Kirsty Young's castaway is the educationalist and writer, Sir Anthony Seldon.

Now Vice-Chancellor of Buckingham University, he was the Master of Wellington College. He has written, co-written and edited more than 30 books, including political biographies of Prime Ministers Churchill, Blair, Brown and Cameron.

He had to take his 'A' levels twice before going on to read PPE at Oxford and doing a PhD at the LSE, before embarking on his teaching career. His first headmaster job was at Brighton College and then he went onto be Master of Wellington College. During his tenure, the school became co-educational, set up partner schools in China, and introduced a more holistic approach to learning with happiness classes and stillness sessions added to the curriculum and in 2009 the state secondary Wellington Academy was founded in Wiltshire.

He is a fellow of the Royal Historical Society and of the Royal Society of Arts and in 2014 was knighted for services to education and modern political history.

Producer: Cathy Drysdale.

Kirsty Young's castaway is the Sky TV news correspondent Alex Crawford.

She's won the Royal Television Society's Journalist of the Year award an unprecedented four times - reporting from the world's worst war zones and hot spots.

She spent the first five years of her life in Nigeria, where her family survived two political coups. After childhood in Zambia and subsequently what was then Rhodesia, she came back to Britain as a teenager to go to boarding school and then got her first job as a trainee reporter on the Wokingham Times.

She's been shot at, arrested and interrogated. But it's a job she loves and is still passionate to do. For her, there should be no 'no-go' areas for journalists and journalism remains an essential pillar of freedom and democracy.

Producer: Sarah Taylor.

Kirsty Young's castaway is the writer Colm Toibin.

Best-known for his novels "Brooklyn" - now made into a film - "Nora Webster" and "The Master," he has been nominated for the Booker Prize three times.

Born in 1955 in Enniscorthy, County Wexford, the second youngest of five children, Colm's life changed suddenly when his father died after a long illness when he was twelve. He says he has been dealing with the trauma which resulted in his writing ever since. After attending St Peter's College in Wexford and University College Dublin, he spent three years in Barcelona teaching English before returning to Ireland. He worked as a journalist until his books began to get published.

He once told a class he was teaching that "you have to be a terrible monster to write. I said, 'Someone might have told you something they shouldn't have told you, and you have to be prepared to use it because it will make a great story. You have to use it even though the person is identifiable. If you can't do it then writing isn't for you. You've no right to be here. If there is any way I can help you get into law school then I will. Your morality will be more useful in a courtroom.'"

Producer: Christine Pawlowsky.

Kirsty Young's castaway this week is Patricia Greene.

For nearly sixty years she has played the role of Jill in Radio 4's The Archers which celebrates its 65th anniversary on January 1st 2016. Over the decades the storylines have followed her character through one marriage, four children and since 2010, widowhood.

Born in Derby in 1931, Paddy's love of acting began early on inspired by her father who was a keen amateur actor. As an only and independent child she was surrounded by the adult world and would often eavesdrop as she hid under the kitchen table. Her parents loved entertainment and would take her to the cinema every week to see Hollywood romances or comedies.

After attending a grammar school she went to the Central School of Speech and Drama in London in 1951. She wanted to be a classical actress, but then a phone call from the Archers production office changed her career path and she joined the cast initially on a six week contract in 1957. Her character Jill went onto marry the farmer Phil Archer, and is still there with a recent storyline seeing her return to Brookfield, the family farm.

Patricia has been married twice and was widowed in 1986. She was awarded an MBE in 2007.

Producer: Cathy Drysdale.

Kirsty Young's castaway is Chris Hadfield.

He was the first Canadian commander of the International Space Station and took part in three space missions spending a total of 166 days orbiting the Earth. He has spent over 14 hours doing two space walks.

He flew his first eight day mission into space in 1995 during which he visited the Russian space station Mir. In 2001 he paid his first visit to the International Space Station to help install Canadarm2, a robot arm helping to build the station which was launched three years previously. In 2012 he began his final five month stay in space on board the ISS. It was on this mission that his videos of life in space - including a film of him singing David Bowie's Space Oddity and accompanying himself on guitar - led to him enjoying a huge following on social media.

Chris was born in 1959 in Ontario, the second of five children: his father was a pilot and the family lived on a farm. He mapped out his future career aged nine when he watched Neil Armstrong become the first person to walk on the moon in 1969. In pursuit of his dream Chris first become an Air Cadet, then attended military college, becoming a fighter pilot and then a test pilot, as well as an aeronautical engineer. He finally achieved his ambition of becoming an astronaut in 1992.

He went onto become the Chief of Robotics at the NASA Astronaut Office and Chief of International Space Station Operations at the Johnson Space Centre in Houston, Texas. Following his final space mission, Chris retired from the Canadian Space Agency in July 2013. Amongst the awards he's received are the military Meritorious Service Cross, NASA's Exceptional Service Medal and the Queen's Diamond Jubilee Medal.

Producer: Cathy Drysdale.

Kirsty Young's castaway is Kylie Minogue.

With seven number ones and ten million singles sold in the UK, she is the third-biggest selling female artist in Britain and has sold around 70 million records worldwide.

Born in Melbourne in 1968, Kylie and her sister Dannii began their careers as child actors on Australian television. At 17, Kylie landed the role of Charlene Mitchell in the soap opera Neighbours and her on-screen wedding to Jason Donovan's character Scott Robinson was watched by twenty million people in the UK alone.

Her recording career began after she was spotted singing at a charity event in 1987. Within months she had released a cover version of "Locomotion" which became the biggest-selling Australian single of the decade. Following the single's success, her first hit with record producers Stock, Aitken and Waterman was "I Should Be So Lucky": her debut album sold seven million copies.

At the age of 21, a romance with INXS lead singer Michael Hutchence led to a change in her image. In 2000, inspired by 1970s disco and assisted by gold hot pants, her single "Spinning Around" became her first British number one for a decade. She also sang to an estimated global audience of 3.7 billion at the closing ceremony of the Sydney Olympics.

In May 2005 she was diagnosed with breast cancer: following treatment she resumed the tour 18 months later.

Producer: Cathy Drysdale.

Kirsty Young's castaway is the surgeon, author and former Reith lecturer, Atul Gawande.

A general and endocrine surgeon in Boston, he is professor in both the Department of Health Policy & Management at the Harvard School of Public Health and the Department of Surgery at Harvard Medical School.

Born in Brooklyn, he is the son of two doctors who came to the US to study medicine. After graduating from Stanford and studying Philosophy, Politics and Economics at Oxford, he embarked on a brief political career, working for Bill Clinton's presidential campaign and on his health and social policy in the White House following his election. When Clinton's health policy reform floundered, Atul returned to Harvard to finish the medical degree he'd started after Oxford.

During his surgical residency he began writing for the online magazine Slate and he's been writing for the New Yorker since 1998. His 2009 article "The Cost Conundrum" was cited by President Barack Obama during his attempt to get the healthcare reform legislation through Congress. Atul has published four books to date about the achievements, but also the limitations, of medicine.

In 2014 he presented the BBC's Reith Lectures, delivering a series of four talks titled The Future of Medicine.

Producer: Cathy Drysdale.

Kirsty Young's castaway this week is Sandi Toksvig.

Host of BBC Radio 4's News Quiz until June 2015, she is also a writer and comedian and recently entered the world of politics, helping to found the Women's Equality Party.

Her parents were both broadcasters: her mother worked as a studio manager and announcer before she married, her Danish father's job as a foreign correspondent took the family around the world. Sandi and her siblings spent much of their childhood in the United States and when she was "asked to leave" yet another American school, her parents sent her to boarding school in England. She soon decided to lose her strong American accent and went on to Cambridge, where she performed in the Footlights.

In addition to writing, her most recent acting role was in Call the Midwife and she continues to appear regularly on TV and radio shows as a panelist: she is to start as the next host of QI, taking over from Stephen Fry. She's also Chancellor of Portsmouth University.

Kirsty Young's castaway is filmmaker Gurinder Chadha.

Writer, director and producer behind the films Bend it like Beckham, Bhaji on the Beach and Bride and Prejudice, she began her career as a BBC news reporter.

She was born in Kenya to Sikh parents and grew up in Southall in West London. Her political awakening came in her teens in the 1970s against the backdrop of the National Front and race riots in the capital. The bands she listened to, including the Clash, the Jam and the Specials, were fixtures at the Rock Against Racism concerts which galvanised her desire to make a difference.

Bend it Like Beckham, which launched the career of Keira Knightly, is now a hit musical on the West End stage. Her next film, Viceroy's House, tackles the Partition of India in 1947.

She was awarded an OBE in the 2006 Queen's Birthday Honours List for her services to the British Film Industry.

Producer: Paula McGinley.

Kirsty Young's castaway is the Right Honourable Nicola Sturgeon, MSP.

Leader of the Scottish National Party (SNP) and the fifth First Minister of Scotland in the devolved era, she is the first woman to hold either post. The eldest of two daughters, she was brought up in Irvine and attended the local Dreghorn Primary School. A studious child, she was encouraged in her interest in current affairs by a teacher and joined the SNP aged 16. At 21, she was the youngest candidate in the 1992 General Election, contesting the safe Labour seat of Glasgow Shettleston.

She learned a lot about electoral defeat in those first years, but after several unsuccessful attempts, she was elected to the Scottish Parliament as a list MSP for Glasgow in 1999. She served as the party's shadow minister for education, and later for health and for justice and was elected deputy leader of her party in 2004, standing on a joint ticket with Alex Salmond. When the SNP won the highest number of seats in the 2007 election, she was appointed deputy First Minister. She also took on responsibility for the SNP's independence referendum campaign.

In November 2014, following the No vote in the Scottish independence referendum and the subsequent resignation of Alex Salmond, Sturgeon was elected leader of the SNP and became First Minister of Scotland. She's been awarded the Scottish Politician of the Year award three times and in 2015 was judged to be the Most Influential Woman in the UK by BBC Radio 4's Woman's Hour.

She is married to Peter Murrell, Chief Executive of the SNP.

Producer: Cathy Drysdale.