone who needs help learning or mastering introductory astronomy material will benefit from taking this course. There is no faster or easier way to learn introductory astronomy. Among those who would benefit are:

  • Students who have fallen behind in understanding astronomy
  • Students who struggle with learning disabilities or learning differences, including autism and ADHD
  • Students who prefer multiple ways of learning science (visual or auditory)
  • Students who have missed class time and need to catch up
  • Students who need an efficient way to learn about telescopes
  • Students who struggle to understand their teachers
  • Students who attend schools without extra science learning resources

How it works:

  • Find videos in our course that cover what you need to learn or review.
  • Press play and watch the video lesson.
  • Refer to the video transcripts to reinforce your learning.
  • Test your understanding of each lesson with short quizzes.
  • Verify you're ready by completing the telescopes chapter exam.

Why it works:

  • Study Efficiently: Skip what you know, review what you don't.
  • Retain What You Learn: Engaging animations and real-life examples make topics easy to grasp.
  • Be Ready on Test Day: Use the telescopes chapter exam to be prepared.
  • Get Extra Support: Ask our subject-matter experts any telescopes question. They're here to help!
  • Study With Flexibility: Watch videos on any web-ready device.

Students will review:

This chapter helps students review the concepts in a telescopes unit of a standard intro to astronomy course. Topics covered include:

  • Light sensors of eyes and cameras
  • Properties of a telescope
  • Categories of astronomical observation
  • Defining diffraction limit
  • Radio, reflecting and refracting telescopes
  • Telescopes and the electromagnetic spectrum
  • Invisible wavelengths telescopes vs. visible light telescopes
  • Astronomical observations and how they're affected by Earth's atmosphere

12 Lessons in Chapter 28: Telescopes: Help and Review
Test your knowledge with a 30-question chapter practice test
Telescopes: Powers & Limitations

1. Telescopes: Powers & Limitations

This lesson will discuss some limitations and three important powers of the telescope: the light gathering power, resolving power, and magnifying power.

Types of Telescopes: Radio, Reflecting & Refracting Telescopes

2. Types of Telescopes: Radio, Reflecting & Refracting Telescopes

Learn about the different types of telescopes that astronomers use: X-ray, radio, gamma ray, reflecting and refracting. Learn what the differences are between them and what different things they show us about the universe.

How Telescopes Form Images

3. How Telescopes Form Images

This lesson will explain to you the fundamental points of how images are formed in refracting and reflecting telescopes as well as why our eyes need telescopes to help us see distant objects.

How Telescopes Detect & Measure Light

4. How Telescopes Detect & Measure Light

This lesson will go over the numerous methods astronomers can use to detect and measure light, including photography, spectroscopy, photometry, and CCDs.

Refracting & Reflecting Telescopes: Key Concepts

5. Refracting & Reflecting Telescopes: Key Concepts

This lesson will discuss some key terms and concepts relating to the refracting and reflecting telescope: primary mirror/lens, eyepiece, focal length, focal point, chromatic aberration, and achromatic lens.

Different Kinds of Traditional Reflecting Telescopes

6. Different Kinds of Traditional Reflecting Telescopes

This lesson will discuss three major kinds of traditional reflecting telescopes and their major differences. These include the Newtonian, Cassegrain, and Schmidt-Cassegrain telescopes.

Major Forms of Telescope Mounts & Modern Mirrors

7. Major Forms of Telescope Mounts & Modern Mirrors

This lesson will discuss two major telescope mounts, the equatorial and altazimuth mount, as well as two modern kinds of telescope mirrors, the floppy and segmented mirrors.

Radio Telescopes & Interferometry

8. Radio Telescopes & Interferometry

This lesson will go over some key concepts related to radio astronomy. We'll cover what radio telescopes are, the basics of how they function, and what their disadvantages are compared to optical telescopes and how this is resolved.

Telescopes & the Electromagnetic Spectrum

9. Telescopes & the Electromagnetic Spectrum

This lesson will teach you about which forms of light can reach the ground and which cannot and how we overcome this problem. We'll go over the concept of seeing as well as why we send telescopes into space.

Telescopes & False Color Images

10. Telescopes & False Color Images

How do we 'see' invisible forms of light if they're invisible? What would happen if your eyes had the ability for X-ray vision here on Earth? This lesson will help answer these questions.

Factors That Hinder Astronomical Observations on Earth

11. Factors That Hinder Astronomical Observations on Earth

This lesson will discuss several important factors that affect the ability of someone using a telescope to see a celestial object clearly, including weather, dust, seeing, and light pollution.

Using Telescopes, Spectroscopes & Probes to Investigate the Universe

12. Using Telescopes, Spectroscopes & Probes to Investigate the Universe

Humans are explorers. It's exciting, but it also leads to great discoveries about the universe. Learn how we use telescopes, probes and spectroscopes to investigate the universe.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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