New light-sensing camera may help detect alien life, dark matter

Researchers have developed one of the highest-performance cameras ever, which they say may be useful in the search for chemical signs of life on other planets, and in detecting the elusive dark matter.

The camera developed by the researchers at the National Institute of Standards and Technology (NIST) in the US is composed of more than 1,000 sensors, or pixels, that count single photons, or particles of light.

Described in the journal Optics Express, the camera consists of sensors made from superconducting nanowires, which can detect single photons.

They are among the best photon counters in terms of speed, efficiency, and range of colour sensitivity, the researchers said.

The team used these detectors to demonstrate Einstein's "spooky action at a distance," for example.

The theory referred to 'quantum entanglement' states that the measurement of one particle will instantly influence another particle, regardless of how far apart they are.

The nanowire detectors don't count false signals caused by noise rather than photons, according to the researchers.

This feature is especially useful for dark-matter searches and space-based astronomy, the researchers said.

The camera may be useful in future space-based telescopes searching for chemical signs of life on other planets, and in new instruments designed to search for the elusive "dark matter" believed to constitute most of the "stuff" in the universe, they said.

However, cameras with more pixels and larger physical dimensions than previously available are required for these applications.

They also need to detect light with longer wavelengths than currently practical.

The camera is small in physical size, a square measuring 1.6 millimetres on a side, but packed with 1,024 sensors (32 columns by 32 rows) to make high-resolution images.

The main challenge was to find a way to collate and obtain results from so many detectors without overheating, researchers said.

"My primary motivation for making the camera is NASA's Origins Space Telescope project, which is looking into using these arrays for analysing the chemical composition of planets orbiting stars outside of our solar system," said Varun Verma, an electronics engineer at NIST.

Each chemical element in the planet's atmosphere would absorb a unique set of colours, he said.

"The idea is to look at the absorption spectra of light passing through the edge of an exoplanet's atmosphere as it transits in front of its parent star," Verma explained.

"The absorption signatures tell you about the elements in the atmosphere, particularly those that might give rise to life, such as water, oxygen and carbon dioxide," he said.