An international team led by Japan has completed four giant, 23-meter-diameter telescopes at the Roque de los Muchachos Observatory on La Palma, Spain. Part of the Cherenkov Telescope Array Observatory, the array is designed to capture high-energy gamma rays to study cosmic phenomena like black holes and dark matter.
New Telescope Array at Roque de los Muchachos
The completion of the four Large-Sized Telescopes marks a significant advancement for the Cherenkov Telescope Array Observatory, an international joint astronomical observation facility involving 25 countries and around 30 Japanese institutions. The observation site, known as the LST array, serves as a core facility of CTAO-North, which is under construction in the Northern Hemisphere. While the first of these telescopes, LST-1, was erected in 2018, the addition of LST-2, LST-3, and LST-4 enables the facility to conduct simultaneous observations from multiple directions, according to DongA Science.
An inauguration ceremony was held on the 15th local time at the Spanish island site. Takaaki Kajita, a distinguished university professor at the University of Tokyo, expressed hope that the new installations would open an important window into space.
Unlike traditional observatories, these structures operate without domes. Each unit has required an investment ranging between 25 and 30 million euros.
Probing the Early Universe and Dark Matter
The system is designed to observe gamma rays spanning an energy range from roughly 20 gigaelectronvolts up to several teraelectronvolts. The telescopes are built to detect Cherenkov light
—faint, momentary radiation emitted when particles travel faster than the speed of light in that medium during particle showers triggered when high-energy gamma rays enter Earth’s atmosphere. Analyzing these light signatures allows scientists to trace the rays back to extreme cosmic sources such as neutron stars and supernova explosions, according to Hidetoshi Kubo, who leads the Japanese research group.
The array will be capable of studying objects located approximately 12 billion light-years away, offering a view of the universe when it was 1.6 billion years after its birth. The project is part of a broader, long-term ambition:
By installing more than 60 telescopes, we aim to build the world’s largest gamma-ray astronomical observatory.
CTAO, via DongA Science
Operational Integration and Future Expansion
While the four LSTs are now physically complete, the team is entering a phase of system testing. We plan to prepare for full operations through test runs of the telescopes and system integration,
the organization announced, with full-scale observations expected to begin next year, as cited by DongA Science.
Locally, the site is slated for further growth.