Watch: Prince William reveals details of the first Earthshot Prize awards ceremony
Prince William announced his most ambitious project more than a year ago - offering millions of pounds over 10 years to solve the big problems facing the planet.
William and the Royal Foundation launched the Earthshot Prize, which will offer funding to 50 projects that put forward solutions to some of the biggest challenges facing earth.
With his father and grandfather as his eco-inspiration, the Duke of Cambridge will view this as his legacy project, and a defining symbol of his royal work.
But what does it involve - and who else is part of the project?
What does the name Earthshot mean?
The name comes from the 1960s US project to get a man to the moon.
John F Kennedy set a challenge in 1960 to get a man on the moon within 10 years, a goal which seemed out of reach at the time.
It was called the Moonshot, and is the basis for the name Earthshot.
Neil Armstrong walked on the moon in 1969 after years of hard work by scientists, mathematicians and more, and William wants to see the same spirit harnessed to develop solutions to the biggest problems the earth faces.
What is an Earthshot?
There are five Earthshots, which the team describe as "simple but ambitious goals for our planet which, if achieved by 2030, will improve life for us all, for generations to come".
The categories are: Protect and restore nature; Clean our air; Revive our oceans; Build a waste-free world; Fix our climate.
The team has said the categories are "underpinned by scientifically agreed targets including the UN Sustainable Development Goals".
The Earthshots are the main part of the Nobel-style competition, which seeks to be a carrot rather than a stick approach, encouraging active solutions to the world's challenges and scaling them up.
What does the Earthshot Prize mean?
William has set up a prize council which includes people like Shakira, Cate Blanchett and Sir David Attenborough, who will assess the projects which could potentially win.
There's £1m investment and tailored support available for each winner.
However it's not as easy as filling in a form with a good idea. The council is working with nominating partners around the world, who are going to submit the potential winners.
They will "seek out solutions from across the globe" and make their recommendations, which will then be screened by auditing and consulting firm Deloitte.
A shortlist will then be created by a panel of experts, before they go to the council. The council will decide one winner per category and they will be announced at a ceremony.
Prince William named London as the first location for the awards ceremony, which will be held at Alexandra Palace on 17 October.
Who will be judging the contest?
The star-studded panel includes both well-known faces and industry experts.
Cate Blanchett, Shakira, Queen Rania Al Abdullah and Sir David Attenborough are on the council, alongside footballer Dani Alves, Hindou Oumarou Ibrahim, an activist from Chad, philanthropist Jack Ma, and former PepsiCo chairman Indra Nooyi.
It also includes former executive secretary of the United Nations Framework Convention on Climate Change Christiana Figueres, Fijian youth activist Ernest Gibson, and Luisa Neubauer, one of the co-organisers of the climate strike movement initiated by Greta Thunberg.
Former astronaut Naoko Yamazaki, economist and international development expert Dr. Ngozi Okonjo-Iweala and basketball hall of famer and environmentalist Yao Ming take the final seats.
They will be responsible for giving out £5m every year for 10 years, to five projects each year.
The prizes will be awarded until 2030.
How do people get involved?
The awards night will be shown on BBC One on 17 October, so the public can watch the big show.
Ahead of that, schoolchildren aged 10-15 can be part of Generation Earthshot, which encourages them to help develop solutions to the planet's problems.
Of Generation Earthshot, William said: "Education is so important in protecting our planet. We need that collective confidence that pushes us forward and says we can do it."
The free teacher toolkit includes worksheets and videos to introduce the problems to pupils in a school environment before encouraging them to work together to come up with solutions.
The awards night will be shown on BBC One on 17 October, so the public can watch he big show.
The team said: "Prize winners can become environmental heroes for Generation Earthshot, inspiring them to follow their progress and shaping their own actions going forward. In turn, Generation Earthshot aims to inspire and build a pipeline of future Earthshot winners."
From September pupils will be able to submit their ideas and get an Earthshot certificate.
William's team think the projects that are needed to solve the world's biggest problems already exist, they just need to be scaled up.
The Earthshot website explains: "The projects that will win The Earthshot Prize are the outstanding actions and initiatives that are demonstrating positive effects on people’s lives and progress towards our Earthshots.
"By identifying and highlighting these solutions, The Earthshot Prize will inspire and celebrate new, collaborative action to meet the environmental challenges we face."
The group will of course want to keep details under wraps until they have been vetted, but they have shared some projects on their website and social media which could offer clues about the candidates.
One of those who will suggest projects to the panel is Robert Irwin, son of the late Steve Irwin, TV's crocodile hunter.
He said: "Not only do we support many different conservation projects all over the world from tiger conservation in Sumatra to rhino and cheetah conservation in Africa, but we also support a lot of projects here in Australia as well.
"We have the largest and longest running crocodile research project in the world and by doing this we can really get an idea of the health of aquatic ecosystems, which ties in really well with The Earthshot Prize's pillar of Reviving Our Oceans."
Earthshot has also highlighted how cities "are delivering a sustainable and equitable recovery from the COVID-19 crisis, while reducing emissions with ambitious climate action, and cleaning our air".
C40 is a network of cities and their mayors who are working together to try to cut emissions in line with the global goals.
They have highlighted a scheme in Quezon City in the Philippines, where the mayor Joy Belmonte has developed a sensor network to "understand patterns in air pollution so policies can be targeted at communities that will benefit most".
And they have praised work in Addis Ababa where C40 is trying to improve the pollution monitoring network in the city.
Who knows, a project near you could soon be award-winning.
Why did William want to launch this?
It's not unusual for senior royals, particularly those of William's position in the line of succession, to have legacy projects which are a focal point for them and their households.
For example, Prince Charles has the Prince's Trust, which he founded more than 50 years ago, and Prince Philip had the Duke of Edinburgh awards.
Geography graduate William has focussed on his passion for the environment, something he shares with his father and late grandfather.
In launching the prize, he said: "The plan is to really galvanise and bring together the best minds, the best possible solutions, to fixing and tackling some of the world’s greatest environmental challenges.
"We’ve got to harness our ingenuity and our ability to invent. The next 10 years are a critical decade for change.
"Time is of the essence, which is why we believe that this very ambitious global prize is the only way forward."
He spent two years putting it together before the launch.
He also said: "We believe that this decade is one of the most crucial decades for the environment and by 2030 we really hope to have made huge strides in fixing some of the biggest problems the Earth faces."
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