The Event Horizon Telescope (EHT) is an array of telescopes that uses a technique called Very Long Baseline Interferometry to form a virtual radio telescope with a dish diameter the size of the Earth. By linking together eight radio telescopes, the team achieved unprecedented sensitivity and resolution in their image of the supermassive black hole at the centre of the M87 star system.

In its citation statement for the award, the British Royal Astronomical Society (RAS) wrote: ‘The first image of a black hole has already inspired millions and will continue to do so. It represents an important milestone in human ingenuity and scientific endeavour, and is opening new doorways to study the physics of accretion around super-massive black holes in completely unprecedented ways. The realisation of the EHT represented a formidable challenge and was made possible only by decades of hard work and commitment by 13 institutions and more than 340 researchers. This is one of the finest examples of an achievement resulting from close collaboration by researchers from around the world.’

Sera Markoff, Professor of Theoretical High-energy Astrophysics at the University of Amsterdam and Vice-Chairperson of the EHT’s Scientific Council,: ‘We are delighted that such an important institute as the RAS acknowledges that ground-breaking science increasingly calls for large international teams. The wonderful thing about this award is that it also recognises young researchers, whose contributions to the analysis have often proved instrumental.’ In addition to Markoff and Porth, the team also included Dr. DooSoo Yoon, Dr. Gibwa Musoke, Dr. Koushik Chatterjee, Sebastiaan Selvi and a group of MSc students.

The RAS presents the Group Achievement Award for exceptional achievements by large consortia in all areas of astronomy. Previous winners were the Planck team in 2018 and the LIGO team in 2017. The team responsible for taking the first photograph of a black hole has attracted numerous awards and distinctions. For example, it previously won the Breakthrough prize, known as the ‘Oscar of science’ and featured in Time magazine’s annual end-of-year list. The EHT team was also awarded the 2020 Bruno Rossi prize by the American Astronomical Society.