based on some real, honest, practical ethical thinking. It is an idea book.' - Groff Conklin in Galaxy Science FictionAsher Sutton has been lost in deepest space for twenty years. Suddenly arrives a warning from the future, that he will return- and that he must be killed. He is destined to write a book whose message may lead to the death of millions in centuries to come. For this reason Sutton is hounded by the sinister warring factions of the future who wish to influence or prevent the writing of this book he has not yet begun to write.Yet already a copy has been found in the burnt-out wreckage of a space-craft on Aldebaran XII.

    Most victims die, others experience physical or psychic changes: aces have useful powers, deuces minor maybe entertaining abilities, jokers uglified, disabled, relegated to ghettos.

    Kirk is the youngest man to be promoted to the rank of captain in Federation history. His crew consists of a first officer who finds him impetuous; a chief engineer who finds him arrogent; a chief medical officer who finds him trifling; and a helmsman who wants a transfer. But the young crew, which would later become the legendary space explorers, quickly puts aside their differences when a monstrous starship appears on their nascent flight path.

    the desperate, take-no-prisoners struggle that led humanity to Halo--the fall of the planet Reach. Now, brought to life for the first time, here is the full story of that glorious, doomed conflict.While the brutal Covenant juggernaut sweeps inexorably through space, intent on wiping out humankind, only one stronghold remains--the planet Reach. Practically on Earth's doorstep, it is the last military fortress to defy the onslaught. But the personnel here have another, higher priority: to prevent the Covenant from discovering the location of Earth.Outnumbered and outgunned, the soldiers seem to have little chance against the Covenant, but Reach holds a closely guarded secret. It is the training ground for the very first "super soldiers." Code-named SPARTANs, these highly advanced warriors, specially bioengineered and technologically augmented, are the best in the universe--quiet, professional, and deadly.Now, as the ferocious Covenant attack begins, a handful of SPARTANs stand ready to wage ultimate war. They will kill, they will be destroyed, but they will never surrender. And at least one of them--the SPARTAN known as Master Chief--will live to fight another day on a mysterious and ancient, artificial world called Halo...

    The title is a play on words, one meaning "the force which pulls" & the other being "extremely serious or important". It was serialized in Astounding Science Fiction, 4–7/53. Its 1st cloth publication was in '54. It was 1st published in paper in '58. Along with the novel itself, many editions (& most recent editions) of the book also include Whirligig World, an essay on creating the planet Mesklin that was published in the 6/53 Astounding. He published two sequels, a '70 novel called Star Light & a '73 short story called Lecture Demonstration. Mission of Gravity was nominated for a Retro Hugo Award for '54.For a profit & adventure Barlennan would sail thousands of miles across uncharted waters, into regions where gravity played strange tricks. He'd dare the perils of strange tribes & stranger creatures--even dicker with those aliens from beyond the skies, though the concept of another world was unknown to the inhabitants of the planet of Mesklin. But in spite of the incredible technology of the strangers & without regard for their enormous size, Barlennan had the notion of turning the deal to an unsuspected advantage for himself--a considerable enterprise for a being very much resembling a 15" caterpillar!