Two hundred thousand feet up, things go horribly wrong. An experimental low-orbit spaceplane breaks up on reentry, falling to earth over a trail hundreds of miles long. And in its wake is the beginning of the most important mission in the history of spaceflight.

Here are tales of star-faring adventure, peril, and drama. Here are journeys into the mind-bending landscapes of virtual worlds and alternate realities. Here you'll also find stories of humanity's astounding future on Earth, on Mars, and in the solar system beyond - stories that always get the science right. And Bova's gathering of deeply realized, totally human characters are the heroic, brave, tricky, sometimes dastardly engineers, astronauts, corporate magnates, politicians, and scientists who will make these futures possible.

Welcome to Ringworld, an intermediate step between Dyson Spheres and planets. The gravitational force created by a rotation on its axis of 770 miles per second means no need for a roof. Walls 1,000 miles high at each rim will let in the sun and prevent much air from escaping. Larry Niven's novel, Ringworld, is the winner of the 1970 Hugo Award for Best Novel, the 1970 Nebula Award for Best Novel, and the 1972 Ditmars, an Australian award for Best International Science Fiction.

Earth is an old planet, and her teeming masses are running out of resources - and time. It is up to men such as Jeff Holman to discover a haven for Earth’s millions. Altair VI is one such planet, and Holman is determined to transform this world into one where the human race can survive. Star probes long ago informed Earth that Altair VI had a flourishing ecology with one very tough beast at the top of the food chain, one that will have to be dealt with before the human colony ships arrive. The beast is not only tough, it is as smart as a man. Holman is faced with a soul-wrenching decision - for to make Altair VI habitable for humans, all native life must die.

Stoner knew. The fiery object hurtling toward the Earth was an alien spacecraft. But the world might never know. He was trapped in an iron cordon of secrecy, for the discovery had shattered the world power balance, setting off a brutal struggle for supremacy that raged from the sacred halls of the Vatican to the corridors of the Kremlin and the Pentagon. The forces of fear and treachery would use any weapon at their command, from mind war to sabotage, to keep the world in darkness.

A hero without peer or scruples, Sam Gunn has a nose for trouble, money, and women, though not necessarily in that order. A man with the ego (and stature) of a Napoleon, the business acumen of a P. T. Barnum, and the raging hormones of a teenage boy, Sam is the finest astronaut NASA ever trained and dumped. But more than money, more than women, Sam Gunn loves justice—and he really does love money and women.

The time: 200 years after man's first landing on the Moon. There are permanent populations established on the Moon, Venus, and Mars. Outer space inhabitants have formed a new political entity, the Federation, and between the Federation and Earth a growing rivalry has developed. Earthlight is the story of this emerging conflict.

When Kell and his team return to Earth many years after their departure, they find that their world has changed almost beyond recognition. Not only has a second wave of greenhouse flooding caused sea levels to rise, but society has been changed by the consequences of the climate shift. Few people want to face Jordan Kell's news. He must convince Earth's new rulers that the human race is in danger of extinction unless it acts to forestall the death wave coming from the galaxy's heart.

Vannemar Morgan's dream is to link Earth to the stars with the greatest engineering feat of all time: a 24,000-mile-high space elevator. But first he must solve a million technical, political, and economic problems while allaying the wrath of God. For the only possible site on the planet for Morgans Orbital Tower is the monastery atop the Sacred Mountain of Sri Kanda.

Deadly radiation from a passing comet is about to destroy life on Earth. In desperation, the US government constructs a series of underground shelters to protect as many people as possible. They are expected to be underground for 20 years before returning back to the surface. But can they survive their time within the confines of the underground shelter? And what will they find when they finally emerge?

Ghost ship Impris, lost during the War of a Thousand Suns, is the stuff of legend. Her very name conjures the perils of interstellar travel. But no mere legend, she is real - glimpsed on occasion in the hyperdimensional Flux and then gone. Her passengers and crew live on in a strange limbo, their fate hopelessly caught up in quantum defects in space-time, interstellar piracy, and galactic coverup.

Car-En, a ringstation anthropologist on her first Earth field assignment, observes a Viking-like village in the Harz mountains. As Car-En secretly observes the Happdal villagers, she begins to see them as more than research subjects (especially Esper, a handsome bowhunter). When Esper’s sister is taken by an otherwordly sword-wielding white-haired man, she can no longer stand by as a passive witness. Knowing the decision might end her career, she cuts off communication with her advisor and pursues the abductor into the mountains.

The year is 1876. Warring Indian tribes still populate America's western territories, even as lawless gold-rush towns begin to mark the landscape. In much of the country, it is still illegal to espouse evolution. Against this backdrop two monomaniacal paleontologists pillage the Wild West, hunting for dinosaur fossils while surveilling, deceiving, and sabotaging each other in a rivalry that will come to be known as the Bone Wars.

Late in the 21st century, Earth receives what looks like an urgent plea for help from planet Proxima Centauri b in the closest star system to the Sun. Astrophysicists suspect a massive solar flare is about to destroy this heretofore-unknown civilization. Earth's space programs are unequipped to help, but an unscrupulous Russian billionaire launches a secret and highly-specialized spaceship to Proxima b, over four light-years away.

The starship Earthling, filled with thousands of hibernating colonists en route to a new world at Tau Ceti, is stranded beyond the solar system when the ship's three organic mental cores - disembodied human brains that control the vessel's functions - go insane. The emergency skeleton crew sees only one chance for survival: build an artificial consciousness in the Earthling's primary computer that can guide them to their destination - and hope it doesn't destroy the human race.

Emanuel Goldsmith, a famous poet, murdered eight people, then disappeared. Three people want to find him: an aspiring writer, an embittered scientist who wants to use him, and a policewoman who needs to put him in custody before the Selectors, a vigilante organization, get to him first.

On September 28th, a geologist working in Death Valley finds a mysterious new cinder cone in very well-mapped area. On October 1, the government of Australia announces the discovery of an enormous granite mountain. Like the cinder cone, it wasn't there six months ago.

Something is happening to planet Earth, and the truth is too terrifying to contemplate

Roger Torraway watched in horror as the monster lurched, toppled over and died. Project Man Plus had gone suddenly and drastically wrong. The race to colonize Mars was too important, too costly, and America was already too committed, for plans to be scrapped. They would have to make a new Martian. And Roger Torraway was it, candidate for the endless surgery, operation after painful operation, that would enable him to survive on that faraway planet.

Humans call them Monument-Makers. An unknown race, they left stunning alien statues scattered on distant planets throughout the galaxy, encoded with strange inscriptions that defy translation. Searching for clues about the Monument-Makers, teams of 23rd century linguists, historians, engineers and archaeologists have been excavating the enigmatic alien ruins on a number of planets, uncovering strange, massive false cities made of solid rock. But their time is running out.

On June 30, 1908, an object fell from the sky, releasing more energy than a thousand Hiroshima bombs. A Siberian forest was flattened, but the strike left no significant crater. The anomaly came to be known as the Tunguska Event, and scientists have never agreed whether it was the largest meteor strike in recorded history - or something else. Alien artifacts have been uncovered since the 1908 event, and a new star drive is discovered.

The award-winning, bestselling author's first novel. The beamjacks work in zero-gravity constructing satellites in the vacuum of deepest space. And they're not going to let the military control them anymore.

After a hard day of labor in Thornheath, Leolin returns home, hoping to catch a glimpse of dragons flying by.

The very far future: The galaxy is a drifting wreck of black holes, neutron stars, and chill white dwarfs. The age of star formation is long past. Yet there is life here, feeding off the energies of the stellar remnants, and there is mind, a tremendous galaxy-spanning intelligence each of whose thoughts lasts a hundred thousand years. And this mind cradles memories of a long-gone age when a more compact universe was full of light... The 27th century: Proxima Centauri, an undistinguished red dwarf star, is the nearest star to our sun. How would it be to live on such a world?

The first interstellar ship, John Glenn, fled a solar system populated by rogue AIs and machine/human hybrids, threatened by too much nanotechnology, and rife with political dangers. The John Glenn’s crew intended to terraform the nearly pristine planet Ymir in hopes of creating a utopian society that will limit intelligent technology, but by some miscalculation they have landed in the wrong system.

They first appear as a series of dots on astronomical plates, heading from Saturn directly toward Earth. Since the ringed planet carries no life, scientists deduce the mysterious ship to be a visitor from another star. The world's frantic efforts to signal the aliens go unanswered. The first contact is hostile: the invaders blast a Soviet space station, seize the survivors, and then destroy every dam and installation on Earth with a hail of asteriods.

Matt Cruse is a cabin boy on the Aurora, a huge airship that sails hundreds of feet above the ocean. One night he meets a dying balloonist who speaks of beautiful creatures drifting through the skies. It is only after Matt meets the balloonist's granddaughter that he realizes that the man's ravings may, in fact, have been true, and that the creatures are completely real and utterly mysterious.

In the year 2031, a robot probe detects traces of biological activity on Enceladus, one of Saturn's moons. This sensational discovery shows that there is indeed evidence of extraterrestrial life. Fifteen years later, a hurriedly built spacecraft sets out on the long journey to the ringed planet and its moon. The international crew is not just facing a difficult twenty-seven months: if the spacecraft manages to make it to Enceladus without incident it must use a drillship to penetrate the kilometer-thick sheet of ice that entombs the moon.

Young Carmen Dula and her family are about to embark on the adventure of a lifetime - they're going to Mars. Once on the Red Planet, however, Carmen realizes things are not so different from Earth. There are chores to do, lessons to learn, and oppressive authority figures to rebel against.

The crime of the century begins without a hitch. On July 5th, 2070, as it's about to be launched, the starship Alabama is hijacked - by her captain and crew. In defiance of the repressive government of The United Republic of Earth, they replace her handpicked passengers with political dissidents and their families. These become Earth's first pioneers in the exploration of space...

The year is 2380. The Intersolar Commonwealth, a sphere of stars some 400 light-years in diameter, contains more than 600 worlds, interconnected by a web of transport "tunnels" known as wormholes. At the farthest edge of the Commonwealth, astronomer Dudley Bose observes the impossible: Over 1,000 light-years away, a star...vanishes. It does not go supernova. It does not collapse into a black hole. It simply disappears.