Astronomers in Africa and Europe reacted with joy to the announcement of the construction of Africa’s first millimeter radio telescope.

The Africa Millimeter Telescope will fill a gap in the coverage of the Event Horizon Telescope (EHT), a global network of telescopes capable of receiving and analyzing radio waves around 1 millimeter in length – in 2019 they released the full first image of a black hole’s edge, known as the event horizon

The telescope will be located on or near Table Mountain in the Gamsberg Nature Reserve in Namibia. It will be a converted 15-meter telescope, currently located in La Silla, Chile, which is donated by the Onsala Space Observatory to the Sweden and the European Southern Observatory, headquartered near Munich, Germany.

The project, confirmed late last year, is “a further step towards consolidating Africa’s position as a competitive and capable global player in the field of astronomy”, Charles Takalana said. , Head of the Secretariat of the African Astronomical Society in Cape Town, South Africa. The telescope will “fill a missing observation window on the continent” and be crucial for African astrophysical communities, adds Roger Deane, who directs the Wits Center for Astrophysics at the University of the Witwatersrand in Johannesburg, South Africa.

The Africa Millimeter Telescope is a collaboration between Radboud University Nijmegen in the Netherlands and the University of Namibia in Windhoek. It will take about five years before the telescope sees the first light. The project will cost around $25 million, including construction, operation and outreach projects in the southern African country. Half of its funding comes from Radboud University. Other funders include the University of Namibia, the European Southern Observatory and the Netherlands School of Astronomical Research in Leiden.

The telescope team is working on what is called a critical design review, which will help determine the exact location of the observatory on the mountain, whether it should be adjacent to the mountain or located on another site ; and whether additional funds will be required.

Telescopes in the millimeter wavelength range can image the event horizon of a black hole, says project leader Marc Klein Wolt, who is also managing director of the Radboud Radio Lab at Radboud University. At longer wavelengths “you only see a blob, but at millimeter wavelengths you start to see the edge.”

In 2019, the EHT team released a famous image of the supermassive black hole at the center of the M87 galaxy. It was the first image to show the outline of a black hole’s event horizon. “This image was the start of a new science, just as the first observation of gravitational waves was the start of a new science,” says Klein Wolt. Radboud University astrophysicist Heino Falcke, who announced the first image of the black hole, will be the chief scientist of the Africa Millimeter Telescope.

“You have to have a telescope in the southern hemisphere, in southern Africa, to make all these connections [to other telescopes in the network]“, explains Klein Wolt. “It would allow you to observe [the sky] while the Earth spins,” he adds.

However, the EHT will only require about a fifth of the Africa Millimeter Telescope’s total observing time, says astronomer Michael Backes, the project’s co-principal investigator, based at the University of Namibia. “The lion’s share of time will be available for Namibian astronomers to develop their programs,” he says.

Possible projects in Namibia include monitoring variations in brightness of small and large black holes in collaboration with optical telescopes and γ-ray telescopes such as the High Energy Stereoscopic System (HESS), also located in Namibia, and the project of the Cherenkov telescope. Array in Chile, says Backes.

Over the past two decades, telescopes have been installed across southern Africa. Countries with relatively clear skies and low population densities are ideal for astronomy. The telescopes cover a wide range of wavelengths – from the Large Optical Telescope in Southern Africa and the MeerKAT Radio Telescope in South Africa to the HESS Telescope in Namibia. Late last year, the Square Kilometer Array (SKA) Observatory began awarding contracts for the construction of its giant radio telescope, which will have thousands of dishes in South Africa and a million antennas in Australia. , once the project is complete.

However, finding trained scientists and engineers on the continent has always been a challenge, says Carla Sharpe, Africa program manager at the Cape Town-based South African Radio Astronomy Observatory, which is not yet involved in the Africa Millimeter Telescope. Since 2005, when it threw its hat in the ring to host the SKA, South Africa has awarded over 1,000 astronomy and engineering scholarships to fill this talent gap locally and in countries. partners of SKA Africa, including Namibia.

Backes says he hopes the Africa Millimeter Telescope will help expand Namibia’s astronomy community. Klein Wolt adds that the team is still seeking additional funding to be able to finalize the location of the telescope and continue training astronomers in Namibia.

Projects such as the Africa Millimeter Telescope will help deliver a larger agenda in Africa in the fields of astronomy, radio astronomy and engineering, which are needed to help develop the continent, Sharpe said.