The Pilot's remains were first discovered in a derelict spacecraft as crewmembers from the Nostromo were investigating the source of a distress signal emanating from LV-426, (now known as Acheron) an unsurveyed satellite (at that time) that orbits the gas giant, Calpamos.
The creature encountered in the derelict spaceship on Acheron (the middle of the 3 satellites that orbit Calpamos) had what may have been a trunk or breathing apparatus, extending The deceased Space Jockey in its pilot seat
vertically down a broad chest. The 'mouth' was present under the beginning of this trunk and seemed to have two mandibles (or tusks) at the sides of the mouth. This may have been simply the result of a Facehugger using its acid to access the creature within, as the outer form would appear to be a biotechnological form of 'E-suit', or Hazmat suit, the 'trunk' allowing the alien to breath in hostile atmospheres. The arms are visible to its sides and this creature appeared to have been grafted into its seat. The lower body of the creature was obscured by its seat and was not observed. The suit resembles a 15 foot tall humanoid elephant, although indications gleaned from the Prometheus Project are that the creature within is a somewhat smaller being resembling a hairless, blue-grey human, approximately 10 feet tall.
Seen from other sources, living examples of this alien species are shown to be grey or brown skinned, hairless and humanoid, with two arms and legs, and said to have staring, "dead seeming" eyes. Their pupils are in the shape of oblong plus-symbols. The species was once thought to have telepathic powers, but the Weyland-Yutani Corporation scientists have found this not to be true, from certain information deciphered off of the logging device. The distress signal picked up by the Nostromo was an acoustic beacon giving out a signal every 12 seconds.
Space Jockey, or The Pilot. It has come to light that a logging device was discovered on the derelict alien vessel, and these creatures call themselves Ossians. Little is known about these creatures but they are theorized by some to have been the creators of the Xenomorphs or "Aliens" and are supposedly masters of Bio-engineering. According to one theory, the Pilots were thought to have created the Xenomorphs either as a terraforming mechanism designed to destroy an ecosystem for later replacement or as a bio-engineered weapon designed for mass genocide. They were used to end a civil war that was tearing the Pilot civilization apart about ten million years ago, but apparently, it went horribly wrong. This theory also explains the large amount of alien eggs in the ships cargo bay under the security field. Either way, the only crew member found was the captain and was discovered with ribs protruding outward, showing that a Xenomorph chest burster had been implanted.
Information gathered by the Prometheus Project indicated that the Space Jockey race had a hand in the evolution of life on Earth, particularly humans.
Thirteen to fifteen years after the destruction of the Hadley's Hope colony on Acheron, a still-living member of this species established contact with the young woman known as Billie, while rescuing Billie and her comrades on their mission to the Xenomorph homeworld. A childhood survivor of another Xenomorph infestation on the planet Rim, Billie shared with the Pilot a longing for revenge against the entire Xenomorph species. The Pilot followed them back to Earth, where it revealed to Billie its new plan to use Earth's own xenomorph outbreak to conquer the planet.[2]
The Pilot used the power of its ship--identical to the derelict on Acheron--to begin terraforming the Earth, lowering the temperature worldwide.[3]The human government made contact with the Pilot, sending the President of the United States and other representatives to the ship to negotiate terms of surrender. Sensing betrayal, the Pilot attacked the President's party. Swallowing a capsule, the President appeared to have triggered the birth of a chestburster gestating within him, which promptly attacked the terrified Pilot. A signal was sent, and the Pilot's ship was destroyed by nuclear warheads.
Not much is known on how the space jockey ship crashed or what it was doing with the alien eggs in its hull, but there is a theory:
A space jockey was carrying Xenomorph eggs as weapons secured in a compartment covered by an electrical mist that reacted when broken, but one of the eggs "hatched" and a facehugger managed to get out and ambush the pilot by surprise. With the facehugger attached to its face the pilot was unable to maneuver the spaceship, and it crashed onto the middle satellite (LV-426 or Acheron) that orbits the ringed gas giant planet Calpamos. The pilot who later gained consciousness sent out a distress signal, but it didn't make it and the chestburster alien killed it.
"The Pilot" was so named by H.R. Giger, who originally designed the creature. It has become more popularly known as the "Space Jockey," a name that first appeared on a storyboard for the scene in Alien during which the creature first appears.[4] Director Ridley Scott has admitted that he doesn't know who had christened it as such, but the name stuck and became the unofficial moniker for the creature on set.[5]
The derelict ship contains several thousand Alien eggs. It is suggested by Ridley Scott in the director commentary to the film that the Space Jockey's ship was an "aircraft carrier or battlewagon of a civilization, and the eggs were a cargo which were essentially weapons. Like a large form of bacterialogical/biomechanoid warfare." The eggs, which are kept in the ship's hold, could presumably be dropped on an enemy planet, and the Aliens would proceed to kill the population as they spawned. "The Space Jockey was...the driver of the craft who is now, after many ages...has started to look like a perfect example of...where does biology end and technology begin, because he seems to have grafted...into what essentially was...a pilot's seat. But clearly from here, this is where the transmission would emanate from probably in an automatic transmission. So this creature obviously had experienced, maybe one of the eggs had been disturbed and a creature had got out, had attacked the rest of the crew...but let's say he was a part of the civilization he came from and now had melded into his seat." The Nostromo's computer, Mother, starts to translate the Space Jockey's transmission and it appears to Ripley to be a warning.
According to James Cameron, the Space Jockey's craft picked up Alien eggs and the pilot became infected by the dangerous cargo; the ship landed or crashed on LV-426 and the Space Jockey transmitted the signal as a warning. It is also suggested the Space Jockey encountered the Aliens on LV-426 and that it was their home planet. It is also said Space Jockeys are the Predators' enemy as well as the Aliens.
In a 2011 interview with Filmophilia.com, director Ridley Scott revealed that Space Jockey in Alien was not in and of itself an extraterrestrial creature, but rather a suit containing the actual being (which is never shown). Scott also revealed that his desire to explore the unaddressed story behind the ship on LV-426, the host of eggs aboard, and the mysterious pilot were his primary inspiration for returning to the franchise with Prometheus.[6]
In Alan Dean Foster's original Alien novelization (1979), Ash describes the Space Jockey's race as a noble people and hopes that mankind will encounter them under more pleasant circumstances. It also states that they were larger, stronger and possibly more intelligent than humans. Foster's novelization states that the Jockey was trying to warn humans away from the Aliens. Of course, Ash is also shown to be a willfully deceptive figure in the story, and this novelization differs in a number of places from the final film, as it was based on a slightly earlier draft than what was shot.
Mark Verheiden's first Aliens graphic novel (aka Aliens: Book 1, or the first Aliens comics series in 1988) depicts a living member of the Space Jockey's race as malevolent. Revealed to be alive 13-15 years after the events of Aliens, this Pilot is called a partner to the one from LV-426, and at first refrains from attacking humans due to its apparent immense hatred of their common enemy, the Xenomorphs, saving the story's protagonists on their mission to the Xenomorph homeworld. But it is then revealed the Space Jockey intends to wipe out and/or enslave humanity and conquer the Earth once its joint war with the Xenomorphs is over and that it is using a beam from space to begin terraforming the Earth into a cold and uninviting environment like LV-426. The Space Jockey creature in the series communicates telepathically with humans.
In a short follow-up comics story in Dark Horse Presents: Aliens, this second Space Jockey is shown orbitting the Earth in its spaceship--identical to the one from LV-426--which is revealed to be the source of the terraforming beam that was changing Earth. The beam by this point is said to be helping to restabilize the Earth's atmosphere. The creature is assassinated and its ship destroyed during a meeting with the President of the United States and his advisors.
In Steve Perry's Earth Hive (1992)--the novelization of Aliens: Book 1--the Space Jockey's race are referred to as collectors because they collect Xenomorph eggs.
In Michael Jan Friedman's Aliens: Original Sin (2005)--a spin-off sequel to Alien Resurrection--the race is referred to as the Mala'kak, and it is revealed that some humans have been secretly in contact and in league with the species from 200 years before Resurrection as the organization Loki.
According to the comic book The Destroying Angels (1999), the Aliens caused the species to become virtually extinct 1.6 billion years ago and when a facehugger attaches itself to a Space Jockey that was barely living, it creates an Jockey born Xenomorph as shown
The AVP game series featured the Space Jockey in two of their games. Aliens versus Predator featured a Space Jockey in the marine level "Derelict" as well as the Alien bonus level of the same name (this is the same Space Jockey from Alien). The game Aliens versus Predator 2 involves an experimental lab built on the species' artifacts and technology. At the end of the marine campaign, Harrison fights an Alien Queen in a large room with a Space Jockey in the center.
A brief mention to a Space Jockey was seen in an AVP comic where a Space Jockey ship is seen above the Xenomorph homeworld.
It has been noted that in AVP-R, you can see a Space Jockey skull in the scout ship.
It is possible that the pilot was on a mission to destroy the Xenomorph eggs. If this is true, it is more than likely that there were numerous other transports carrying Xenomorph cargo. Another possibility is that this Ossian (Space Jockey) vessel was on an exploratory mission and set down on the Xenomorph home planet, (the whereabouts as yet unknown) and a queen Xenomorph crept aboard and laid eggs without being noticed. The full horror occuring when the pilot was attacked by a "Facehugger", and as the "Chestburster" was boring its way out of the Ossian's chest, it had to in its last agonizing death throes, try to set down on the nearest available place, being one of the satellites of Calpamos, notably LV-426. (Acheron)
Trailers for Prometheus have shown a humanoid of the same size as a Space Jockey, walking towards what appears to be a Jockey ship command chair. Whether this is the real look of the Jockey without a helmet has yet to be determined.
It is possible that the Space Jockey is actually very similiar to the Human in looks but that they use some sort of bio-tech that blends with their flesh, as briefly seen in the Prometheus trailer, making them look completely different