The Wonders Of Radio Astronomy

Radio can unmask many hidden properties about the universe, including merging galaxies and Fast Radio Bursts. Professor Lisa Harvey-Smith speaks to All About Space about the mysterious majesty of the field

- Lee Cavendish

What can be learnt from radio astronomy that isn’t revealed in other spectrums of light?

Until about 400 years ago, we were, as human beings, completely blinkered. We didn’t have telescopes. We just had our own eyes and we just had the eyes that have evolved over millions of years of animal evolution on planet Earth. For that reason we can only see a tiny, narrow part of the spectrum. It was only much more recently that we started taking off the blinkers, certainly in the early 20th century. We started to realise there were other types of light that we could gather. And one of those invisible colours is radio waves.

We started to use those radio waves, not just for communication, but to passively receive information from space. Radio waves let you see the invisible. And they also let you find out so many layers of colours that we can’t see. For example, in the middle of our galaxy – the Milky Way – there’s so much dense, dusty gas that is completely black. All of that is hidden from view until we use infrared radiation, or if we use radio waves, and that’s what those different colours can teach us about how hot the gas is, about what it’s made of, what chemicals are up there in space and also the types of physical conditions in the stars.

A lot of the scientific goals of ASKAP are centred around galaxies, whether it’s their evolution, formation or population. What links them?