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Radio Astronomy


Admission requirements

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


In this course you learn critical aspects of radio astronomy, allowing you to relate radio observations to the astrophysical sources they probe. We thus deal 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 course consists of presentation- and discussion sessions, complemented by written exercises and 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.

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 image deconvolution and self-calibration

  • The AGN phenomena and the brightest radio sources

  • Radio properties 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 astrophysical phenomena. You can compare how various radio telescopes and observing modes can be used optimally to investigate the astrophysical processes that generate long wavelength emission.

After this course you can:

  • Write a clear, concise report describing a radio-interferometric data reduction and subsequent image analysis;

  • Develop a data reduction process from raw radio interferometric data to science-quality images;

  • Write an observing proposal for an appropriate radio telescope to answer a scientific question;

  • Analyse quantitatively how radio interferometric concepts affect a specific scientific result;

  • Explain if and why certain radio image features are astrophysical or not;

  • Analyse to what extent signals are mutually coherent;

  • Identify common radio-astronomical data visualizations with their axis labels removed;

  • Identify the type of astrophysical object visualized in a figure;

  • Perform basic Fourier-analyses, such as deriving a SINC function andqualitatively predicting the telescope’s response to a small collection of elementary shapes;

  • Describe (the function of) common components involved in a telescope’s signal processing;

Soft skills

During this course, you will also learn about:

  • Assessing each other’s work

  • Giving effective feedback

  • Managing (Python) source code

  • Reproducible data analysis

  • Working as part of a large collaboration

  • Finding and reviewing relevant literature

  • Scientific writing

  • Proposal writing


See Astronomy master schedules

Mode of instruction

  • Lectures

  • Literature study

  • Group projects

  • Written exercises

  • Data processing tutorials

  • Data reduction and scientific reporting

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

  • Report on practical assignment in radio data processing (40% of final grade, must be submitted before Dec 15, teacher-assessed)

  • Several smaller assignments (10%-15% of final grade each), peer-assessed based on clear rubrics. Includes appeal-process.

Assessment method

There will not be a traditional final exam. Instead, you are assessed
based on various assignments. Deadlines:

  • Sep 27: 15%, Group report (up to 8 groups of 3+ people, chosen
    randomly by teachers). Galactic hydrogen detection experiment:
    instrument and experiment design (including expected
    results). Peer-assessed by "design review panel" composed of
    members of other teams. Teachers review and confirm grade &
    provide feedback.

  • Oct 11: 15%, Group report (same 8 groups of 3+ people as previous
    assignment): Analysis of actual observations of Galactic hydrogen
    with your own previously designed instrument. Peer-assessed by "scientific review panel" composed of members of other
    teams. Teachers review and confirm grade & provide feedback.

  • Oct 25: 15%, Individual report. Observing proposal. Peer-assessed
    by "time allocation committee" composed of other
    students. Teachers review and confirm grade & provide feedback.

  • Nov 1,8,22,29: 15% , Pair presentation (pairs randomly chosen by
    teachers). "Journal club ": pairs will present papers about
    specific radio astronomical subjects. Teacher-assessed.

  • Dec 15: 40%, Pair report (pairs chosen by students
    themselves). Data reduction and scientific interpretation of a
    data set from a professional radio
    interferometer. Teacher-assessed.

All assessments will be done using rubrics published on BrightSpace.
Members of review panels that propose realistic, well justified scores and write good feedback to the authors of the work they reviewed, may
be awarded half a point bonus on top of their own report’s marks at
the teachers’ discretion.


Brightspace will be used to communicate with students and to share lecture slides, homework assignments, and any extra materials. You must enroll on uSis 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 (required, free online HTML version here)

  • 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