Billie Eilish kept it simple for her remote performance at Prince William's Earthshot Prize awards ceremony on Friday evening, wearing a comfortable grey sweatshirt as she sat at her piano to sing 'My Future'.
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The Grammy-award winner was part of a stellar line-up that included Annie Lennox, Ellie Goulding and the Beyoncé-backed R&B duo Chloe x Halle that performed during the event.
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Billie prerecorded her performance of 'My Future' from her home in Los Angeles, and she was joined by her brother Finneas.
The Prince and Princess of Wales were greeted with a standing ovation as they took to stage for the start of the ceremony, which referenced the colonists who came to Boston 400 years ago. Elizabeth Solomon, a member of the Massachusetts tribe at Ponkapoag, asked attendees to "respect the lands and waters".
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Dubbed Prince William's "Superbowl moment," the glitzy ceremony drew an A-list crowd at the MGM Music Hall at Fenway in Boston. Among those presenting awards were Oscar-winning actor Rami Malek, Home Alone and Schitt's Creek star Catherine O'Hara and environmental activist and Big Little Lies star Shailene Woodley.
Earthshot Prize council members Sir David Attenborough and Cate Blanchett will both provide voiceovers during the ceremony, which will be presented by UK broadcaster Clara Amfo and US actor Daniel Dae Kim.
Ambassador Caroline Kennedy, daughter of President John F Kennedy, whose “Moonshot” speech about space travel inspired the Earthshot prize, will also take part with her son Jack Schlossberg, JFK’s only grandson.
The ambitious, decade-long, global Prize programme aims to discover and scale up solutions to the planet's biggest environmental challenges.
Among the ideas competing this year are a cleaner-burning stove initiative in Kenya and a bubble barrier made in the Netherlands to prevent plastics entering oceans.
William described the finalists as "innovators, leaders, and visionaries" and said they proved there are "many reasons to be optimistic about the future of our planet".
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He went on to say: "They are directing their time, energy, and talent towards bold solutions with the power to not only solve our planet's greatest environmental challenges, but to create healthier, more prosperous, and more sustainable communities for generations to come."
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