Kate Middleton and Prince William Backstage! Exclusive Photos of Candid Moments at the Earthshot Awards

Jackson captured this intimate moment of the Duke and Duchess of Cambridge hand in hand as they departed the inaugural event, which was held at London's Alexandra Palace. Prince William launched Earthshot as a 10-year initiative to find solutions to the most pressing challenges facing the planet.

Jackson tells PEOPLE, "The Duchess obviously felt really proud of what [Prince William] had achieved with this project. Seeing first-hand this realization of this huge amount of work for him. It was a really special evening."

"These two have an incredible ability to shine a spotlight on global issues — and to work on this and make it happen has clearly been a big thing for [the Duke]," Jackson says of the couple (arriving at the awards, both in rewears per the evening's upcycled dress code).

Jackson captured this image of Kate making her remarks onstage: "If we don't act now, we will permanently destabilize our planet," she told viewers around the world. Behind the scenes, the royal "had been watching [the show] on the backstage TV," says Jackson. She and William "are proud of each other and are a strong team," he adds.

Oscar winner Emma Thompson, who said it was a "relief" to be asked not to buy anything new for the ceremony (she rewore a suit previously seen when William invested her as a dame!), shared a sweet moment backstage with the Duke of Cambridge.

Chris Martin led Coldplay in a performance that aired during the ceremony, with 60 cyclists providing the energy.

"The couple shared a joke with Emma Watson — they clearly got on really well with her and were having a good laugh," Jackson says.

Nigerian singer-songwriter-activist Yemi Alade got some outfit assistance behind the scenes.

Prince William looked over his notes for his speech, in which he told young viewers, "In the next 10 years we are going to act. We are going to find solutions to repair our planet."

"When William came back in from the stage from his speech, there was emotion in the room," Jackson shares.

"It was an incredible event," says Jackson, who has been capturing royal work around the world for 18 years. "Visually it blew me away. It was amazing, the stage floor being this constantly moving globe."

"There was great animation with [British rapper] KSI — they got on really well with him," says Jackson. "There was a lovely moment when they were all laughing together."

KSI shared on Instagram, "I asked Kate if she'd ever make a TikTok…She said no lol."

Ed Sheeran performed his new song "Visiting Hours" at the ceremony.

Jackson captured a still shot of the music program.

Yemi Alade delivered a rendition of her single "Rain" during the ceremony.

Legendary environmental filmmaker Sir David Attenborough took the stage to honor the 15 finalists "finding solutions to the world's challenges."

Hosts Dermot O'Leary and Clara Amfo worked closely with Prince William — and in a video shared ahead of the ceremony, were invited into Kensington Palace to discuss the show over tea.