Geographic location of the Kerbal Space Center.

Kerbin is the home planet of the kerbals. It is the third largest planet in the Kerbol system as well as the third planet away from Kerbol. It is one of the two waterworlds in the Kerbol system as well Laythe being the second. It has two natural satellites orbiting it; the Mun and Minmus.

Reaching a stable orbit around Kerbin is one of the first milestones the player achieves in the game. Achieving such an orbit with a fuel-optimal ascent[1] requires a delta-V of roughly 4500 m/s,[2] the second largest of all celestial bodies with a solid surface after Eve. For many interplanetary missions, this represents over half of the flight's total delta-V requirement.


Kerbin has a roughly equal distribution of surface liquid water and solid land, with polar ice caps and scattered deserts. There are mountains exceeding 4 km in height, with the tallest peak being just under 4044 m in altitude.

Kerbin shows signs of having been impacted by an asteroid or comet. That is visible in the large crater in the western hemisphere. The crater's central peak is visible from orbit and was caused by the compression followed by the rebound of material in the center of the crater.

Kerbal Space CenterEdit

The Kerbal Space Center is comprised of an aircraft hangar, a launch pad, the Tracking Station, a vehicle assembly building, and the space plane takeoff/landing strip. The Space Center is located on the eastern edge of a large peninsula shaped vaguely like Africa. It is located almost on the equator, making it much easier to achieve an orbit parallel to Kerbin's orbital plane, as well as the Mun's.

Atmosphere Edit

The atmosphere is similar to Earth's one (1 atm or roughly 101 kPa), so it is suitable for an aero-brake. It slowly fades away in outer space at about 100 km (but Kerbals set a limit to 70 km) and it is divided in 4 layers. The first two layers are mostly made of normal air (nitrogen, oxigen, carbon dioxide, ozone), the third of molecular oxygen (O) and the fourth of helium and hydrogen

The Troposphere Edit

This layer stretches between the sea level and 12,000 m. In here all Kerbin's life is located and the air is thick enough to create heat when breaking the sound barrier. This is the ideal layer where to deploy your main chute.

The Stratosphere Edit

Between 12,000 m and 18,000 m there is the Stratosphere. Here, you can easily break the sound barrier without any real damage but an aero-brake still persists. An ozone layer protects Kerbin from deadly UV rays. This is the ideal layer to deploy your drogue chute.

The Thermosphere Edit

This layer is called so because air particles are heated by Kerbol, but reentry heat is caused by the friction of the spaceship with the air. It is located between 20,000 m and 50 km. A normal reentry (2300 m/s) begins at 48~50 km.

The Exosphere Edit

Between 50 km and 100 km is located the exosphere, but at 70 km space begins. Here the really thin air fades into interplanetary space.

The Kerbin System Edit

The Mun Edit

The mun, also known as Mün, is the first moon orbiting Kerbin. It can be thought of as an analogue to Earth's own moon. It is gray in appearance with craters and mountains exceeding 5000 m in height. The gravitational pull on the surface is 1.63 m/s². It is possible to land on the Mun or use it for gravity assist (gravitational slingshots) to outer bodies. This body has no atmosphere so no parachute will work.

Minmus Edit

Minmus is the second and smallest moon of Kerbin. From the surface of Kerbin or the Mun, it is a cyan speck one or two pixels . This is a result of viewing its rotation from afar. Up close, it is off white in appearance with what seem to be icy buttes, large hills, and frozen lakes. The highest areas are over 5.7 km in altitude. It requires more delta-v to reach Minmus orbit than Mun orbit; however it requires much less to land on the surface.


It is often necessary to use moderately sized, multi-stage rockets to acquire a significant orbital altitude with large payloads or cockpits containing one or more Kerbals. These do not need to be particularly large; the default Kerbal X rocket is perfectly capable of reaching the Mun, but not necessarily capable of landing or returning in a safe manner. It is, however, possible to achieve orbit and safe reentry with a rocket of this size.

Launch of a rocket is best done following Kerbin's rotation; that is, east. This is often done by tilting the rocket to the right, if the player accepts the default orientation for the cockpit/cabin of the spacecraft. Launching with an eastward tilt lowers the orbital escape velocity of your craft by about 150 m/s of delta-V.

Reentry is best done using retrograde thrusters while outside the atmosphere, and parachutes once you have reached lower altitudes. Drogue chutes may be necessary if the craft's reentry velocity is too high.

Easter eggs (Spoilers!) Edit

The are many hidden objects on Kerbin the black monoliths being the most common, one is close by the space center and can easily be discovered. Some buildings may be found and will give you an milestone reward when you find them.

  • The ancient spaceplane hangar and landing strip; This is placed on an island right east for the space center. Landing here might be tricky since the runway is bumpy landing here will give you some funds as a milestone reward.
  • There is an ancient space center somewhere on Kerbin finding this and taking samples from it gives you the same results as in the same space center! Finding it gives you some funds.


Orbital Characteristics
Semi-Major Axis 13 599 840 256 m (1)
Apoapsis 13 599 840 256 m (1)
Periapsis 13 599 840 256 m (1)
Orbital Eccentricity 0
Orbital Inclination 0 °
Argument of periapsis 0 °
Longitude of the ascending node 0 °
Mean Anomaly 3.14 rad (at 0s UT)
Siderial orbital period 9 203 545 s
426 d 0 h 32 m 24.6 s (Kerbin time)

106 d 12 h 32 m 24.6 s (Earth time)

Synodic orbital period Not defined
Orbital Velocity 9284.5 m/s
Physical Characteristics
Equatorial Radius 600 000 m
Surface Area 4.5238934×1012 m2
Mass 5.2915793×1022 kg
Gravitational Parameter 3.5316000×1012 m3/s2
Density 58 484.791 kg/m3
Surface Gravity 9.81 m/s2
Escape Velocity 3 431.03 m/s
Sidereal Rotation Period 21 600.000 s
6 h 0 m 0 s
Sidereal Rotational Velocity 174.53 m/s
Synchronous Orbit 2 868.75 km
Sphere of Influence 84 159 286 m
Highest elevation 4044 m
Atmospheric Characteristics
Atmosphere Present Yes
Atmospheric Pressure 101 kPa
1 atm
Scale Height 5000 m
Atmospheric Height 69 077.553 m
1.0×10-6 atm
Temperaturemin -40.19 °C 232.96 K
Temperaturemax 20 °C 293.15 K
Oxygen Present Yes
Community content is available under CC-BY-SA unless otherwise noted.