Light-sensing terahertz sensor gives astronomers clearer glimpse of galaxies

The long-time dream of space scientists to view distant galaxies in detail has been limited by the technology available to detect and analyze stars and space activity billions of miles away. Now, researchers at the UCLA Samueli School of Engineering have developed an ultra-sensitive light-detecting system that could enable astronomers to view galaxies, stars and planetary systems in superb detail.

Unlike previous light sensors, the system developed at UCLA works at room temperature―compared to similar technology that only works in temperatures nearing -270°C, (-454°F). A paper detailing the advance is published today in Nature Astronomy.

A light-detecting space sensor developed at the UCLA Samueli School of Engineering works in the terahertz region and at room temperature, enabling astronomers to view galaxies, stars and planetary systems in superb detail.
A light-detecting space sensor developed at the UCLA Samueli School of Engineering works in the terahertz region
and at room temperature, enabling astronomers to view galaxies, stars and planetary systems in superb detail.

The sensor system detects radiation in the terahertz band of the electromagnetic spectrum, which includes parts of the far-infrared and microwave frequencies. It produces images in ultra-high clarity, and it can detect terahertz waves across a broad spectral range―reportedly ten times greater than current technologies that only detect such waves in a narrow spectral range.

Scientists envision the sensing system performing studies that currently require several different instruments. For instance, the system could identify the elements and molecules in those regions of space by seeing if their individual telltale spectral signatures are present.

"Looking in terahertz frequencies allows us to see details that we can't see in other parts of the spectrum," said Mona Jarrahi, a UCLA professor of electrical and computer engineering and research leader, in a statement. "In astronomy, the advantage of the terahertz range is that, unlike infrared and visible light, terahertz waves are not obscured by interstellar gas and dust that surround these astronomical structures."

The technology could be especially effective in space-based observatories, Jarrahi added, because unlike on Earth, terahertz waves can be detected without interference from the atmosphere.

Scientists believe the system can provide further insight into the composition of astronomical objects and structures and into the physics of how they form and die. The system could also uncover details on the interactions of gases, dust, and radiation that exist between stars and galaxies, and could reveal clues about the cosmic origins of molecules that could indicate whether a planet is hospitable to life.