Heriot-Watt chip links two telescopes into one sharper instrument

Phys.org reported on Oct. 30, 2026 that researchers at Heriot-Watt University developed a glass photonic chip that joined two telescopes to work as one larger instrument after successful on-sky tests at the CHARA Array in California. A photonic chip guides and manipulates light through channels rather than relying on conventional mirrors and lenses.

Georgia State University’s CHARA Array operates six telescopes that link together for detailed studies of celestial objects in extraordinary detail at its California site. When several telescopes work together, they function as one much larger instrument than any single telescope could be on its own.

The device conducted its initial on-sky observations at the CHARA Array in California, demonstrating that a glass chip only a couple of centimeters across can stand in for bulky instruments built from complex mirrors and lenses. On-sky observations are tests conducted under actual night-sky conditions rather than in a laboratory. The chip sits at the heart of CHARIOT, an instrument designed as a testbed for new photonic technologies.

Robert Thomson, a professor, and Aurélien Benoît developed the chip at Heriot-Watt University’s Institute of Photonics and Quantum Sciences. The project brought together researchers from the U.K., Germany and the United States, including colleagues from Cologne and Potsdam universities in Germany and the CHARA Array of Georgia State University in the United States.

Thomson said work on the program started more than 15 years ago. He said linking observations from several telescopes gives astronomers much sharper views because the telescopes function as one much larger instrument. “This is a significant milestone for a research program that began more than 15 years ago,” Thomson said.

Interferometry combines light from telescopes so they act as one sharper virtual instrument, achieving higher resolution. Existing arrays combine light using bulky instruments built from complex mirrors and lenses, while the chip performs that same beam-combining role in a glass device only a couple of centimeters across.

Ultrafast lasers inscribe channels within an innovative glass for the chip, reaching an unexplored spectral range for this fabrication method. The CHARIOT instrument lets researchers swap different photonic chips within hours to test improved designs rapidly. A testbed is an experimental platform used to test new equipment or methods.

CHARIOT gathered light from CHARA Array telescopes and recorded signals from stars during observing campaigns in 2024 and 2025. The campaigns took place before the results appeared in 2026, and the instrument picked up signals from stars fainter than the previous system could reach.

This research is part of astrophotonics, a growing field that brings together photonics and astronomy to address observational challenges with advanced light-based tools.

The achievement could transform future astronomical instrument design, researchers say, because it makes instruments smaller, more durable and simpler to upgrade while preserving precision for studies of distant stars and planetary systems. They also say the technology could eventually support studies of planetary system formation and change, help detect planets around other stars, and study those worlds in detail.

Dinkelaker said proving the technology works under real observing conditions is a major step forward. She called it progress for photonic tools in frontline astronomy research. Dinkelaker is the lead author from the Leibniz Institute for Astrophysics Potsdam. The research appeared in the journal Monthly Notices of the Royal Astronomical Society.