Why is the European Space Agency beaming a waltz at NASA's Voyager 1 probe this weekend?

With its sweeping tempo and ethereal melody, Austrian composer Johann Strauss II's "The Blue Danube" waltz has become synonymous with outer space and science fiction ever since it was chosen by Stanley Kubrick for 1968's "2001: A Space Odyssey."

Now "The Blue Danube" waltz with its whirling orbital rhythms will truly become the music of the cosmos when the European Space Agency broadcasts the lilting classical piece into deep space in celebration of the agency's 50th anniversary this year, in addition to the bicentennial of Johann Strauss II's birth in 1825.

Performed by the Wiener Symphoniker (Vienna Symphony Orchestra), this definitive anthem of space and sci-fi will be transmitted towards NASA's Voyager 1 probe by ESA's 35-meter Deep Space Antenna in Cebreros, Spain. Space fans and music lovers can watch an entire 15-minute livestream on the event's official website and on their YouTube or Instagram Channel regardless of your location, starting at 3:30 p.m. ET (1930 GMT) on Saturday (May 31).

Known in its native German as "An der schönen blauen Donau" which translates into "By the Beautiful Blue Danube," the beautiful composition's 13,743 notes are being broadcast into the interstellar void on a mission that "is both a tribute to the past and a testament to the future – a Viennese Waltz that will echo through space forever," according to the event's website.

Composed by Strauss in 1866 as a consolatory gift to the Viennese people after defeat in the Austro-Prussian War, "The Blue Danube" was conceived from a poem describing the Danube River by Karl Isidor Beck that contained the phrase "beautiful blue Danube."

It's one of the most widely recognized pieces of classical music in the world, partly due to its Hollywood history, its associations with space, and being a universally-loved audience favorite in concert halls around the globe.

In a pivotal transition scene from director Stanley Kubrick's magnum opus "2001: A Space Odyssey," the film cuts from a twirling bone during the dawn of early humans to an orbiting nuclear weapons platform in the future as the camera follows a needle-nosed Pan Am spaceship drifting towards a gently turning space station. The tune continues on as another shuttle docks at the Clavius moonbase built on the lunar surface.

Fans also might recall "The Blue Danube Waltz" being employed in an episode of "The Simpsons" where Homer opens a smuggled bag of potato chips ("Careful, they're ruffled!") inside a space shuttle and proceeds to catch floating chips in his mouth along to the swaying melody of the Strauss melody.

The King of Waltz's iconic musical masterpiece wasn't included in NASA's Voyager space probes' Golden Records launched into space back in 1977, but this Waltz into Space aimed at Voyager 1 will correct that glaring oversight.

Currently, Voyager 1 is traveling 15.4 billion miles (24.8 billion kilometers) from Earth, taking this celebratory signal roughly 23 hours and 3 minutes to reach the historic spacecraft.