Born in New South Wales, Australia, Captain Alan Carter was working on the Meta-Probe mission on Moonbase Alpha when the moon was hurled from Earth orbit ('Breakaway'). A top rate pilot, he was chosen to pilot a survival ship in the episode 'Black Sun' and has since survived more crashes and mishaps than any of his colleagues. He is a good-natured, friendly individual who is also fearless, dependable, and fiercely loyal to the Commander and his colleagues, as evident in both 'Missing Link' and 'Seed of Destruction'. Some of his leisurely pursuits include singing, athletics, keeping an eye on blondes and brunettes, and ridiculing Tony's home brew. He was briefly involved with his colleague Sandra Benes ('Full Circle') and later, with the beautiful Norvan, Sahala ('Dorzak').

Annette had only been married to Bill Fraser for two months when he was kidnapped by Maya's father Mentor. For a few hours, Annette followed the events on Psychon helplessly from Command Centre, her mood going from despair to hope and back again as Mentor menaced to drain her husband's intelligence for use in his biological computer. Fortunately, Maya's decision to free the Alphans on the planet saved Bill's life, and the couple were reunited. ('The Metamorph')

Even after 'Breakaway', it seems Moonbase Alpha continued to have its own broadcast team. Barbara gave the Zorefs a cheery wakeup call in the episode 'Force of Life'.

As one of Dr. Russell's junior colleagues, Ben's duties include assisting her in surgery and contributing to her research on the difficult medical situations which can arise on Alpha. In particular, he helped her design a replacement heart for Michelle Osgood ('Catacombs of the Moon'). Although he is subordinate to her, Ben does not hesitate to express his opinion if he doesn't agree with something Helena is doing; for instance, he was adamantly opposed to the idea of operating on Maya when she was affected by a feverish condition in 'Space Warp'. Before 'Breakaway', he was engaged to a young student nurse called Louisa. Years later, he was fooled into believing she had come to Alpha when a race of telepathic aliens invaded the Moonbase to drain its power supplies ('Bringers of Wonder').

When the evil Psychon Dorzak came to Alpha, he kidnapped Dr Russell in order to make her remove the implant that made the Croton Sahala immune to his hypnotic powers. Tony called upon Helena's assistant Ed Spencer to implant him with a device similar to Sahala's. Since this made Dorzak unable to control Tony, the latter was able to neutralise the Psychon and save Helena and Maya, who were both under his influence.

Born in Chicago, Illinois Helena Susan Russell was working for the Space Commission when she met and then married astronaut Lee Russell. Her husband was on the Astro 7 mission and was presumed dead when the ship was destroyed while in orbit around Jupiter, though it later turned out he had been changed into anti-matter on an alien planet ('Matter of Life and Death'). After his disappearance, Helena retreated into her work and joined the Space Service in 1992. She was part of the medical team who declared Tony Cellini unstable in 1996 ('Dragon's Domain') before becoming Chief Medical Officer on Moonbase Alpha.
Her hobbies include sculpting, a talent which she put to good use when the trader Taybor wanted a duplicate of Maya ('The Taybor'). Although she projects an image of serious professionalism in her work, Helena is a sensual, fun-loving woman off duty, who enjoys parties and even indulges in the occasional practical joke, as in 'The Exiles', where she dared the commander to tell the difference between her and Maya, who had taken her form. Helena's relationship with Commander John Koenig has blossomed since 'Breakaway' and they have enjoyed a stable romantic relationship since the early days of Alpha's adventure.

While still a child, in 1985, Jim Haines lost both parents to the Queller drive, a device designed to improve space travel, but which proved faulty and caused the death of 200 people. The Voyager probe, equipped with this engine, was allowed to wander out into space, where it caused further destruction to alien races, and eventually crossed the path of Alpha. Jim was devasted when he discovered that the man he was working with on Alpha was in fact Ernst Queller, inventor of the ill-fated device. When Queller destroyed the Voyager probe, killing himself in the process, Jim was left with the task of continuing his mentor's work as one of Alpha's main engineers.

Born in Brooklyn, New York, John Robert Koenig became the ninth Commander of Moonbase Alpha on September 9, 1999, shortly before a nuclear explosion propelled the moon out of Earth orbit ('Breakaway'). Prior to this assignment, John was an astronaut; he notably participated in the first manned mission to Venus. On that occasion, he was forced to abandon some of his colleagues, including two close friends, when they contracted the venusian plague -- an event which still haunted him years later ('The Lambda Factor'). At the beginning of the Nineties, John was assigned to Moonbase Alpha and collaborated with Victor Bergman and Tony Cellini on the failed Ultra Probe mission in 1996 ('Dragon's Domain'). John was suspended due to his support of Cellini, but eventually resumed his duties for the Lunar Science and Resea rch Organisation. Left to command a base of 311 survivors after Breakaway, John has had to lead his people through many more catastrophic adventures, from the Moon's passage through a black hole ('Black Sun') to attacks from far superior alien forces (as in 'The Dorcons').
His first wife Jean was killed during a conflict in 1987 ('The Rules of Luton'), but in his time on Alpha, John has become involved with the Chief Medical Officer, Dr. Helena Russell. Although as commander of the base, he tends to remain aloof from his colleagues, John has had amicable relations with most of his close subordinates; he played chess with David Kano, discussed philosophy with Victor Bergman, and joins in the general ribbing that accompanies each new batch of Tony Verdeschi's beer. Despite this friendly off-duty attitude, however, John Koenig is not a man to be trifled with. He can be given to violent displays of anger, particularly when the life of someone close to him is at stake (as David Kano found out to his detriment in 'The Last Sunset'). But another aspect of this passionate character is a p rofound determination to survive at all costs, and it seems unlikely the Alphans would have done as well as they did without Koenig's leadership.

Although she never got more than a couple of lines to speak, Operative Kate can be seen in the background in many Space:1999 episodes from both seasons. Her biggest on-screen role was in the second season episode 'The Taybor', where she attempted to trade a woollen jumper in exchange for some intergalactic treasures.

Maya first encountered the Alphans when the Moon drifted into the vicinity of her home world, Psychon. The planet was dying -- most people, including Maya's brother, had already left ('The Rules of Luton') -- but Maya's father Mentor hoped to revive it using his biological computer Psyche. Unbeknownst to Maya, Psyche fed on the brains of intelligent beings, and Mentor had taken to luring passing ships to Psychon in order to feed their occupants to the computer. This was the fate that awaited the Alphans until John Koenig told Maya what her father was doing and persuaded her to help them escape. Maya did free John; the commander destroyed Psyche, killing Mentor and causing the annihilation of the planet in the process. With nowhere to go, Maya joined the Alphans ('The Metamorph'). She believed herself to be the last of her species until Alpha unexpectedly came across the evil Dorza k, who used his mind-control powers to attempt to escape from his incarceration. This incident brought Maya to question the nature of her species ('Dorzak').
Highly intelligent and coming from a more advanced civilisation, Maya became the science officer on Alpha and was often able to use her knowledge of space and its inhabitants to protect her new home. Unused to human society, Maya was awkward in her early contacts with her colleagues, notably when geologist Dave Reilly tried to chat her up ('All That Glisters'), although she rapidly struck up a solid friendship with Helena ('The Exiles'). It didn't take Maya too long to adapt, however, and she was soon involved in a humorous, flirtatious relationship with Tony Verdeschi ('New Adam New Eve', 'The Beta Cloud'). This relationship took on a more serious aspect when Tony came close to death following an encounter on an alien planet; Maya chose to leave Alpha to join him even though there was no guarantee she could return. Fortunately, the alien who had accidentally injured Tony proved benevolent and allowed the Alphans back to their home ('The Immunity Syndrome'). Despite her sweet personality and engaging nature, Maya isn't always well viewed by those who don't know her so well. During her fit of madness, Carolyn Powell attempted to suffocate her ('The Lambda Factor'), while a security guard suggested Maya should simply be handed over to the Dorcons when they attacked the station to kidnap her ('The Dorcons').

Born in Brunei, Borneo, Sandra Benes (nicknamed "Sahn") is the principal Main Mission/Command Centre Operative. Although her duties mainly involve communications and routine handling of the computer, Sandra is also an electronics expert, as demonstrated when she guided her colleague Bill Fraser through the construction of an electric barrier in 'The Beta Cloud'.
Romantic and emotional, Sandra is often the first to react to the situations that befall the Alphans. She was engaged to be married to a young Englishman called Peter Rockwell before 'Breakaway' ('Bringers of Wonder'). In following years, she has been involved with the Eagle pilot Mike Ryan ('Black Sun'), Main Mission Controller Paul Morrow ('The Last Sunset') and pilot Alan Carter ('Full Circle').

A young botanist assigned to Hydroponics, Shermeen first came to the notice of the command staff when she developped a "teenage crush" on Tony. She was rapidly cured of this affliction when a mysterious anti-matter alien, Vindrus, persuaded her to help him bring his people into the Alphan's world, a process which would cause the destruction of everyone on Alpha. Vindrus' plan was thwarted by Koenig and Maya, and following this adventure, Shermeen started going out with her colleague Eddie Collins.

Born in Florence, Italy, Anthony Dean Verdeschi became first officer of Alpha at some point after the events depicted in the first season of Space:1999. As Koenig's second in command, Tony is also in charge of Base security, involving not only defence against alien attack, but also policing of Alpha's own population as the stresses of life in space become more apparent ('The Lambda Factor'). More importantly, Tony is entitled to take command of the base in the Commander's absence ('Catacombs of the Moon', 'Dorzak') or, indeed, question the Commander's authority if need be ('Seed of Destruction').
Off-duty, Tony is a cheerful fellow whose hobbies include beer-making ('A Matter Of Balance') and romancing Alpha's resident alien, Maya. Over the course of the second season, their relationship progressed from innocent flirting ('The Exiles') to a more serious attachment which nearly jeopardised Tony's objectivity when the Psychon Dorzak visited Alpha ('Dorzak'). In between times, there were some ups and downs, most notably when, faced with an almost certain death, Tony suddenly declared his love for Maya... only to dismiss it as "wild garbage" as soon as the danger had passed ('The Beta Cloud'). He had an older brother, Guido ('Bringers of Wonder').

A scientist assigned to Moonbase Alpha, Victor Bergman was studying the recently discovered planet Meta when the moon was wrenched out of Earth orbit. A close friend of John Koenig, he had previously worked with Koenig and the astronaut Tony Cellini on the Ultra Probe mission in 1994. This mission to investigate the extra solar planet Ultra was a failure when nearly the entire crew was wiped out by an alien monster. Bergman, Cellini and Koenig were suspended, although all three were back on Alpha by September 1999. ('Dragon's Domain')
An eloquent and intellectual man, Bergman's hobbies included philosophy and scientific research, although he may also have been a musician, judging from the violin on display in his office (Alpha Child). He was equipped with a mechanical heart which could prove an advantage (it saved his life in 'Black Sun') or an inconvenience (it shorted out when Bergman stumbled into a force field on the Gwent ship in 'The Infernal Machine'). Although his disappearance was never explained, Bergman was not present in the second season of Space:1999.

Yasko was the Command Centre operative on duty when the Moon received a communication from the 22nd-century scientist Dr. Charles Logan, who was offering to transport the Alphans back to Earth using an experimental device. The first attempt to teleport John Koenig, Alan Carter and Helena Russell was a failure when the three were transported to 14th century Scotland instead. Although they were brought back to Alpha and Dr. Logan proposed to repeat the experiment, Yasko voiced the opinion of all her colleagues when she declared she had rather "stay on Alpha than end up somewhere in space" ('Journey to Where'). Yasko's hobby is growing bonsai trees, although she was willing to exchange one for some of the trader Taybor's merchandise in 'The Taybor'.