Event Horizon Telescope (EHT)

EHT

The Event Horizon Telescope (EHT) is an international collaboration - including over 300 scientists from more than 20 countries - capturing images of black holes using a virtual Earth-sized telescope. In active galaxies where the central black hole is not resolved, the EHT enables studies of jets and jet formation mechanisms at the smallest physical scales. It utilises Very Long Baseline Interferometry (VLBI) at higher frequencies (100-350GHz) than the European VLBI Network, which operates in the 1-43 GHz regime.

The EHT has published the first two images of supermassive black holes. In april 2019 the billion solar mass black hole in the core of the nearby massive elliptical galaxy M87 was revealed (Pōwehi). In 2022 the centre of our own Galaxy was shown to harbour a million solar mass black hole, Sagittarius A*.

JIVE Participation

The work in JIVE focuses on the data management and calibration of EHT observations, including the development of new software components in the CASA package. The EHT data processing occurs in two pipelines for cross verification, one of which (rPicard) is based on CASA and the tools developed at JIVE.

Website

https://eventhorizontelescope.org

Contact

Huib van Langevelde

EHT NEWS

Huib van Langevelde featured at exhibition at the Rijksmuseum Boerhaave

29/06/2022
On 23 June 2022, the Dutch Minister of Education, Culture and Science Robbert Dijkgraaf opened the newly furnished Big Questions theme room of the Rijksmuseum Boerhaave in Leiden, the Netherlands. The new content of the exhibition features an interview of JIVE Chief Scientist and Event Horizon Telescope (EHT) Collaboration Project Director Huib van Langevelde, who also participated in the opening, giving a keynote address.

Astronomers reveal first image of the black hole at the heart of our galaxy

12/05/2022
Astronomers have unveiled the first image of the supermassive black hole at the centre of our own Milky Way galaxy. This result provides overwhelming evidence that the object is indeed a black hole and yields valuable clues about the workings of such giants, which are thought to reside at the centre of most galaxies. The image was produced by a global research team called the Event Horizon Telescope (EHT) Collaboration - including participation in the Netherlands of astronomers and technicians from University of Amsterdam, Radboud University, Leiden University, University of Groningen, JIVE ERIC and ASTRON - using observations from a worldwide network of radio telescopes. The image has been unveiled by JIVE Chief Scientist and EHT Project Director Huib Jan van Langevelde at the European Southern Observatory Headquarters in Garching (Germany), one of the press conferences organised by the EHT Collaboration around the world.

EHT pinpoints dark heart of the nearest radio galaxy

11/11/2021
An international team anchored by the Event Horizon Telescope (EHT) Collaboration, which is known for capturing the first image of a black hole in the galaxy Messier 87, has now imaged the heart of the nearby radio galaxy Centaurus A in unprecedented detail. The astronomers pinpoint the location of the central supermassive black hole and reveal how a gigantic jet is being born. Most remarkably, only the outer edges of the jet seem to emit radiation, which challenges our theoretical models of jets. This work, led by Michael Janssen from the Max Planck Institute for Radio Astronomy in Bonn and Radboud University Nijmegen is published in Nature Astronomy on 19 July 2021.

Astronomers Image Magnetic Fields at the Edge of M87’s Black Hole

10/05/2021
The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole, has revealed today a new view of the massive object at the centre of the M87 galaxy: how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, is able to launch energetic jets from its core.

Telescopes unite in unprecedented observations of famous black hole

10/05/2021
In April 2019, scientists released the first image of a black hole in the galaxy M87 using the Event Horizon Telescope (EHT). However, that remarkable achievement was just the beginning of the science story to be told. Scientists from JIVE contributed to this global effort.

2021 Royal Astronomical Society Group Achievement Award presented to EHT

08/01/2021
The Event Horizon Telescope (EHT) collaboration is excited for having been granted by the Royal Astronomical Society (RAS) with the 2021 Group Achievement Award (A). The EHT is a global network of synchronised radio observatories that work in unison to observe radio sources associated with black holes. In April 2019, the EHT team showed the world the first image of the shadow cast by the black hole in M87, made possible by the enormous baselines which give the EHT its exquisite angular resolution.

Wobbling Shadow of the M87* Black Hole

23/09/2020
In 2019, the Event Horizon Telescope (EHT) Collaboration delivered the first image of a black hole, revealing M87*-the supermassive object in the center of the M87 galaxy. The EHT team, including researchers from JIVE, has now used the lessons learned last year to analyze the archival data sets from 2009-2013, some of them not published before. The analysis reveals the behavior of the black hole image across multiple years, indicating persistence of the crescent-like shadow feature, but also variation of its orientation-the crescent appears to be wobbling. The full results appeared today in The Astrophysical Journal.

Huib van Langevelde new director Event Horizon Telescope

17/07/2020
Huib van Langevelde (Chief Scientist in JIVE, Dwingeloo, also Professor of Galactic Radio Astronomy at Leiden) has been selected as the new director of the Event Horizon Telescope (EHT). The EHT is a collaboration involving about 350 scientists from 18 countries. The EHT combines sub-millimeter telescopes around the world, including the ALMA array in Chile, and published the first image of a Black Hole in 2019.

Astronomers Capture First Image of a Black Hole

10/04/2019
The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole, has revealed today a new view of the massive object at the centre of the M87 galaxy: how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, is able to launch energetic jets from its core.