photograph showing thousands of satellites cross-hatching the night sky over New Zealand appeared so extraordinary the astrophotographer who captured it is fighting accusations it was created by AI.

To create his spectacular image – now viewed millions of times online – Brendan Larsen spent two hours in September snapping hundreds of photographs of the night sky over Mount Taranaki in the North Island.

Larsen, 51, says he set his camera up to take an unlimited number of eight-second-long shots, with a two-second gap in between each photo. "I left her running for two hours and captured 578 photos … That was the easy part."

The hard part came next. Larsen spent about 40 hours layering the individual photos – each of which contained about 25 satellites – over one another, using Adobe Photoshop. Much of the time was spent painstakingly erasing stars, to reveal the satellites.

"I could start to see the pattern emerging and realised: 'Wow, this looks really awesome.' I knew if I carried on it would look even better and more impressive in terms of satellite numbers."

The resulting image shows the sky inundated with about 1,400 satellites and 14,000 trails forming a dense crisscrossing pattern above the mountain.

When Larsen uploaded the image to his social media channels in mid-October, it quickly went viral, gaining him 15,000 new followers, clocking up tens of millions of views and igniting thousands of comments.

Some viewers dismissed the photo as AI – but Larsen understands why. "AI generating software is becoming so good it is becoming difficult to tell AI images from real images … especially if you're not familiar with the location or with astrophotography," he says. Still, it is "frustrating".

It is also exasperating, he says, to see his image downloaded and recreated by AI, with obvious flaws.

In anticipation of the AI accusations and backlash, Larsen documented his creative process on video, which he hopes will also allow viewers to form an emotional connection to the landscape.

As a child Larsen was "absolutely blown away" by the number of stars over parts of rural New Zealand. But he has noticed an increase in light pollution and the number of satellites over the six years he has been photographing the sky.

"It's interesting and fascinating seeing satellites, but it's also disturbing," he says.

"I've got about 10,000 comments on my Facebook page … nine out of 10 of the comments are like: 'Wow, beautiful photo, but horrifying, terrifying and really concerning about what's happening to the night sky.'"

About 16,000 working satellites are circling the planet, alongside tens of thousands of defunct spacecrafts, rocket parts and debris from payloads breaking up.

Studies have warned that metal particles from space activities – such as rocket launches and satellite reentries – could affect atmospheric chemistry and the ozone layer, while the UN has warned increased space activity poses risks to ground safety, darkness and astronomy.

While satellites don't yet overwhelm the sky to the naked eye, Larsen worries about the future state of the night sky. He hopes his image will ignite debate and reflection over how satellites can be used responsibly.

"We can raise awareness, and through that get a groundswell of support for protecting the night sky."