The structure is an indicator of the integrity of the object. We distinguish the structure of artificial man-made objects and the structure of celestial bodies of natural origin.

Artificial man-made objects are buildings, fleet and defense. Their structure is equal to their cost in the metal and minerals. To destroy an artificial object it is enough to break through its armor, which is 10% of its structure.

The structure of objects of natural origin is considered as a cubic root of [the mass*1000]. To destroy a natural object, it is necessary to destroy its entire structure. Natural objects are of the following types.
Planet is a massive static cosmic body with a diverse density. Planets revolve around their stars, suns.

Asteroids are huge hard stones, remnants of the former planets, formed after the planetary destruction. These are the densest pieces of the former planet.
Moon is a more or less homogeneous cosmic body, a fragment consisting of fleet debris connected under the influence of gravity. The density of the moon due to fused pieces of metal is very high. Moon revolves around planets or asteroids. Any objects built of moons are called satellites. They have a dense core, inherited from the moons. The amount of metal and minerals spent on all buildings increases the mass of the moon and satellite.

Bonuses to the structure of natural objects
If the diameter of the object is less than 100 km it is enveloped by Small shield dome, Large shield dome, Planetary defence and Shield crystal. They protect the structure from damage, strengthening it with its shields. When damaging an object, these external shields will first be destroyed. For objects of the xerj race, the structure is protected by armor of Hydralisks (50% of the actual value)
. The sum of the structure of defense and buildings increases the structure of the object by the formula [building structure] ^ 0.8 + [defense structure] ^ 0.8
Each mutant level Mantrid increases the structure of planets by 10%.
Each level Space station, Jump gate, Alliance bank increases the structure of the object on which they are by 1 000 000.
Each level of SuperStation increases the structure by 100%.
Each level of Dunkleosteus increases structure of the satellite by 1%.
Mutant Auxin increases the structure of Insectoid entity and Dunkleosteus by a percentage of the sum of the mutant levels.