Created by:

Profile Photo

Last updated:

April 30, 2022


Unlimited Duration


This course includes:

Unlimited Duration

Badge on Completion

Certificate of completion

Unlimited Duration


Stars can necessarily be observed only at a distance.

Comparing stars is a 16-hour free course that introduces the HertzsprungRussell diagram, an essential tool in understanding the nature of stars. You should have some understanding of the basic stellar properties of luminosity and temperature in order to get the most from the course.

Course learning outcomes

After studying this course, you should be able to:

  • Describe and comment on the main features of a Hertzsprung-Russell diagram of stars in general, and of stars in a cluster
  • Outline a broad model of stellar evolution based on the observed properties of large numbers of stars, and describe how stars of different initial mass might evolve
  • Describe the effects of interstellar material on starlight, and outline some of the processes by which such material might be a source of electromagnetic radiation.

Course Curriculum

  • Introduction 00:10:00
  • Learning outcomes 00:07:00
    • Constructing the H-R diagram 01:00:00
    • The main classes of stars 00:40:00
    • How can we explain the distribution of stars on the H-R diagram? 00:35:00
    • Stellar masses and stellar evolution 00:35:00
    • Star clusters and stellar evolution 00:30:00
    • Introduction 00:10:00
    • Interstellar space is not empty 00:30:00
    • The effect of interstellar gas 01:00:00
    • The effect of interstellar dust 00:40:00
    • Using stars to probe the interstellar medium 00:20:00
    • The H-R diagram 00:10:00
    • Stellar masses and stellar evolution 00:10:00
    • Star clusters and stellar evolution 00:05:00
    • Observing through the interstellar medium 00:10:00
    • Questions 00:40:00
    • Conclusion 00:03:00

About the instructor

4.8 4.8

Instructor Rating







Profile Photo
Open University UK