In 1930 astronomer Clyde Tombaugh made the discovery of a lifetime: the planet Pluto. His work remains relevant today as astronomers continue their search for planets in the outskirts of our solar system. This fascinating biography chronicles the life of one of the giants of 20th century astronomy.

The story of the young farm boy who became an astronomer and discovered the planet Pluto at the age of twenty-four.

An adventure in scientific discovery Pluto, the farthermost planet in the solar system, some 3,673 million mites from the Sun, was discovered by Clyde Tombaugh at the Lowell Observatory in 1930. The fiftieth anniversary of Pluto's discovery will be celebrated in 1980 and OUT OF THE DARKNESS: THE PLANET PLUTO tells the exciting scientific story of the twenty-five year search for a planet X beyond Neptune, and its discovery-the only planet found in the twentieth century. The planets Mercury, Venus. Mars, Jupiter, and Saturn were all known since antiquity. Then Sir William Herschel discovered Uranus in 1781, and 65 years later, in 1846, Johann Calle and Urbain le Verner discovered Neptune. Variations in orbital perturbations of the planets and theoretical astronomy were responsible for predicting and discovering the three outermost planets (Uranus, Neptune, and Pluto) and so Pluto's story is also, to some extent, the story of its planetary neighbors. What kind of world is Pluto? Much is still a mystery (its exact size, for instance), but there are some facts. It takes 247.7 years for Pluto to revolve around the sun. From Pluto's surface, the Sun appears as a star-like point; giving only on-one-hundredth the light Earth receives, although it is still brighter than a full Moon. There is strong evidence to suggest that Pluto is an escaped satellite of Neptune, a sister moon of Triton that wandered off to become the farthermost planet revolving around the Sun. And the recent discovery of Pluto’s moon, Charon, and the speculation on a tenth planet beyond Pluto add to the mystery that still prevails 50 years after coauthor Clyde Tombaugh exclaimed “That’s it!” when he saw the change of position of a faint object on the photographic plates after examining millions of star images. That evening, the only man alive to discover a planet, went to the movies and saw Gary Cooper in The Virginian. The night sky was cloudy when he came out of the theatre, but his mind’s eye still saw the faint image of Pluto.

Pluto looms large in Flagstaff, where residents and businesses alike take pride in their community's most enduring claim to fame: Clyde Tombaugh's 1930 discovery of Pluto at Lowell Observatory. Percival Lowell began searching for his theoretical "Planet X" in 1905, and Tombaugh's "eureka!" experience brought worldwide attention to the city and observatory. Ever since, area scientists have played leading roles in virtually every major Pluto-related discovery, from unknown moons to the existence of an atmosphere and the innovations of the New Horizons spacecraft. Lowell historian Kevin Schindler and astronomer Will Grundy guide you through the story of Pluto from postulation to exploration.

Discovering Pluto is an authoritative account of the exploration of Pluto and its moons, from the first inklings of tentative knowledge through the exciting discoveries made during the flyby of the NASA New Horizons research spacecraft in July 2015. Co-author Dale P. Cruikshank was a co-investigator on the New Horizons mission, while co-author William Sheehan is a noted historian of the Solar System. Telling the tale of Pluto’s discovery, the authors recount the grand story of our unfolding knowledge of the outer Solar System, from William Herschel’s serendipitous discovery of Uranus in 1781, to the mathematical prediction of Neptune’s existence, to Percival Lowell’s studies of the wayward motions of those giant planets leading to his prediction of another world farther out. Lowell’s efforts led to Clyde Tombaugh’s heroic search and discovery of Pluto—then a mere speck in the telescope—at Lowell Observatory in 1930. Pluto was finally recognized as the premier body in the Kuiper Belt, the so-called third zone of our Solar System. The first zone contains the terrestrial planets (Mercury through Mars) and the asteroid belt; the second, the gas-giant planets Jupiter through Neptune. The third zone, holding Pluto and the rest of the Kuiper Belt, is the largest and most populous region of the solar system. Now well beyond Pluto, New Horizons will continue to wend its lonely way through the galaxy, but it is still transmitting data, even today. Its ultimate legacy may be to inspire future generations to uncover more secrets of Pluto, the Solar System, and the Universe.

The New York Times bestseller: "You gotta read this. It is the most exciting book about Pluto you will ever read in your life." —Jon Stewart When the Rose Center for Earth and Space at the American Museum of Natural History reclassified Pluto as an icy comet, the New York Times proclaimed on page one, "Pluto Not a Planet? Only in New York." Immediately, the public, professionals, and press were choosing sides over Pluto's planethood. Pluto is entrenched in our cultural and emotional view of the cosmos, and Neil deGrasse Tyson, award-winning author and director of the Rose Center, is on a quest to discover why. He stood at the heart of the controversy over Pluto's demotion, and consequently Plutophiles have freely shared their opinions with him, including endless hate mail from third-graders. With his inimitable wit, Tyson delivers a minihistory of planets, describes the oversized characters of the people who study them, and recounts how America's favorite planet was ousted from the cosmic hub.

For five decades after its discovery in 1930, the planet Pluto remained an enigma. However, several events during the last two decades have helped to lift the veil of mystery surrounding the ninth planet. The discovery of its satellite, Charon, in 1978 permitted occultation observations that allowed scientists to determine the size of both bodies. Astronomers also detected the presence of an atmosphere, and the Hubble Space Telescope provided views in unprecedented detail. In addition to these two fortuitous events, advances in telescopic instrumentation and computational methods led to exciting observational and theoretical discoveries. This new Space Sciences Series volume focuses on the scientific issues associated with Pluto and Charon. Fifty collaborating authors here review the latest research on the Pluto-Charon binary, from bulk properties, surfaces and interiors to atmospheric structure, composition, and dynamics. They also provide historical perspectives on Pluto-Charon research and discuss the population of the trans-Neptunian region and the origin of the Pluto-Charon binary. Also included are prefatory remarks by Pluto's and Charon's discoverers, Clyde Tombaugh and James Christy. This volume offers the most comprehensive available compendium of research work for understanding these far off members of our solar system, just at a time following dramatic developments in our knowledge but before that knowledge can be advanced by spacecraft missions.