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Admission requirements

Basic knowledge of atomic physics and quantum mechanics is required. When necessary, concepts of thermal and statistical physics will be discussed during the course.


All the light we see when we look up at the night sky comes either directly or indirectly from starlight. Understanding the physics of stars is therefore the basis of many aspects of astronomy: it is key to unravel the light of nearby and extremely distant galaxies. It also is an important factor in determining whether exo-planets can host life as we know it.

Course objectives

The main goal of this lecture series is to review the physical processes that determine the basic properties of stars. Topics that will be addressed include: nuclear energy production, energy and radiation transport, and the stellar structure equations. These will then be used to present models of the basic observable properties of stars such as mass, luminosity and surface temperature. These models also give a good understanding of the distribution of stars in the Hertzsprung-Russel diagram where for a collection of stars absolute magnitudes are plotted versus their observed colours. Also, we will review what happens when stars come at the end of their energy production. For massive stars we will study how supernova explosions lead to the formation of neutron stars and even black holes, while for less massive stars we will see that the final end products are white dwarfs. Finally, we will sketch some of the physical processes that lead to the formation of stars.

Soft skills

In this course, students will be trained in the following behaviour-oriented skills:

  • Problem solving (recognizing and analyzing problems, solution-oriented thinking)

  • Analytical skills (analytical thinking, abstraction, evidence)

  • Structured thinking (structure, modulated thinking, computational thinking, programming)

  • Written communication (writing skills, reporting, summarizing)

  • Critical thinking (asking questions, check assumptions)


See Schedules bachelor Astronomy

Mode of instruction

Lectures and seminars

Assessment method

  • Computer problems and class assignments: 30%. Only if the average grade is higher than 5.0, students are allowed to take the written exam.

  • Written exam: 70%. See Examination schedules bachelor Astronomy


Lecture notes, additional readings and assignments will be provided via Blackboard. To have access, you need an ULCN account. More information:

Reading list

  • LeBlanc, F. (2010): An Introduction to Stellar Astrophysics, ISBN: 978-0-470-69956-0 required


Register via uSis. More information about signing up for classes and exams can be found here. Exchange and Study Abroad students, please see the Prospective students website for information on how to register. For a la carte and contract registration, please see the dedicated section on the Prospective students website.

Contact information

Lecturer: Prof.dr. Ignas Snellen
Assistants: Dilovan Serindag, Christian Groeneveld, Orlin Koop