Space is a science fiction Lego theme featuring astronauts and spaceships. It was introduced in 1978 and discontinued in 1999. Space was one of the most expansive themes in Lego history, and contained over 200 individual sets. It was outlived only by the Lego Castle theme.

Space was marketed under the Legoland banner until 1991, when the name was changed to Lego System.

The first Lego Space sets were truly a leap forward in Lego design, and by today's standards, fairly primitive. Minifigure pilots often steered their spacecraft with steering wheels; rocket engines might be simple transparent cones affixed to fence pieces; and visored helmets had not yet been introduced. In its earliest stages, Space sets consisted only of ships and basic wheeled vehicles. But as science and science fiction designs grew, the basic pattern of ground-buggies, walking robots, small and large spaceships, and bases developed.

Early Space sets had a simplistically modern yet colorful charm rivalled by no other mass-produced toy of the time. Many of the theme's more specialized pieces had not yet been developed, although when Space was first introduced, many parts were new, or were older parts made in new colors. Examples of these early simple sets include Rocket Launcher (1978), Space Shuttle, and Mobile Tracking Station (both 1979).

Perfectly suited for space, gray had finally become a major color for a Lego theme, especially as more plate-type parts were made in that color. Most often, gray sets were paired with green windows. The other predominant colors were blue with yellow windows. With the introduction of the Starfleet Voyager in 1981, classic spaceships began to appear in white, with blue canopies.

Popular spaceships and vehicles from the Classic Space era include Galaxy Explorer (1979), Starfleet Voyager (1980), Mobile Rocket Transport (1982), Galaxy Commander (1983), and Cosmic Fleet Voyager (1986).

The major bases were Space Command Center (1978), Alpha-1 Rocket Base (1979), Beta-1 Command Base (1980), Intergalactic Command Base (1984), and Polaris-I Space Lab (1987).

Complete Classic Space sets can fetch handsome sums in online auctions.

Oddly, Space was part of Legoland, an example evidenced on set box 6890 by a diagonal yellow stripe with blue lettering. The theme was later grouped under the major Lego System category, where it can often be found on reputable resource and fansites.

The first unified and truly themed theme, Blacktron took to the skies in black with yellow trim, and red and yellow transparent pieces. (The odd man out was the Meteor Monitor, which was white and black with red transparents.) Blacktron minifigures (or "minifigs" for short) wore emblematic black jumpsuits with white trim and opaque black visors. Stylish, sleek and intimidating, Blacktron was a major step up from the rather clunky design values of Classic Space. It featured a large spacecraft, the "Renegade," which set the tone for all future big ships by splitting into a number of smaller modules, including a storage bin for a small wheeled vehicle; these modules could be recombined not just with each other, but with modules from other vehicles in the set as well, specifically the "Invader" and "Battrax." This modular interchangeability has been a staple of Lego Space ever since.

Popular Blacktron I vehicles include Renegade, Invader, Battrax (all 1987) and Alienator (1988). The base was Message Intercept Base (1988).

Though Blacktron I officially ended in 1988, the Meteor Monitor (1990) was released. (Considering its slightly altered color scheme it could be viewed as being from between the "upgrade" era of Blacktron I to Blacktron II.)

Taking over from Classic Space and inheriting its white-and-blue color scheme, "Futuron" depicted an austere yet bustling settlement on the surface of a planet reminiscent of Earth's moon. It might be presumed that "Classic" race become Futurons race in the Lego Universe and that their people are one and the same. Its minifigs came in many colors (red, blue, yellow and black), but all shared the same uniform—a zipper crossing from hip to shoulder, with color on top and white below—as well as light-blue-tinted helmet visors. Instead of a big ship, the theme centered around the Monorail Transport System, which featured a battery-powered train system and some twenty linear feet of track.

Popular Futuron vehicles include Stardefender 200 (1987) and Monorail Transport System (1988). The base was Cosmic Laser Launcher (1987). (Although not officially a Futuron set, the aforementioned Polaris-I Space Lab could be considered a base in this theme as it was released at the same time and shares Futuron colours, and could be considered being from the era in which the classic race became the Futuron Race.

In 1989, Lego made a storyline decision. Blacktron, previously operating in a moral void, were now declared the "bad guys" of Lego Space; opposing them and defending Futuron from them were the Space Police, a series of brave individuals whose spacecraft were black and blue with red transparent elements. (This would be a continuing theme of space, having "bad guy" races, "good guy" races and a "civilian" race between them.) Space Police re-introduced the idea of modular systems, on a smaller but also grander scale. The Space Police I theme features three spaceships, two wheeled vehicles and a ground-based space station; all but the smallest buggy comes with a Space Police jail cell (which was often supplied with a Blacktron occupant). These jail cells were identical from set to set and could be traded around between vehicles with no hassle whatsoever. This theme marks the beginning of Lego Space's greatest period of success, and is one of the most well-loved themes of the collection; complete models of the largest ship, the Mission Commander, have been known to sell for USD $90 via online vendors.

Popular Space Police I vehicles include Spy-Trak I and Mission Commander (both 1989). The base was Space Lock-Up Isolation Base (1989).

In an effort to increase interactivity, Lego introduced magnets in the next Space theme, M:Tron, who took over the "civilian" role of the Futuron Race. Vehicles in this set, distinctive for their red hulls, gray trim and neon-yellow canopies, are devoted primarily to mining out precious ores. They often featured crane-like attachments with magnets for picking up small cargo and storage boxes. These boxes, unfortunately, were generally not interchangeable.

Popular M:Tron vehicles include Stellar Recon Voyager and Mega Core Magnetizer (both 1990).

M:Tron was the first major Space theme that did not include a base of any kind; all sets were vehicles.

M:Tron was also the last space theme to carry the Legoland banner. Lego System was the name used starting in 1991.

In 1991, Blacktron received a makeover: black with white trim, M:Tron's neon green canopies, as well as new uniforms. It also replaced the creative but haphazard interchangeability of Blacktron I with refined and mostly-uniform cockpit globes (best seen here), which could switch unimpeded between any model that featured one. In a theme containing a total of eleven vehicles, this was not seen as a marked improvement (in Blacktron I, three of five sets featured interchangeable parts). Some fans were also disappointed that, aside from a proliferation of small (50-element-or-less) vehicles, Blacktron II seemed to be mostly a rehash Blacktron I on a set-by-set basis.

Popular Blacktron II vehicles include Spectral Starguider and Aerial Intruder (both 1991). The base was Alpha Centauri Outpost (1991).

Space Police was the next theme to receive a makeover, remodeled into its more widely recognized black and grey with green canopies and red trim. The standardized jail cells were retained, though only three vehicles could accept them; the theme also lacked a permanent installation like Space Police I's Space Lock-Up Isolation Base (1989). Finally, Space Police II ships were known for being under-armed; several vehicles sported no overt weapons (such as the Galactic Chief, whose paltroon-wearing pilot appears to be armed with only a bullhorn, although many used this as a sort of large blaster, and the others having only two small weapons (including the theme's heavyweight multi-module spaceship, the Galactic Mediator).

Popular Space Police II vehicles include Rebel Hunter and Galactic Mediator (both 1992). Space Police II did not include any bases.

Though Space Police II officially ended in 1993, Starion Patrol (1993) was re-released as Space Police Car in 1999.

Taking place in a time and location that should be fairly obvious, Ice Planet can be considered M:Tron's replacement as the "civilian" race. It featured new elements such as a distinct setting (an ice planet), (skis, both on vehicles and personnel), and bright neon cockpits (orange). As befitting an icebound theme, most of its vehicles were ground-based; many of its smaller vehicles also showcased satellite dishes.

Popular Ice Planet vehicles include Ice-Sat V and their largest and only starship the Deep Freeze Defender (both 1993). The base was Ice Station Odyssey (1993). All three sets included Apollo type rockets.

Though Ice Planet officially ended in 1994, Snow Scooter (1994) was re-released as Space Diver in 1999.

Taking over the "good guy" race from the Space Police II was the Unitron, a more military themed group. Unitron also features elements from the classic Futuron line, as it revolved around a large monorail system powered by a 9V battery; it retained Lego interchangeability in the form of small, sleek cockpits which could dock on the front or top of its vehicles. Unfortunately, aside from a ground installation, a large buggy, an advanced looking spaceship, and aforementioned monorail, the theme was underdeveloped, a fact that is still lamented today.

The two Unitron vehicles were Crater Cruiser and their largest starcraft Star Hawk II (both 1995) (which oddly was only half the size for most of the other races' largest starships). The base was Space Station Zenon (1995). The monorail system was Monorail Transport Base (1994).

Red and black, with blue cockpits, Spyrius homeworld appeared to be a craggy, desolate moon. The Spyrius took over the "bad guy" race theme as a group of spies out to steal technology and valuable data to either horde or seal to the highest bidder (presumably either the Blacktron or any of the following "evil" races that came after). This nine-set theme was the first to feature robot minifigs.

Popular Spyrius vehicles include Saucer Scout and their largest starcraft the Saucer Centurion (both 1994) (which, like the Unitron's Star Hawk II, as smaller then the largest starships of other races). The base was Lunar Launch Site (1994). The theme also included two robot vehicles, Recon Robot and Robo-Guardian (both 1994).

Though Spyrius officially ended in 1996, Surveillance Scooter (1995) was re-released as Space Jet in 1999.

Returning to the clean white lines and blue cockpits of Futuron (as well as their civilian role), Exploriens sets are known for their use of large, open (sometimes rickety) structures and special image elements (e.g., as foil-holograph stickers for viewscreens). The Exploriens were searching, evidently, for fossils, certain flat plates contained triple images: one in white, for the naked eye; one in blue, for viewing under transparent red scanners; and one in red, for viewing under transparent blue scanners. It was the second space theme to include a robot minifigure.

Popular Exploriens vehicles include Scorpion Detector and their largest starcraft the Explorien Starship (both 1996). The base was Android Base (1996). A mini-base was also included, Nebula Outpost (1996).

Taking the "good guy" role was another four-set theme, Roboforce featured various large robots (arguably mecha) in varying color schemes. Orange Class features a police-like patrol function in humanoid robos, equipped with buzz saws for extracting criminals or rescuing civilians. The "head" of each robo was also a small space ship that could be used as an escape pod or secondary vehicle. Green Class featured a more military theme with animal shaped robos. The Robo Raptor was the only set not to feature a space craft, while the Robo Master's small starcraft strongly resembled the Unitron Star Hawk II as a tribute to the fan favorite set. Roboforce "Robos" were powered by "secret" "robo disk" which were oddly enough rectangle-shaped power sources. By this time, Roboforce was well and truly exhausted, and the remaining sets were a slow march to the theme's obscurity.

Orange Class: Small Variant Robo Raider (1997) Orange Class: Large Variant Robo Stalker (1997) Green Class: Small Variant Robo Raptor (1997) Green Class: Large Variant Robo Master (1997)

UFO was the first theme to introduce what has since become a staple of Lego sets in general: large pieces meant to provide effects (such as curvature) that would be difficult to achieve with traditional Lego pieces. Consequently, these can be difficult to use on other creations. The "UFOians" or simply the "Aliens" took the role of the "bad guys" abducting and terrorizing the civilian races. All of UFO's minifigures were cybernetic in nature, and the race featured two wholely robot figures, and, as befitting its name, many of its spaceships used saucers or half-saucers as elements. It has the smallest proportion of wheeled ground vehicles to ships (two to nine) of any Lego Space theme before or since.

Popular UFO ships inculde Warp Wing Fighterand their largest starship the Interstellar Starfighter (both 1997). The UFO had no primary base however when the smaller saucer detached from the main hull of the Alien Avenger (1997) the bottom half was converted into a command center.

Insectoids were especially interested in "energy orbs" which included magnetic stickers so that magnets attached to cranes could lift them. Predictably the Insectoids utilized a number of pieces designed to look like insect components, particularly legs and wings. Its minifigures were primarily cybernetic, and it is the only Lego theme to have a female minifigure as its sole leader, the Queen.

Popular Insectoids vehicles include Bi-Wing Blaster and Celestial Stinger (both 1998). The base was the mobile and bizarre Arachnoid Star Base (1998).

Life On Mars was the last LEGO Space theme to date, and is the only one with both Humans and Aliens. The Martians base was 7317 Aero Tube Hangar, and the Humans base was 7315 Solar Explorer.