I took this shot in a big open field near my home in Boston, Massachusetts. It was Midsummer and the sky was perfectly clear – or as clear as it gets near cities these days. Light pollution is changing how we see the stars and not for the better.

I work on a large-format, 8x10 camera. It isn’t electronic, just a big black box with film in it. It’s a slow process so I can be out until three or four in the morning. It takes time to set up all of my gear and some images can take an hour to fully expose. It’s time-consuming, but that’s part of the joy: standing alone in nature staring at the sky is what I’d spend my time doing anyway, so why not make a photo of it?

It was the colour of this shot that grabbed me. Blue is the colour of the void, whether it’s the deep sea or the deep sky. It also speaks to the mystery of space and nature: the idea that this starlight we see every night is millions of years old, and has travelled such unimaginable distances, is something I’ll never get over.

I’m not a scientist by any means, but I’ve always taken a general interest in scientific developments, ever since childhood. Only when I started to research the history of photography did I realise how space has always interested photographers, and how it helped to found the discipline.

All of those early types of photography – daguerreotypes, cyanotypes – were instrumental in our first understandings of the cosmos. Some of the most technically advanced cameras were developed in order to see deep into space. And some of astronomy’s greatest breakthroughs have come from hi-tech lenses, revealing things the human eye never could.

One of my greatest inspirations in pursuing space photography was Galileo. I remember seeing the drawings of the moon and Jupiter in his book Sidereus Nuncius (Sidereal Messenger) of 1610, and his sunspot drawings in Istoria e Dimostrazioni (History and Demonstrations) of 1613 when I was in my 20s. His drawings of the cosmos were just so enchanting to me. I couldn’t read the Italian text, but the awe I experienced when I saw the pictures was life-changing. It taught me the power of an image, no matter how simple. Galileo was one of the first to use a telescope, and among the first to try to map the cosmos. In some ways, this shot is a homage to him and his efforts. My camera provides its own vision of the mysteries of space.

There’s also a personal reason for my love of the night sky: my childhood. My father loved watching light travel across the landscape. I think it was his sense of wonder that inspired me. Taking long walks together became an important bonding experience for us, being alone with each other underneath the night sky.

I suppose my work is quite unusual. In a world of instant images, it’s strange to shoot on such a clunky old camera. I wouldn’t say I’m reacting against the speed or instantaneity of today’s photographic world, it’s just what I’ve always done and what I’ll continue doing.

It’s getting harder to take these images. Light pollution makes it increasingly hard to find a really dark night sky where you can see constellations and stars. And it’s having a detrimental impact on the natural world – changing bird migration patterns and messing with the ecosystem.

But it’s also a shame for humanity. The feeling of staring at the vastness of the night sky inspires a sense of awe that’s pretty universal. That’s important at a time when people are becoming more divided. Looking at something so huge makes humans think we are pretty insignificant, maybe we should depend on those around us and start looking after the only Earth we have.

Barbara Bosworth’s CV

Born: Cleveland, Ohio, 1953.

Training: MFA at Rochester Institute of Technology.

Influences: John Constable, Caroline Herschel, Emily Dickinson, Anne Carson and Asher B Durand.

High point: “Each day photographing.”

Low point: “I don’t have any.”

Top tip: “Make pictures, read a lot and go where that takes you.”