Once upon a time you couldn't just ask Siri or Alexa (or whichever virtual assistant you're into) to tell you if you should put on a raincoat or wear a sweater before leaving the house. Weather forecasting was not invented until the 1860s, a period when scientists like James Glaisher were taking off in hot air balloons to make discoveries about the universe. That's what The Aeronauts, starring Eddie Redmayne and Felicity Jones is all about.

Redmayne and Jones teamed up previously in the 2014 biopic The Theory of Everything, playing Stephen Hawking and his wife Jane Wilde. They both got Oscar nominations for their efforts, with Redmayne ultimately winning. This time, they are doing the biopic thing together once again, with Redmayne starring as James Glaisher, a real-life English meteorologist and aeronaut, who took flight in a hot air balloon on September 5, 1862 and reached heights of 38,999 feet, breaking the world flight altitude record at the time. Jones plays Amelia Wren, a composite character influenced by real-life scientists and aeronauts such as Amelia Earhart, Sophie Blanchard, and Margaret Graham. Together, they take flight in a gas balloon to fly it higher than it has ever been, and make scientific discoveries that could improve the lives of thousands of people.

However, the real flight that took place in 1862 did not involve a woman on board. Glaisher was joined by Henry Coxwell, another English aeronaut, for the historic journey into the clouds. Coxwell is not depicted in the film. The trailer also mentions the invention of weather forecasting technology in its first few moments, but weather forecasting was not invented by Glaisher, nor was it invented by Coxwell. Francis Beaufort and Robert FitzRoy are credited with the invention of modern methods of weather forecasting. The Aeronauts gives a composite portrayal of this moment in history.

The film will have its world premiere on September 8 at the Toronto International Film Festival, 157 years after the historic hot air balloon flight the movie's plot is based on, will get a theatrical release on December 6, and will be available to stream on Amazon Prime Video on December 20.

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