About This Chapter
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 about introductory astronomy. Among those who would benefit are:
- Students who have fallen behind in understanding the types and characteristics of galaxies
- 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 the characteristics of galaxies
- 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 Characteristics of Galaxies 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 Characteristics of Galaxies chapter exam to be prepared.
- Get Extra Support: Ask our subject-matter experts any question about the characteristics of galaxies. 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 galaxies unit of a standard introductory astronomy course. Topics covered include:
- The Hubble tuning fork
- Spiral galaxies
- Dark matter
- Black holes
1. Links in the Cosmic Distance Ladder
This lesson goes over the important basics regarding the cosmic distance ladder and primary, secondary, and tertiary indicators. It will also define standard candles and parallax.
2. The Distribution of Galaxy Properties Along the Hubble Tuning Fork
This lesson will explore Edwin Hubble's famous classification scheme. We'll go over the major morphological differences between the categories of galaxies and the differences within them.
3. Types of Spiral Galaxies
Spiral galaxies are classified into several different types, depending on the characteristics of certain parts of their galaxy. Specifically, this lesson will go over Hubble's classification scheme of spiral galaxies with a small nod to lenticular galaxies as well.
4. The Collision & Assembly of Galaxies
This lesson will talk about how the assembly and collision of galaxies is actually related, what starbursts are, what will happen to our own galaxy in four billion years, and why our galaxy is a galactic cannibal!
5. Measuring the Properties of Distant Galaxies
This lesson will go over a couple of methods astronomers use to find out the properties of a distant galaxy, namely, its distance away from us and its mass.
6. Characteristics of Stars' Orbits in the Galaxy
This lesson will explore the spherical component and disk of the galaxy to find out what orbital tendencies stars and star clusters have within each section of the Milky Way Galaxy.
7. What Are the Different Types of Galaxy Clusters?
This lesson will define five different types of clusters: rich, poor, irregular, regular, and superclusters. We'll also find out what voids are and what the Local Group is.
8. Hubble's Law & Hubble's Constant
This lesson will go over and define the Hubble Law and Hubble constant. We'll not only do a practice problem but also define conceptually what these two things mean to our cosmos.
9. Dark Matter & Gravitational Lensing
This lesson will describe what dark matter is, how much of a cluster of galaxies is made of it, where it's located, and how all of this is related to gravitational lensing.
10. What Are Quasars?
This lesson will go over the odd-sounding term quasar. You'll learn how the term appeared, the different kinds of quasars, and what they are actually believed to be.
11. What are Active Galactic Nuclei?
This lesson explores and defines active galaxies and active galactic nuclei. You'll learn how they relate to quasars and how big active galactic nuclei are thanks to the observations of the properties of light.
12. What Are Supermassive Black Holes?
This lesson will explain to you what a supermassive black hole is, where they're found, how large they are, how they likely formed, and what they emit into space.
13. Galaxy Collisions: Ring & Elliptical Galaxies
This lesson will discuss the collisions between galaxies and what happens to the stars within them. It will also cover what a ring galaxy is and how it forms, as well as where elliptical galaxies are most common.
14. Seyfert Galaxies & Double-Lobed Radio Galaxies
This lesson will cover two particular kinds of active galaxies called Seyfert galaxies and double-lobed radio galaxies and their peculiarities, such as hot spots and synchrotron radiation.
15. Active Galactic Nuclei & the Unified Model
This lesson will explain the unified model, a model developed by astronomers that tries to help explain how it is that supposedly different objects are really the same thing viewed from different angles.
16. Elliptical Galaxy: Definition & Examples
In this lesson, you will learn about one of the main types of galaxies found in the universe and how to identify elliptical galaxies based on their defining characteristics.
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Other chapters within the Intro to Astronomy: Help and Review course
- The History of Astronomy: Help and Review
- How Scientists Think and Work: Help and Review
- Matter, Energy, and Astronomy: Help and Review
- Light in Astronomy: Help and Review
- Newton's Laws in Astronomy: Help and Review
- Rotational Motion and Astronomy: Help and Review
- Orbits, Tides, and Gravity: Help and Review
- Relativity in Time and Space: Help and Review
- Conservation Laws in Astronomy: Help and Review
- Earth's Spheres and Astronomy: Help and Review
- The Earth, Sky, and Moon: Help and Review
- The Moon's Form and Phases: Help and Review
- The Atmosphere on Earth and Other Planets: Help and Review
- Influences on Climate: Help and Review
- The Sun and Energy: Help and Review
- Star Types and Significance: Help and Review
- Measurement of Star Qualities: Help and Review
- The Birth and Life of Stars: Help and Review
- Star Death and Stellar Remnants: Help and Review
- Formation of the Solar System: Help and Review
- Galaxies, Stars and Solar Systems
- Components of the Solar System: Help and Review
- Small Celestial Bodies in the Solar System: Help and Review
- The Milky Way Galaxy: Help and Review
- Life & the Universe: Help and Review
- Navigation and Timekeeping in Astronomy: Help and Review
- Telescopes: Help and Review