London: Climate scientist and former astronaut Piers Sellers passed away on Friday at the age of 61. He was suffering from pancreatic cancer.
British-born astronaut gained fame late in life for his eloquent commentary about the Earth's fragility.
Sellers had flew on three space shuttle missions between 2002 and 2010.
He even shared his astronaut's perspective on climate change in Leonardo DiCaprio's documentary, Before the Flood which was released earlier this year.
He told DiCaprio that seeing the earth's atmosphere as a "tiny little onion skin" from space helped him gain a fuller understanding of the planet's delicacy.
He also wrote a New York Times op-ed about grappling with the meaning of his life's work after learning he had terminal cancer, the Guardian said in its report.
In both the film and the op-ed, he was optimistic, arguing that he expected human ingenuity to rescue the planet from a dire future of runaway global warming.
NASA Administrator Charles Bolden described Sellers as "a tremendous public servant who was dedicated to Nasa, the nation and the world".
He was born in Crowborough, East Sussex and began working for the US space agency as a scientist in 1982 before joining its astronaut corps in 1996.
NASA said Sellers was diagnosed with stage four pancreatic cancer in 2015.
He became a naturalised US citizen in 1991, making him eligible for the space programme.
(With IANS inputs)