Greetings From the World of Tomorrow — It's Today in Science Fiction

Today, on April 15, in 1726, English antiquarian William Stukeley visited Sir Isaac Newton, a day he would recall after Newton's death in his 1752 book, Memoirs of Sir Isaac Newton's Life. They discussed retirement together. After dinner, they went out into the garden for tea and sat under some apple trees.

"He told me, he was just in the same situation, as when formerly, the notion of gravitation came into his mind. 'Why should that apple always descend perpendicularly to the ground,' thought he to himself," Stukeley recounts. "'Why should it not go sideways, or upwards? But constantly to the earth's centre? Assuredly, the reason is, that the Earth draws it. There must be a drawing power in matter.'"

The famous story of Newton and the fallen apple was first described by Voltaire in an essay on poetry, in a fashion that may have led many to believe it was apocryphal. But in actuality, the story of the apple inspiring the theory of gravitation was one Newton told repeatedly throughout his life. Alongside the three laws of motion also described in his Principia, Newton's law of universal gravitation led to estimates of the mass of planets and validated the principles of planetary orbits laid out by Johannes Kepler decades earlier.

Data (Brent Spiner) plays poker with holographic projections of Isaac Newton (John Neville), Albert Einstein (Jim Norton) and Stephen Hawking (himself) in the 'Star Trek: The Next Generation' episode "Descent." CBS Television Distribution

In laying the groundwork for understanding our solar system, Newton became a scientific icon and, centuries later, a science-fiction staple. He has appeared in three episodes of Star Trek, at one time playing poker with Data (Brent Spiner) and Stephen Hawking (as himself). In an episode of Star Trek: Voyager, we learn that it was a member of the Q continuum who shook the apple tree and inspired Newton. Newton has also popped up in Doctor Who.

While Newton and his apple embody a certain scientific legitimacy and spirit of inquiry in science fiction, another April 15 anniversary reminds us of the genre's more populist realities. Science-fiction conventioneer, collector and critic Sam Moskowitz died on this day in 1997.

An instrumental figure in early science-fiction conventions, Moskowitz was also a historian of the sci-fi community, authoring The Immortal Storm: A History of Science Fiction Fandom in 1954. Culminating with the first World Science Fiction Convention (or Worldcon) in 1939, Moskowitz's book cataloged the community and its conflicts in great detail, right down to the wedge that split the Greater New York Science Fiction Club into the Marxist "Futurians" and Moskowitz's Queens Science Fiction Club.

While sometimes hung up on petty grievances and internecine warfare between factions of science-fiction nerds, Moskowitz is a major reason why such a thorough history of science fiction and its attendant fandom remains with us today. His books Explorers of the Infinite and Seekers of Tomorrow further detailed the genre's early decades through capsule biographies of some of its most prominent authors, including Olaf Stapledon, Jack Williamson, L. Sprague de Camp, Clifford D. Simak, Fritz Leiber and Henry Kuttner.

April 15 is also important in science-fiction fandom for another reason, marking the anniversary of the first poll of the all-time best science-fiction and fantasy novel by Locus magazine. In 1975, Locus readers named Frank Herbert's Dune the best all-time science-fiction and fantasy novel, securing its reputation just as lists put out by the American Film Institute and British magazine Sight & Sound secured Citizen Kane's as "the greatest film ever made." (Speaking of film, there's a new adaptation of Dune in the works and set for release later this year, directed by Arrival auteur Denis Villeneuve.)

This is Arrakis, the world of #Dune. @DuneMovie

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— Hans Zimmer (@HansZimmer) April 14, 2020

Published on this day 45 years ago, the Locus list's top 10 was rounded out with Arthur C. Clarke's Childhood's End, Ursula K. Le Guin's The Left Hand of Darkness, Robert Heinlein's Stranger in a Strange Land, Walter Miller's A Canticle for Leibowitz, Isaac Asimov's The Foundation Trilogy, Alfred Bester's The Stars My Destination, Heinlein's The Moon Is a Harsh Mistress, Theodore Sturgeon's More Than Human and Roger Zelazny's Lord of Light.

Science-fiction TV episodes aired on this date include The X-Files episode "Darkness Falls" (in 1994), Star Trek: Voyager's "The Omega Directive" (1998) and an episode of Star Trek: Deep Space Nine often regarded as one of the series' best, "In the Pale Moonlight" (also in 1998).