The first test of an orbital flight around the Moon is scheduled. During liftoff one of the stages does not separate correctly causing the ship to no longer be under control. A crew member goes outside the ship to inspect the damage. While outside an accident occurs that endangers both his life and that of the crew and ship
Four men in Moonship Alpha attempt the first Moon landing. The ship begins to topple after touchdown, forcing an emergency lift-off. A crew member, not in his acceleration-couch, is injured but conceals the fact.
When an experimental nuclear-powered missile goes out of control, its creator insists on accompanying McCauley into space to try and disarm it before it can strike the moon and wipe out a twelve-man expedition.
Trailblazer I is on route to the Moon when one of the crew gets word his wife has been hurt in a car wreck. Although distracted, the crewman needs to focus all his skills and abilities to overcome a major accident.
Shortly after leaving the Moon a spacecraft is hit by an asteroid destroying their oxygen supply. The three man crew now become engaged in a life and death battle to extend their oxygen supply long enough to make it home.
It is decided to conduct an experiment to see if women could handle the rigors of spaceflight and living on the Moon. The plan is to send a woman to the Moon for 90 days. Initially she doesn't cope very well through a lack of training or projects to complete. Eventually she comes up with a novel set of activities to try and show her value to the mission
It is decided to attempt fuel transfers between space craft while flying in orbit. The requirement for precision control of two spacecraft is met by using a pair of specially trained twins. Safety is the primary concern, but ensuring this, they overlook one potential fatal flaw in the mission
Col. McCauley is training a young cadet who wants to be an astronaut, and pushes the young man almost to his limit. When an onboard accident knocks out McCauley, the nervous young cadet has to bring the craft back to Earth on his own.
Four men a stranded after their spacecraft crash lands on the Moon. Their only hope of survival is to walk to Moonbase. All goes well till they realize the oxygen tank they are carrying to resupply themselves has a faulty valve. There is a way around the problem, but the cost may be too high for the team to accept
An eager, space-enthusiast technician installs a smaller Guidance Control System he designed into the rocket ship. There is now room in the equipment bay for him to stow away on the next flight. But during the 12G takeoff his improvised couch crushes the equipment rack, causing the ship to lose all power before reaching orbit. The uncontrollable ship will quickly re-enter and burn unless repairs can be completed.
A scientist's wife warns McCauley that her husband Perry's's co-worker Hal Carter is jealous of his success. McCauley doesn't believe her, but when Perry's theory about radioactive gas on the moon prove correct, Hal plots to kill Perry.
Tensions mount as final crew selections go forward for a special observation flight of the sun. At the core of the conflict is the potential for one of the crew to be a woman. The other candidates fail to treat her as a highly trained crew person and only see her as a vulnerable woman. Ultimately she uses her gender to solve the problem
Col McCauley, while serving on the space station gets word his son has been seriously injured in a hit and run accident near the rocket base. Tension mounts as word comes through the driver of the car has been identified, and appears to be on duty on board the space station. With nowhere to run and nowhere to hide on the station, how will this terrible emotional conundrum be resolved
While on a routine flight one of the rockets is hit by a meteor fragment. On Earth they run tests to discover the meteor is not only made of metal, but appears to have been artificially created. A second flight is launched immediately to retrieve more samples. What they discover may solve one of the greatest mysteries known to man
A series of photographs taken by an expedition on the Moon shows some sort of artificial object moving up on a ridge. Two men are sent to investigate; what they find amazes them. Then an accident leaves them in deadly danger.
Space station Astra is chosen for a medical experiment to measure men's reactions to stress and fatigue. The medical director is convinced he can quantify a person's reactions to strain and so prevent accidents. Then a life-threatening problem on the space station requires men to perform well beyond their limits. An inner "voice of infinity" is what they heard, enabling them to save the situation.
Colonel McCauley returns from Asteroid 78-1. The mission was cut short by the failure of his suit oxygen supply. He is insistent that just before he passed out he saw fossil evidence of life on the asteroid. Unconnected with this, Air Force medical staff have recommended his prolonged series of missions requires a 60-day 'grounding' to recover from stress. Will McCauley be able to lead the return mission to the asteroid if its unpredictable orbit permits another rendezvous?
A miss-fire of the MR28 sees the craft miss the Moon and head for deep space. The only chance of rescue is a new MX experimental rocket. In theory, the new ship should have the range. In practice, no one really knows.
A 3-man team visit the Lunar Observatory, isolated from all Earth signals on the Moon's far side, for routine Radio Telescope work. They pass the time during a long sky-mapping session by taping 'A glimpse of lunar life' sound-broadcast. An power fault interrupts and requires a Moon walk to the Radio Telescope. One man is badly injured while returning. Unconscious for days, he responds to the tape-recording and deliriously asks to hear the 'sound from the stars'. His colleagues comply and make an interesting discovery.
On the Moon the US and Soviets are in an informal race to be the first to Mars. Both sides play down the need to rush with concerns about safety. Ultimately both missions launch within minutes of each other, but a terrible accident completely changes the game and the ultimate fate of both crews
Ship MR34 loses Auto-Control during landing and crashes 200 miles from Moon Base. Two of the crew survive and make for a nearby fuel-cache. Can they use the liquid oxygen there to improvise a survival igloo?
A Soviet Major is the sole survivor of a crash landing near a US advance moon station. Determined to appear blameless, he reports Americans sabotaged the landing and then takes drastic action to destroy all evidence.
A new project involves launching capsules of atomic waste into orbit and then assembling them with an atomic rocket motor. The unit is then accelerated for disposal into the Sun. The civilian Project Engineer, who will attach the a-rocket in space, is a former astronaut who resigned after a re-entry accident. He now lacks confidence in himself and is convinced that no-one else trusts him.
Colonel McCauley is assigned to observe and assist the British space program. Their Vega Project will use a more powerful second-stage rocket engine. McCauley has to express the US concerns about the reliability of this engine.
The crew of MR37 encounter a strange object that they first believe is a meteor till it starts changing direction to match their ship. Whatever the object was it is confirmed it could not have come from Earth. When MR30 also encounters the object, a desperate chase begins to try and identify it
The first mission to Mars is nearing the red planet when a series of accidents and break downs put the mission in doubt. The crew must balance the need for caution and safety against the massive amount of scientific data that could be gained on such an expedition.