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ASTRON is responsible for the operations of the Westerbork Synthesis Radio Telescope (WSRT) and the Low Frequency Array (LOFAR).


The astronomical research at ASTRON is closely aligned with the strengths of our facilities LOFAR and WSRT-APERTIF.

Diversity & Sustainability

ASTRON is committed to achieving a fair, welcoming, and sustainable work environment for all.


Met onze radiotelescopen nemen wij de meest zwakke signalen uit het heelal waar. Daardoor zijn zij kwetsbaar voor elektromagnetische storing. Met het tijdig treffen van de juiste maatregelen kan storing worden voorkomen.

Wireless Data Lab

Draadloze techniek lijkt vanzelfsprekend, maar de ontwikkeling ervan gaat niet vanzelf. Daarom hebben we bij ASTRON een proeftuin ingericht; het Wireless Data Lab.

Making discoveries
in radio astronomy

ASTRON is the Netherlands Institute for Radio Astronomy, and is part of the Institutes organisation of NWO.

Astronomers Discover Fast Radio Bursts That Skewer Nearby Galaxy

Astronomers have found five new Fast Radio Bursts with the upgraded Westerbork radio telescope array. The telescope images revealed that multiple bursts had pierced our neighbouring Triangulum Galaxy. This allowed the astronomers to determine the maximum number of otherwise invisible atoms in this galaxy for the first time.

Published by the editorial team, 12 April 2023

ERC Advanced Grant for research into the origin of fast radio bursts from space

Jason Hessels, Professor of Observational High-Energy Astrophysics at the University of Amsterdam and Chief Astronomer at ASTRON, has been awarded a €3.5 million ERC Advanced Grant to search for the origin of fast radio bursts. Among other things, the research money will be used to develop new hardware to set up a coordinated network of European radio telescopes to study repeating FRBs in more detail.

Published by the editorial team, 30 March 2023

Animation explaining the workings of LOFAR

We have created an animation, which briefly explains the workings of our LOFAR radio telescope.

Published by the editorial team, 23 March 2023

NAC 2023 to be held in Leeuwarden in May

The 78th edition of the Nederlandse Astronomen Conferentie (NAC) will be held this year in the Westcord WTC hotel in Leeuwarden from 15 to 17 May.

Published by the editorial team, 6 March 2023

ASTRON astronomy groups focus on LOFAR and SKA

Major upgrade of International LOFAR Telescope approved

Michiel Brentjens wins Teacher of the Year 2022 award

Jessica Dempsey nominated for Drenthe Woman in the Media Award

People of ASTRON: Klaas Kliffen

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First release of the Rapthor pipeline!

© CC

Rapthor is a pipeline to process LOFAR data and produce high-quality images. Specifically, it performs direction-dependent calibration in a fully automated self-calibration loop.

The image is a result produced by Rapthor, and has a maximum colour scale of 3 mJy/beam, and thus many sources that are of sub-mJy/beam brightness are visible. It is made from 12 MHz bandwidth of an HBA observation, and reaches an expected noise level of 150 µJy, which for such an integration time and bandwidth is approximately the best that can be achieved with LOFAR NL.

In the future, LOFAR users can directly request the high-quality images from Rapthor when proposing observations, or users can run (and modify) the pipeline themselves. Rapthor makes use of various modern pipelining paradigms, such as for example the common workflow language (CWL). This makes it easy to maintain and support development, and reuse parts of our pipeline for different science cases. Development of the pipeline is helping to push our existing processing software (e.g. DP3, WSClean, PyBDSF) to new limits, and these improvements are already eagerly used by various (expert) users outside of Rapthor. Finally, it also provides a platform to perform new high-performance computing research, and various projects are underway to come up with better and faster algorithms, for example by making use of GPUs.

By releasing our software, we are telling the community that the pipeline is ready to be used by others. Such users can take a look at the release notes and the generic documentation. Our current release targets the processing of Rapthor HBA NL data, but this is just the beginning — in the future, this will be extended to support long baseline and LBA data and to make use of all LOFAR2 capabilities.

ASTRON daily image.

Cursus: Toegepaste RF-techniek

Mon 06 Nov 2023 - Thu 09 Nov 2023

De cursus Toegepaste RF-techniek bestaat uit een theoriegedeelte (75%) en hands-on sessies in ons eigen lab (25%).
Deelnemers aan deze cursus dienen een hbo werk- en denkniveau te hebben. De deelnemer kent de basisbegrippen van elektronica. Parate kennis van wiskundige concepten is niet vereist, maar komt wel aan de orde bij de transmissielijntheorie. In de cursus wordt ook complexe rekenwijze toegepast.


Latest tweets

Our congratulations go out to Anna Bilous and her colleagues, for this intriguing paper, which was published in Nature.

Every year on May 4th we put our Westerbork telescopes into mourning mode, to remember all the victims who fought for our freedom. Watch the video that we made a couple of years ago in cooperation with @kampwesterbork, demonstrating this. #4mei #Memorial

Our radio telescopes don't need the darkness to function, but they do need quiet skies, free from radio interference. This month is Dark and Quiet Skies month. What can you do to keep our skies dark and quiet?

Daily Image of the Week: Blast from the past

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