It was a reaction felt keenly not only by ardent fans who grew up idolising the co-star of Grease for her turn in the film as Sandy.

The nationwide expressions of mourning and affection following her death showed Newton-John's legacy extended far beyond music into something even more personal and profound.

Her starring role in the 1978 hit musical, and her chart toppers, brought her to international fame and made her a household name. It was her own qualities of personal kindness and humility, her lack of pretension, that deepened her relationship with the nation from one of fleeting, casual fandom into genuine lifelong admiration and fondness.

One element of Newton-John's cultural impact has grown less visible as Hollywood has welcomed more Australian stars since she first starred opposite John Travolta in Grease. In 1978, Australians saw an Australian actress, speaking in an Australian accent, play a leading role in a movie that helped define an era and became a cultural landmark.

It was something new for the country, and in that way, Newton-John's success blazed a trail for Australian stars that followed her to the United States. For decades afterwards, she kept a lead role in Australia's cultural pantheon, one she performed with grace and generosity. It was a position that brought her onto the stage, along with John Farnham, to perform a duet opening the Sydney Olympics.

As Sandy in Grease, Newton-John was beautiful, feminine, strong and powerful all at once. It made her a hero for generations of Australian children afterwards, who grew up watching the film and playing its soundtrack at dances, parties, and dinner tables, memorising the lyrics of "Summer Nights", "You're the One that I Want" and "Greased Lightning". These songs became the staples for sleepover movie nights and karaoke singalongs for schoolkids, and extended Newton-John's appeal well beyond the era in which she found her greatest commercial success.

Her musical success was considerable. She sold more than 100 million records and charted nearly 40 songs on the Billboard Hot 100 in a career spanning nearly five decades. Songs such as "Physical", and those from another of her films, Xanadu, made a significant cultural impact.

Just as important was her influence on the following generations of musicians. Kylie Minogue's tribute to Newton-John - with a photo showing the younger star looking up to her idol - was a testament to this.

The tributes that flowed for Newton-John spoke of the sense of "light" she brought, for a reason. Fans and admirers described her as a "beacon of hope", someone who exuded positive energy even despite her personal battles with breast cancer. Her courage battling the disease gave inspiration to people and families fighting cancer everywhere. She broadened her legacy by setting up the Olivia Newton-John Foundation Fund, which researches plant-based treatments for cancer, and a cancer research and wellness facility in Melbourne. These were marks of her positivity and courage. Her prominent advocacy for cancer research only further deepened the respect and affection with which she was regarded in Australia and abroad.

The loss of Newton-John will long be mourned, and for the same reasons, her life will long be celebrated.