1. The internet travels in optical fibres as light

2. Light can give us clues about planets in other star systems

When you look at the night sky, you are looking into the past.

The light we see from the Sun is about eight minutes old.

The light from Proxima Centauri – the nearest star to Earth after the sun – is more than four years old by the time it reaches us.

Astronomers can study the colour of light to learn about planets orbiting distant stars. Tiny shifts in starlight can reveal whether a star is wobbling because a planet is pulling on it.

But those shifts are incredibly small, and go much further back than just four years (in fact, hundreds of millions of years!). To find them, astronomers need extremely precise tools.

Optical frequency combs can act like rulers for light, helping researchers measure tiny changes in starlight. COMBS researchers are working towards more reliable and compact comb technologies that could support the search for Earth-like planets.

3. Lightning can tell you how far away a storm is

You have probably heard the trick for estimating how far away a storm is: count the seconds between seeing lightning and hearing thunder.

Light travels much faster than sound, so we see the lightning before we hear the thunder. The longer the gap, the further away the storm.

That simple trick uses light and time to estimate distance.

Our COMBS researchers are using the same bigger idea – light as a measurement tool – in much more advanced ways.

By sending laser light through optical fibres and measuring how that light changes, researchers can detect vibrations and environmental changes along the fibre. 

This could help track storms, monitor drainage systems and understand how infrastructure responds during extreme weather.

Our hope is that optical frequency combs could make these measurements even more precise.

4. The best clocks do not tick – they use light

Old clocks used swinging pendulums. Modern phones use electronic signals. The most advanced clocks use atoms and light.

Optical atomic clocks measure the vibrations of atoms using light. These vibrations happen fast and can provide an extraordinarily stable way to measure time.

But there is a challenge: optical atomic clocks operate at frequencies far beyond what everyday electronics can easily count.

Optical frequency combs help bridge that gap. They translate the precision of optical clocks into signals we can use.

Optical clocks are the most accurate way to measure a second, and they’re integral to navigation, communications, space exploration and fundamental science.

5. Light can reveal what the eye cannot see

For centuries, scientists have used light to reveal hidden information about the world.

It can reveal what materials are made of, how chemicals behave and what is happening inside living tissue.

This is the idea behind spectroscopy – or ‘ghost watching’ as it is in Latin – studying how light interacts with matter.

Our COMBS researchers are exploring how advanced light-based tools could improve biomedical imaging, including research into triple-negative breast cancer cells.

With optical microcombs, researchers hope to speed up some imaging and analysis processes, potentially reducing processing times from hours to seconds.