The Queen’s resolve was not lost on the 500,000 people watching the Diamond Jubilee concert outside Buckingham Palace, who gave her a deafening reception as she entered without her consort by her side.

If her mood was at all sombre, it did not show as she beamed at the crowds, wearing a glittering gold cocktail dress adorned with Swarovski crystals that caught the last of the evening’s sunlight as she parted a black cape worn over it and waved to the crowd.

She made her entrance at 9pm, opting not to sit through pop acts such as Will.i.am and JLS, but also missing the tenor Alfie Boe, the opera singer Renée Fleming and the concert pianist Lang Lang, three of the acts most to her taste.

Buckingham Palace aides said that the Queen had always intended to arrive at that time, and that her late arrival was not connected to the Duke’s illness.

Her thoughts may have been elsewhere as she watched the second half of the concert, but she appeared to be enjoying herself nonetheless as the show reached its climax with an unforgettable performance by Madness from the roof of Buckingham Palace.

Once the concert was over, she lit the last in a chain of more than 4,000 Jubilee beacons burning around the world in celebration of her reign. The Duke, who will be 91 on Sunday, was spending the night at King Edward VII Hospital in London after being taken there by ambulance from Windsor Castle yesterday afternoon.

He was diagnosed with a bladder infection, which doctors said might have been brought on by the four hours he spent outdoors in cold and wet conditions during the Thames Diamond Jubilee Pageant on Sunday.

He will spend several more days in hospital, meaning he will miss today’s climax of the Jubilee celebrations, which will include a Service of Thanksgiving for the Queen at St Paul’s Cathedral. Buckingham Palace said he was “disappointed” to be absent and his illness will inevitably cast a shadow over today’s events.

Sir Elton John gently poked fun at the Duke before going on stage to perform.

“He hates pop music anyway so it’s probably a ruse on his part – anything to get out of a pop concert! But I hope he’s OK.”

Sir Paul McCartney, who was due to close the show, said: “I hope he’s OK. We all send him our best wishes for a speedy recovery.”

The Royal family will be concerned by the Duke’s latest bout of ill health, which follows an operation to clear blocked arteries and implant stents which kept him in hospital for four days over Christmas, but they are past masters at ploughing on regardless.

Dickie Arbiter, the Queen’s former press secretary, said of the Duke’s illness: “The Queen will cope without him. The show must go on as far as she is concerned.”

In stark contrast to Sunday’s atrocious weather, the clouds parted to bathe London in glorious sunshine in time for the concert to begin at 7.30pm.

In a perfectly-pitched combination of pomp, pageantry and pop, the Coldstream Guards were given the honour of opening the concert with a rousing drum roll and trumpet fanfare, parting to reveal rock’s ultimate showman, Robbie Williams.

The trumpeters moved seamlessly from military music to the opening bars of Let Me Entertain You as Williams, dressed in his own version of a guards uniform, treated the crowd to his signature tune.

The Duke and Duchess of Cambridge and Prince Harry, who were due to hold a party for the performers in Buckingham Palace following the concert, roared their appreciation from the royal box.

The Duchess, who mixed high street and designer fashion by wearing a blue and purple Whistles dress under a blazer by Alexander McQueen, sang along as Sir Paul McCartney,

Sir Elton John, Sir Cliff Richard and Kylie Minogue belted out a non-stop diet of crowd-pleasers.

As Sir Tom Jones sang Delilah, the Duke and Duchess and Prince Harry sang along lustily while waving union flags. The Countess of Wessex even danced in her seat as Will.i.am took the stage with Jessie J.

Meanwhile, Jessie J found a new fan in the Duchess of Cornwall, who leaned over to the Prince of Wales and said: “She is good!” Sadly, television cameras did not pick out her reaction to the sight of Grace Jones, in a giant shell-like red headdress and PVC bodice, singing her entire set while keeping a hula hoop twirling around her waist, or Annie Lennox performing with angel’s wings strapped to her back.

The spectacular setting for the concert was a triumph. The Queen Victoria Memorial, usually nothing more than a camera platform on major royal occasions, was transformed into a 360-degree rock arena, complete with an ingenious Perspex roof that sheltered the performers like the petals of a giant flower. The illuminated Palace formed the perfect backdrop.

Whether the setting would have been the first choice of the organisers is another matter: 10 years ago the Golden Jubilee concert was held in the far more contained environs of the Buckingham Palace garden, but on that occasion, when Sir Paul McCartney asked: “Are we doing this next year?” The Queen replied: “Not in my garden.”

For the younger members of the Royal family, the thousands lucky enough to get a ticket and 500,000 watching on giant screens in The Mall this was undoubtedly the highlight of the Jubilee weekend.

But it probably doesn’t stray too far into lese majeste to speculate that for the Queen herself, the concert would almost certainly have been the least enjoyable part of her Jubilee celebrations, even without the worry of the Duke’s health problems. After Saturday’s Derby — one of the Queen’s favourite days in any year — and the spectacle of Sunday’s River Pageant, a night in the presence of Cheryl Cole is unlikely to make into her Top 10 royal engagements.

Whether the Queen could even hear much of the Diamond Jubilee Concert is debatable: she is thought to have worn a discreet pair of ear-plugs, as she did for the Golden Jubilee concert in 2002.

But this was always intended to be primarily a night for the public to enjoy.

The 18,000 guests seated around the stage, of whom 10,000 had been selected from a public ballot, made the most of the dry, if cool, weather to dance in their seats as Madness sang Our House from the roof of the Palace and Stevie Wonder, Ed Sheeran and of course the concert organiser, Gary Barlow, ran though some of the biggest hits of the Queen’s 60 years.

Barlow said the Queen “absolutely” had input into the artists performing at the Jubilee concert tonight.

He added: “The whole Royal family household have had requests and people they want to see. What we’ve tried to do it is pick artists that span right across her reign – someone from every decade. We’re hoping for a really momentous occasion.” Sir Cliff Richard used his allotted six minutes to sing a hit from each of the six decades of the Queen’s reign, finishing with his Eurovision hit, Congratulations, and saying: “I wrote this song in 1968, but I’m sure it was meant to be performed tonight.”

In the concert programme, the Queen thanked artists who had come from Kenya, Australia and the US for coming to London to perform on what she said would be a “very memorable occasion”.

Her final duty of the day was to perform a ceremony to light the last of 4,200 Jubilee beacons burning from Tonga to Canada, including a line of 60 across Hadrian’s Wall and one on each of the highest peaks in England, Scotland, Wales and Northern Ireland.

Bruno Peek, the pageant master of the beacons, presented the Queen with a cut glass “diamond”, thanking her on behalf of “the nation, the Commonwealth, her realms and territories”.

The Queen placed the “diamond” in a wooden cradle, triggering a mechanism to light a beacon in The Mall which shot flames 15ft into the air.

Earlier in the day, 10,000 members of the public selected through a ballot had attended a picnic in the garden of Buckingham Palace, where they were treated to hampers prepared by the chef Heston Blumenthal and mingled with members of the Royal family including the Earl of Wessex.

Their tickets also gave them entry to the evening’s concert, but for others, the chance to watch it had been earned through the traditional endurance test on royal occasions: camping for two nights on a pavement in pelting rain.

By noon, The Mall was filling up with families by the time the concert began people were standing shoulder-to-shoulder down its entire length.

At 5pm, news of the Duke’s hospitalisation rippled through the crowd after it was announced by Buckingham Palace.

Craig Holdcroft, 37, a customer advisor from Stoke-on-Trent, said: “When I heard the news, I thought it was a joke. It’s devastating news. I just don’t know how things will go on now. The Queen would want us to carry on but tomorrow will probably be a bit more sombre.

“He was ill, of course, at Christmas and the whole of Britain and the Commonwealth just wish him the best.”

Sue Evans, 58, from Sutton, Surrey, said: “I’m very sorry to hear about the Duke. It’s very unpleasant news, especially for someone of his age. Hopefully, it’s just a precaution but that’s likely to spoil the day for the Queen.”

Olwen Forster, 61, from Sunderland, said: “I thought he looked really healthy during the Pageant; he was smiling and I thought he had picked up a bit. I don’t know what effect it will have on the Queen if anything happened to him.”

Many of the Mall campers were intending to spend another night out in the cold for the final day of the Jubilee

celebrations, when the Queen and six other members of the Royal family will process to Buckingham Palace in State carriages before the obligatory balcony moment.

The bad news, though it will come as little surprise, is that the rain is forecast to return today, meaning (apart for another soaking for the crowds) that the Royal family may use enclosed carriages for a procession through London, restricting the public’s view.