Astrophysicists working tirelessly to tackle the growing impact of satellite constellations have pioneered a new ultra-black coating as one possible way to mitigate the problem.

The team of researchers at the University of Surrey rigorously tested the material and its effectiveness as part of a wider effort to create a framework for evaluating future coatings and satellite surface designs.

Their goal is to address the broader challenge of protecting astronomical observations and the night sky. With current proposals to launch more than 1.7 million satellites into orbit, scientists worldwide have been urgently searching for ways to reduce their brightness in the night sky.

Reflected sunlight from spacecraft can create bright streaks and flares that interfere with telescope observations and large-scale surveys of the night sky, making it more difficult to detect faint objects such as asteroids, distant galaxies and other important astronomical phenomena.

In a study published in Monthly Notices of the Royal Astronomical Society, researchers demonstrated how Vantablack® 310 – an ultra-black coating developed by University of Surrey spinout Surrey NanoSystems, who co-authored the paper – could play a major role in reducing light pollution from satellites in low-Earth orbit.

To tackle the problem, the research team measured how Vantablack® 310 reflects light under a range of illumination and viewing conditions. They then used these laboratory measurements to simulate how a coated satellite surface would appear from the ground.

The simulations showed that the coating could make satellite surfaces significantly fainter, bringing their brightness close to the limit recommended by the International Astronomical Union for protecting astronomical observations. The findings suggest that ultra-black coatings could provide a practical way to reduce the impact of future satellites on astronomy and the night sky.

Astha Chaturvedi, lead author of the study and postgraduate researcher at the University of Surrey, said: "The night sky is one of humanity's oldest windows into the universe, but it is becoming increasingly difficult to see things.

"Our results show that relatively simple material choices could make a meaningful difference to how satellites affect astronomical observations without requiring major changes to mission design."

Vantablack® 310 – made from one of the world's darkest materials – reflects only around two per cent of incoming light, the researchers say, and the small amount of light it does reflect is distributed more diffusely, reducing the bright flashes commonly produced by reflective satellite surfaces.

Study co-author Dr Noelia Noël, a Senior Lecturer in Astrophysics at the University of Surrey, said: "Space is becoming increasingly crowded, creating challenges not only for astronomers but for everyone who values an unspoilt night sky.

"What is encouraging about this research is that it moves us beyond simply identifying the problem and towards developing practical, evidence-based solutions.

"As an astrophysicist at Surrey, I am particularly proud that a potential solution to this astronomical challenge has emerged from pioneering materials research at our own university."

She added: "Vantablack® technology grew from work involving my colleague Professor Ravi Silva and was developed and commercialised by Surrey NanoSystems, demonstrating what can be achieved when astrophysics, engineering and industry work together."

James Whitfield, Applications Scientist at Surrey NanoSystems and co-author of the study, said: "Satellite constellations offer enormous benefits, but their growing brightness presents a challenge for ground-based astronomy.

"Vantablack® 310 combines ultra-black performance across a wide range of viewing angles with the durability needed for low-Earth orbit. We are proud to work with the University of Surrey to help protect the night sky while supporting innovation in satellite technology."

The team is now preparing for an in-orbit demonstration aboard the Jovian-1 CubeSat mission – a student-led satellite programme involving the universities of Surrey, Portsmouth and Southampton.

The demonstration will test both the coating's performance in the space environment and whether the resulting change in brightness can be measured from the ground.

The work has also reached the international stage, with lead author Astha Chaturvedi invited to present the research at the United Nations Workshop on Dark and Quiet Skies in Vienna.

She said: "Our paper is fundamentally about addressing an important challenge for astronomy through an evidence-based approach.

"It shows how the astronomical community is working together with engineers and industry to develop realistic, scientifically grounded mitigation strategies that benefit both space activities and the protection of the night sky."

ENDS