From the Grand Canyon to the California coast, Meenakshi Moorthy and Vishnu Viswanath documented a life of travel and and natural beauty in their adopted homeland for more than 10,000 Instagram followers.

The pair had immigrated to Silicon Valley from India. Moorthy described herself as the “high-spirited storyteller” who penned their social-media entries. Viswanath, she said, was the “head photographer of our most pretty pics”. Posting online was about more than just receiving “likes”, she often remarked. And she warned about the dangers of scaling high places just for photographs.

Last week, the couple’s bodies were discovered after tourists came across their abandoned camera equipment at the top of Taft Point, a granite outcropping 1,000 feet above the floor of Yosemite Valley. It is unclear whether the couple died while taking a selfie, as has been reported – though it would not be the first time that has happened in the park.

Although in posts Moorthy described herself as “a fan of daredevilry” and an “adrenaline junky”, friends and family said the married couple were usually very cautious.

“A lot of us including yours truly is a fan of daredevilry attempts of standing at the edge of cliffs and skyscrapers, but did you know that wind gusts can be FATAL???” Moorthy wrote on a post with a photo of her sitting on a cliff overlooking the Grand Canyon. “Is our life just worth one photo?”

‘He was the kind of person who could have changed the world’

Viswanath and Moorthy met while they were both studying in the western Indian state of Kerala. Viswanath had wanted to be a doctor or an engineer. “He used to be a chess player and loved maths,” his brother Jishnu remembers.

Like so many young Indians, Vishnu was drawn to software engineering – and the promise it held of a lucrative career overseas. After graduating, he and Moorthy, by then his girlfriend, moved to Illinois so that he could study at Bradley University.

Chris Nikolopoulos, a professor there, instructed Viswanath in artificial intelligence and later hired him as a research assistant. He said Viswanath was one of the brightest young programmers he had encountered in 30 years of teaching. “He had a very dynamic personality and a very active mind,” Nikolopoulos said. “He was the kind of person who could have changed the world.”

An expert in big data and AI, Viswanath had recently landed a job at Cisco. A friend, Mageshwaran Mohan, said that since Moorthy wasn’t permitted to work after accompanying Viswanath to the US, she threw her energy into blogging.

The couple launched their latest blog and Instagram account, titled Holidays and Happily Ever Afters, last year, describing it as: “The happy place where wishful wanderlust meets vistas of positivity.” Moorthy’s effusively upbeat posts, sprinkled with happy face emojis, rainbows and unicorn references, were complemented by Viswanath’s colorful photographs, in which Moorthy was unmistakable thanks to her bright pink hair.

One friend, Ameena Badarudeen, said that Moorthy had written to her: “The world has soooo many beautiful places out there and I feel we have soo little time to see them all.”

While Moorthy posted about the wonders of discovering new places, she also acknowledged the difficulties of the couple’s mobile lifestyle. She mentioned the hardships of finding an apartment in New York and then packing all the couple’s boxes for the move to California.

Sometimes she stopped posting for months, then mentioned the dark times she had experienced, and promoted an internet campaign to “#stopthestigma” of mental illness. “There are days in my life...when unicorns sparkling in rainbow glitter are dancing around me and still I am buried in my blanket for weeks together hurting in a whirl of hopeless dark thoughts,” she wrote.

Their friend Mohan said that, despite the ups and downs that come with immigrating to a new country, the couple felt like they were living a dream. “They were loving what they were doing,” he said. “She loved the fall colors and the snow, which we had never seen before in India. Even I am sad sometimes because I can’t go back and see my parents. But they were happy.”

The circumstances of their death are under investigation. Sean Matteson, a visitor who was at Taft Point on the night of the couple’s deaths, realized that he had unintentionally captured Moorthy in a photo he took of himself and a friend. She appeared to be closer to the edge than any other tourist.

Initially Viswanath’s brother, Jishnu, was widely reported to have said that the couple were taking a selfie when they died. But in an interview with the Guardian this week he said that was not strictly true. They had set up a camera separately, he said; he had not meant to imply that the couple fell as they were holding up a camera in their hands.

The danger of national parks

In any event, selfies have been blamed for numerous deaths in Yosemite. In September, an 18-year-old Israeli man, Tomer Frankfurter, fell from a 800ft cliff and died while taking one. In 2011, three young people died while trying to get pictures of Yosemite’s Vernal Falls.

A recent study documented 259 deaths worldwide caused by people taking selfies – dubbed “selficides” by the researchers – between October 2011 and November 2017. The vast majority of victims were young people aged 10 to 29. The most common causes of death were drowning, transport accidents and falls from high places.

The deaths of Viswanath and Moorthy pierce the benign image of US national parks, which remain wild and sometimes unforgiving places despite their record popularity. According to a 2017 analysis by Outside magazine, just over 1,000 people died in US national parks between 2006 and 2016, excluding suicides.

“People might be deciding, ‘Do I want to go to DisneyWorld or on a cruise or to a national park?’” said Graham Ottley, the general manager of Southern Yosemite Mountain Guides, a private guiding company. And, for people who are used to being in very regulated settings with guard rails and smooth pathways, “it may not be clear what is a safe place and what is an unsafe place”.

For those close to the couple, recent events still have an air of unreality. Nikolopoulos, the professor, said that “it is hard to believe” Viswanath died over something as trivial as a photograph. “They are still investigating, but who knows what happened. Maybe a deer or a bear came along.” He is looking into starting a scholarship program for graduate students in Viswanath’s name.

Jishnu, Viswanath’s brother, said that Viswanath and Moorthy had been planning to return to India at the start of next year for a wedding. He remembers his brother as “an amazing person, almost perfect in every aspect”. And he remembers the bond the couple shared. “They loved each other like no one has loved anyone else.”

• This story was co-published with the San Francisco Chronicle and High Country News.