The Riddle of EnigmaYears of exacting study were coming to an end. All five student scientists, each the best its species had to offer, were one step away from their final degrees. One examination remained:...

Moon dust that comes alive in an attempt to destroy the invaders from Earth . . .A diabolical snare set on a fiery star for a desperate inter-galactic fugitive . . . An alien 'primitive' life form that...

As the planet gleamed in his viewport, Sallman Ken could not believe that such a bleak and icy globe could have produced intelligent life. Yet when the expedition had sent in unmanned landers, that was...

Light on Bottom...The light was artificial. Believe it if you can. I realise that for a normal person it's hard. Wasting watts to light up the outdoors is bad enough. Spending the world's limited power...

Shrouded in eternal gloom by its own thick atmosphere, Tenebra was a hostile planet: a place of crushing gravity, 370-degree temperatures, a constantly shifting crust and giant drifting raindrops. Uncompromising...

The return of BarlennanDhrawn was a giant rockball, more than 3,000 times the mass of Earth. Perhaps a planet, perhaps a nearly dead star, the 17 billion square miles of mystery cried out for investigation....

With degrees in astronomy, chemistry and education, it should come as no surprise that Harry Clement Stubbs - better known to SF readers as Hal Clement - produced some of the field's most compelling,...

Stranded on an alien planet, light years from home, wandering from blistering heat to searing cold, Nils Kruger was not a happy man. So when he met another being - even though it wasn't human - things...

In the very far future, when the oxygen in Earth's atmosphere has combined with the nitrogen . . .When the formerly life-giving seas are now formed of nitric acid . . .When the very atmosphere itself...

Kainui is one of a pair of double planets circling a pair of binary stars. Mike Hoani has come there to study the languarge of the colonists. But Kainui is an ocean planet, covered in water 1700 miles...

THE HARD-CORE SCIENCE OF HAL CLEMENTThe supreme practitioner of "hard" science fiction, Hal Clement combines ingenious problem-solving with suspenseful drama and action. These ten stories show the mastery...

Mercury had no atmosphere - everyone knew that. Why was it developing one now? An incredibly pulse-poounding science fiction story by one of the greatest science fiction storytellers of all time, Hal...

Mesklin is a vast, inhospitable, disc-shaped planet, so cold that its oceans are liquid methane and its snows are frozen ammonia. It is a world spinning dizzyingly, a world where gravity can be a crushing...

Hal Clement, one of the all-time greats of science fiction, was defining hard science fiction before such distinctions were even being thought of.  He once described his approach to writing: "[T]he rules...

About two centuries from now, the human race on Earth is in trouble, perhaps even facing extinction, because of the rapid evolution of diseases.A crew of young men and women travel to the moons of Saturn,...

Two ships race in from outer space and crash in the Pacific Ocean. One contains a hunter, entrusted with a vital mission. The other, his quarry - corrupt, evil, a criminal from an unearthly civilisation...

Time was running out for Bob Kinnaird. Without much warning, the Hunter - the green protoplasmic alien that lived inside him and cured all his ills - had suddenly become his destroyer. Day by day Bob...

A team of scientists are sent to Mercury aboard the Albireo to find out why it's developing an atmosphere. A series of events force the scientists out of their ship and onto the surface of Mercury, where...

La question de la vie extraterrestre est l’une des plus abstraites et fondamentales qui soit. Abstraite, faute d’exemple d’une telle vie. Fondamentale, car touchant à notre place au sein du cosmos, au...