Kerbal Space Program
|Kerbal Space Program|
|Designer(s)||Felipe Falanghe, Paul Boyle|
|Programmer(s)||Jamie Leighton, David Tregoning|
|Release||Microsoft Windows, macOS, Linux|
PlayStation 4, Xbox One
|Genre(s)||Space flight simulation|
Kerbal Space Program, commonly abbreviated as KSP, is a space flight simulation video game developed and published by Squad for Microsoft Windows, macOS, Linux, PlayStation 4, and Xbox One. In the game, players direct a nascent space program, staffed and crewed by green humanoid aliens known as "Kerbals". The game features a realistic orbital physics engine, allowing for various real-life orbital maneuvers such as Hohmann transfer orbits and bi-elliptic transfer orbits.
The first public version was released digitally on Squad's Kerbal Space Program storefront on 24 June 2011, and joined Steam's early access program on 20 March 2013. The game was released out of beta on 27 April 2015. Kerbal Space Program has support for user-created mods that add new features, and popular ones, such as those for resource mining and context-based missions, have received support and inclusion in the game by Squad. People and agencies in the space industry have taken an interest in the game, including NASA.
In May 2017, Squad announced that the game was purchased by video game company Take-Two Interactive, who will help support Squad in keeping the console versions up-to-date alongside the personal computer versions. An Enhanced Edition was released on the Xbox One and PlayStation 4 in January 2018 by Private Division, a publishing subsidiary of Take-Two Interactive. Two expansions for the game have been released as downloadable content: Making History in March 2018 and Breaking Ground in May 2019.
The player administers a space program operated by Kerbals, a species of small green humanoids, who have constructed a fully furnished and functional spaceport called the Kerbal Space Center (KSC) on their home planet, Kerbin. Despite being shown as cartoonish beings sometimes lacking common sense, Kerbals have shown themselves capable of constructing complex spacecraft parts and performing experiments to realize their scientific goals.
Players can create rockets, aircraft, spaceplanes, rovers, and other craft from a provided set of components. Once built, the craft can be launched by players from the KSC launch pad or runway, or other launch pads and runways around Kerbin, in an attempt to complete player-set or game-directed missions while avoiding partial or catastrophic failure (such as lack of fuel or structural failure). Players control their spacecraft in three dimensions with little assistance other than a stability system called "SAS" to keep their rocket oriented. Provided it maintains sufficient thrust and fuel, a spacecraft can enter orbit or even travel to other celestial bodies. To visualize vehicle trajectory, the player must switch into map mode; this displays the orbit or trajectory of the player vehicle, as well as the position and trajectory of other spacecraft and planetary bodies. These planets and other vehicles can be targeted to view information needed for rendezvous and docking, such as ascending and descending nodes, target direction, and relative velocity to the target. While in map mode, players can also access maneuver nodes to plan out trajectory changes in advance.
Missions (either player-set or assigned "contracts") involve goals such as reaching a certain altitude, escaping the atmosphere, reaching a stable orbit, landing on a certain planetary body, capturing asteroids, and creating space stations and surface bases. Players may also set challenges for each other on the game's forums, such as visiting all five moons of Jool (the in-game analog for Jupiter), or use mods to test each other's spacecraft in air combat tournaments.
Players can control in-game astronauts, known as Kerbals, who can perform extravehicular activities (EVA). While on EVA, Kerbals may use their EVA suit propellant system to maneuver in space and around craft and space stations, similar to the use of NASA's Manned Maneuvering Unit. Actions that can be performed while on EVA include repairing landing legs, wheels, and parachutes. Kerbals can also collect material from science experiments, allowing them to store data inside the ship's capsule. During an EVA on any solid planet or moon, a Kerbal can place a flag or take a surface sample.
Historical spacecraft can be recreated and their accomplishments mimicked, such as the Apollo program, the Mars Science Laboratory rover, or the International Space Station. Players may install mods which implement destinations, weapons, rocket parts, and goals, such as attempting challenges in a real-scale solar system. Mods can also add informational displays showing craft and orbital statistics such as delta-v and orbital inclination. Some mods have been added into the game officially, due to popularity. For example, resource mining, in order to obtain Ore for refining into resources such as fuel, has been officially implemented from a popular mod.
As of version 1.7, the major celestial bodies in the game in order of their proximity to the parent star, the Sun, are Moho, Eve, Kerbin, Duna, Dres, Jool, and Eeloo (respectively analogs of Mercury, Venus, Earth, Mars, Ceres, Jupiter, and Pluto). Community modifications are able to expand this planetary system to include analogs of the missing outer planets, as well as fictional bodies and faraway exoplanet systems.
The player starts a new game by choosing one of three game modes: sandbox, science, and career mode. In sandbox mode, players may attempt to construct a suitable vehicle for any desired project without penalties for failure and entirely user-assigned missions. Many players have constructed unrealistic spacecraft in this mode, such as impractically large, complicated, or expensive rockets. This mode is also frequently used to create replicas of real-life aircraft, rockets, trains, boats, cars, and other types of vehicles.
In science mode, the initial selection of parts is limited. More complex parts can be unlocked in the Research and Development building by advancing "science" with various experiments on Kerbin and elsewhere throughout the solar system. This mode was designed to ease new players into the game and prevent them from getting overwhelmed.
Career mode extends science mode by adding funds, reputation, and contracts. To build and launch new rockets, the players must complete contracts, earning funds to pay for the necessary parts. Reputation affects how many contracts are given to the player; less reputation leads to fewer, lower-quality contracts. Declining a contract will reduce the likelihood that a contract of the same type will appear later. Simultaneously, players must upgrade buildings in the space center to unlock new features such as improved tracking, higher spacecraft mass limit, larger part count limit, and increased available contracts.
There are three currencies in Kerbal Space Program: Science, Credits or Funds, and Reputation. Although credits are the in-game analogs of money, Science and Reputation are referred to as currency as well. In Sandbox mode, no currencies are available, as there is no need for them. In Science mode, only science is available. All three currencies are available in Career mode.
Science is gained by performing experiments or crew reports. The experiments can only be turned into Science through either transmissions via antennae or recovery of a craft on Kerbin. Recovery of an experiment is worth more science than transmitting it. Each time an experiment is turned into science, it is worth less science the next time it is recovered, until it is worth no Science at all.
Funds, or credits, can be obtained in two ways: One; completing contracts by various agencies, and Two; by exploring new celestial bodies (in which a record-keeping society rewards you with a few thousand funds). The Kerbin World Record-Keeping Society does have contracts; however, the rewards for exploring celestial bodies are not contracts. Contracts are accepted through the Mission Control building in KSC, and are completed during flight.
Reputation is gained through successful missions, and lost through failed ones. It is essentially how safe Kerbals believe it is to fly on your spacecraft. More reputation results in better contracts.
While the game is not a perfect simulation of reality, it has been praised for its accurate orbital mechanics; all objects in the game except the celestial bodies are simulated using Newtonian dynamics. For instance, rocket thrust is applied to a vehicle's frame based on the placement of force-generating elements, and joints between parts have limited strength, allowing vehicles to be torn apart by excessive or misdirected forces.
The game simulates trajectories and orbits using patched conic approximation instead of a full n-body simulation; thus, it does not support Lagrange points, perturbations, Lissajous orbits, halo orbits or tidal forces. According to the developers, implementing full n-body physics would require the entire physics engine to be rewritten.
The in-game astronauts, Kerbals, are physically simulated. Hitting an object with their feet will cause them to tumble.
Some celestial bodies have atmospheres of varying heights and densities, affecting the impact of drag on wings and parachutes. The simulations are accurate enough that real-world techniques such as aerobraking are viable methods of navigating the solar system. Aerobraking, however, has become a much more difficult method of velocity reduction since the full 1.0 release due to improved aerodynamics and optional heating during atmospheric entry. In-game atmospheres thin out into space but have finite heights, unlike real atmospheres.
Kerbal Space Program alters the scale of its solar system for gameplay purposes. For example, Kerbin (the game's analog of Earth) has a radius of only 600 kilometres (370 mi), approximately 1⁄10 that of Earth's. To compensate for the gravitational consequences of this size difference, Kerbin's density is over 10 times that of Earth's. The planets themselves are also significantly closer together than the planets in the real-life solar system. However, some mods port the real-world solar system into the game with accurate scaling, environments, and additional parts to make up for the extra power requirements.
History and development
Director Felipe Falanghe was hired by Squad in April 2010. At the time, the company did not develop software. According to Falanghe, the name "Kerbal" came from the names he gave small tin figurines he installed in modified fireworks as a teenager. In October 2010, development on Kerbal Space Program was authorized by co-founder Adrian Goya but deferred until Falanghe had completed his projects. Kerbal Space Program was first compiled on 17 January 2011. The game's first public release, version 0.7.3, was on 24 June 2011. The game entered beta on 14 December 2014, with version 0.90, and was released out of beta on 27 April 2015.
Version 0.7.3 was the first public release of Kerbal Space Program, and was released on 24 June 2011. It was downloaded over 5,000 times. The version lacked many features present in later versions, such as a stability assist mode. Kerbin did not rotate, and the sun was simply a directional light source. There were no fuel flow mechanics, no control surfaces, and no other celestial bodies. Later versions added additional planets and moons, as well as the ability to load and save collections of parts, known as "subassemblies". Tutorials were also added at this stage.
Version 0.24, titled First Contract and released on 17 July 2014, added the contracts and reputation system to the game's career mode; however, players were still able to play career mode without these features in the new science mode. Contracts reward the player with currency and reputation. Funds can be used to purchase rocket parts, and reputation results in better and more lucrative contracts.
The final alpha release, 0.25, included a new economic system, and a major rework of aircraft components.
Version 0.90, nicknamed Beta Than Ever, was released on 15 December 2014. This was the only beta update for Kerbal Space Program. Featuring extensively rewritten code for the editor, it introduced the ability to sort parts by several characteristics and to assign parts to custom categories. Players could now offset parts, including into space. Career mode featured building upgrades; only the creation of small rockets with low mass and a part count is initially supported, but the player can upgrade each of the facilities to increase size limitations or unlock other capabilities.
Version 1.0 was the first full release of Kerbal Space Program. It was nicknamed We Have Liftoff! and released on 27 April 2015. Version 1.0 completely overhauled the flight and drag model for a more realistic simulation, now ignoring drag on rocket parts which were occluded from the air flow. It also allowed for body lift, so that parts that were not specifically designed as wings (such as structural panels) could still generate lift. 1.0 added shock heating and heat shields, making atmospheric entry much more dangerous, as well as air brakes and procedurally generated fairings. All parts received internal modeling. Resource mining was added to refine into fuel or monopropellant. 1.0 also brought several improvements to Kerbals, who could now have various specializations. For example, "Engineer" Kerbals can repair wheels and landing legs. Female Kerbals were also added to the game. Version 1.1, nicknamed Turbo Charged, was released on 19 April 2016, almost one year after the last major update. The game engine was upgraded from Unity 4 to Unity 5, resulting in a massive increase in performance, as well as a stable 64-bit client, removing memory constraints caused by too many mods being installed. Much of the game was rewritten to accomplish this.
Squad released Version 1.2, nicknamed Loud And Clear, to upgrade the game from Unity 5 to 5.4 and introduce performance and minor gameplay improvements. The patch entered experimental testing on 6 September 2016 and was officially released on 11 October 2016. Its main new features include communication satellites, relay systems, and KerbNet.
Version 1.3, nicknamed Away with Words, was released on 25 May 2017. Unlike its predecessors, this version lacks significant gameplay and performance changes, instead focusing on the localization of the game to Spanish, Russian, Japanese, and Simplified Chinese.
Version 1.4, called Away With Words Mk-II, was released on 6 March 2018. it expanded the range of supported languages by adding translations to French, Italian, German, and Brazilian Portuguese. The Making History DLC (see below) was also released alongside this update and added a new mission creation system along with a new set of parts.
Version 1.5, nicknamed Dressed for Success, was released on 15 October 2018 along with an update for the Making History DLC. It added new internal and external suits for Kerbals along with capability for putting Kerbals in command seats inside the vehicle editor, and visual changes for parts.
Version 1.6, nicknamed To Vee or not To Vee, was released on 19 December 2018 along with an update for Making History DLC. It added a delta-v readout for every stage in the editor and flight, along with capability for removing helmets on EVA, and visual changes for parts.
Version 1.7, nicknamed Room to Maneuver, was released on 10 April 2019 along with an update for Making History DLC. It added a precise maneuver node editor, more in-depth orbital information to the in flight UI, a ground level mode for the in flight altimeter, and visual changes for parts.
Version 1.8, nicknamed Moar Boosters!!!, was released on 16 October 2019 along with an update for Making History DLC and for Breaking Ground DLC. It upgraded the engine to Unity 2019.2, deprecating the DirectX 9 API in favor of DirectX 11, while implementing new terrain shaders and textures for several bodies.
Other updates, Take-Two Interactive ownership
On 27 January 2014, it was revealed that Squad was working on an education-themed version of the game entitled KerbalEdu in collaboration with TeacherGaming LLC, creators of MinecraftEdu. It has since been released and includes an improved user interface for easier data gathering and summary, pre-made lessons that focus on certain constructions, options to use the metric system, and a "robust pedagogy" that includes information outside of the game that ties into its content.
The majority of the game's music was provided by royalty-free composer Kevin MacLeod, with the rest of the soundtrack having been written by Squad's in-house composer Victor Machado. The game's main theme was composed by lead designer Felipe Falanghe and arranged by Machado.
On 5 June 2015, it was announced that Kerbal Space Program was being ported to the PlayStation 4 by Flying Tiger Entertainment. In August 2015, it was announced that Xbox One and Wii U ports were also in development by Flying Tiger Entertainment.
The game has since been released on the PlayStation 4 and Xbox One, but Squad has been quiet regarding the announced Wii U port. In January 2017, one of Squad's developers had finally broke the silence on the official forums, and admitted that despite initial enthusiasm to release the game on the Wii U, they claimed that various "external factors" has forced them to reevaluate supporting the console. They added that additional details will be announced at a later date.
On 17 March 2017, Squad announced a full expansion for the game; called Making History, it would be paid and contain new features. These new features included Mission Builder, which would allow players to create and edit their missions that players could complete by launching and operating various rockets and ships in the game, and History Pack, which would provide designed missions simulating important historical space endeavors that have been completed in real life. Squad announced on 7 February 2018 that the expansion would be released on 13 March 2018. The expansion contains many parts inspired by those used in various rockets such as the Soyuz spacecraft and the Saturn V.
Squad announced in May 2017 that Kerbal Space Program has been acquired by publisher Take-Two Interactive; this acquisition does not affect Squad's development or plans for the game and early backers will still get free DLC, and with Take-Two's help as a publisher, better support Kerbal Space Program on consoles to keep those versions to-date alongside the personal computer ones. Kerbal Space Program will be one of the first titles published under Take-Two Interactives's 2017-launched Private Division, a publishing label aimed to support mid-sized development studios.
In late May 2019, Squad released the Breaking Ground expansion, which includes servos, pistons, redesigned space suits, and experiments which can be deployed to earn science over time.
Kerbal Space Program 2 was announced at Gamescom 2019 on August 19, 2019. The game is being developed by Star Theory and Private Division, with projected release date some time in mid 2020. The sequel will build on the current sandbox features of Kerbal Space Program, while at the same time introducing new propulsion methods (e.g. the Orion drive), habitation modules for building on-surface and orbital planetary colonies, a highly requested multiplayer mode, as well as interstellar travel. Development was shifted to Star Theory in part so that Squad could focus on developing further updates for the original game.
This section needs expansion. You can help by adding to it. (May 2017)
The public alpha and beta releases were well received. Many publications have spoken positively of the game, praising its replay value and creative aspects, including Kotaku, Rock, Paper, Shotgun, IGN, GameSpy, Eurogamer, Polygon, and Destructoid.
In May 2015, PC Gamer awarded Kerbal Space Program 1.0 a score of 96 out of 100, their highest review score of 2015. They praised the "perfect blend of science and slapstick", as well as the sense of accomplishment felt upon reaching other planets and completing goals. IGN has praised Kerbal Space Program's ability to create fun out of failure, saying that "By the time I finally built a rocket that achieved successful orbit, I had failed so many times that in almost any other game I would have given up completely."
In their review, Edge thought that "The magic of Kerbal Space Program is not just that it manages to be both a game and a simulation, a high-level educational tool and something that is fun to simply sit and tinker with. It's that, in combination, these qualities allow for a connection with real history and real human achievement... Its ultimate promise to the player is not that you'll crack a puzzle that has been set by a designer, but that you'll crack a puzzle set by reality."
Squad has also released physical merchandise such as clothing and plush toys. In March 2015, Squad and 3D printing service Eucl3D announced a partnership that would allow players to order 3D printed models of their craft.
The game has crossed over into the scientific community with scientists and members of the space industry displaying an interest in the game, including NASA, ESA, ULA's Tory Bruno, and SpaceX's Elon Musk,. Squad has added a NASA-based Asteroid Redirect Mission pack to the game, allowing players to track and capture asteroids for mining and study. Squad has also developed an official mod for the game centered around observing and tracking threatening asteroids, named "Asteroid Day". The mod was developed in partnership with the B612 Foundation. Some parts from this mod outside of core functionality were added as part of the release of the 1.1 update, with full integration of the mod to stock game being the version 1.3.
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