nl en

Radio Astronomy


Admission requirements

Leiden Astronomy bachelor's courses Analyse 3NA (Fourier transforms) and Radiative Processes, knowledge of Unix and Python.


In this course you learn all aspects of radio astronomy, allowing you to relate radio observations to the astrophysical conditions in radio sources. Radio astronomy deals with both the electromagnetic processes in the Universe that produce radio emission, as well as the workings of the telescopes that measure this radio emission.

The lecture series, including guest lectures by experts, are complemented by practical computer classes, where you are coached to process state-of-the-art radio interferometry data. The course covers the whole spectrum from Mega-Hertz to sub-millimetre radiation and from the cosmic dawn to galactic star formation, focusing on how to interpret data with different frequency and spatial resolution. Also, polarimetry and variability are covered in this course.

In particular, the following aspects are covered:

  • Detection of radio waves, telescope and receiver characteristics

  • The workings of interferometers and their response

  • Data processing techniques, such as clean and self-calibration

  • The AGN phenomena and the brightest radio sources

  • Radio diagnostics of the cold and warm interstellar medium

  • Special radio sources, such as pulsars and masers

  • Design and data flow characteristics for interferometers, like LOFAR, VLBI, ALMA, SKA

  • Spectral line observation of molecules and HI throughout the universe

Course objectives

After this course you are ready to engage in scientific discussions that concern radio observations of any astrophysical phenomenon. You can compare how various radio telescopes and observing modes can be used optimally to determine the astrophysical processes that generate long wavelength emission.

In particular, after this course you can:

  • Quantify the sensitivity and resolution characteristics of specific telescopes

  • Verify the technical limits of the signal flow in telescopes and interferometers, including sampling and mixing

  • Apply various concepts in radio interferometry, like uv-coverage, weighting, deconvolution and hybrid mapping in discussions on scientific results

  • Distinguish various thermal and non-thermal processes generating radio emission

  • Categorize the various radio objects and phenomena in the universe

  • Perform basic sensitivity calculations in order to schedule or propose radio observations

  • Predict the response to spatial structures of radio telescope and interferometers in particular

Soft skills

During this course, you are trained in:

  • Relating abstract concepts to specific technical implementations

  • Finding your way through complex processing problems through trial and error.

  • Deducing ways to solve an observational problem from literature and documentation


See Astronomy master schedules

Mode of instruction

  • Lectures

  • Written exercises

  • Data processing tutorials

  • Data reduction and scientific reporting assignments

  • A field trip to ASTRON, JIVE, LOFAR, Westerbork and Dwingeloo

Assessment method

  • Report on practical assignment in radio data processing (35% of final grade, must be completed at least two weeks before the written exam)

  • Written exam (65% of final grade)


Blackboard will be used to communicate with students and to share lecture slides, homework assignments, and any extra materials. You must enroll on Blackboard before the first lecture. To have access, you need a student ULCN account.

Reading list

  • Essential Radio Astronomy (J.J. Condon, S.M. Ransom), ISBN: 9781400881161 (recommended)

  • Synthesis Imaging in Radio Astronomy (G.B. Taylor, C.L. Carilli, R.A. Perley), ISBN 1-58381-005-6 (recommended)

  • Interferometry and Synthesis in Radio Astronomy (A.R. Thompson, J.M. Moran, G.W. Swenson Jr.), ISBN 9783319444314 (recommended, free download here)


Via uSis. More information about signing up for your classes can be found here. Exchange and Study Abroad students, please see the Prospective students website for information on how to apply.

Contact information

Lecturers: Dr. M.A. (Michiel) Brentjens and Dr. T.W. (Tim) Shimwell
Assistants: Rafael Mostert, Martijn Oei, Frits Sweijen