second-level civilization,
That' s a Dyson sphere,
Civilizations that reach this level should be able to travel easily between stars,
for the use of civilization itself,
Even entire civilizations can live in a Dyson sphere,
It' s a huge building that encloses almost the entire star,
The second level is the stellar civilization,
If a cosmic civilization can successfully control the Dyson sphere,
However, the technological level needs to be sufficiently developed,
For example, you can arbitrarily travel between the Milky Way galaxy with a diameter of about 100,000 light-years,
A Dyson sphere will completely enclose
including the energy of other planets, and even stars,
even developed a way to travel faster than the speed of light,
Dyson spheres are like huge structures made up of countless solar sails,
is able to exploit the energy in its star system,
Then it can be said that it is already a stellar civilization,
Harvest almost all the energy of stars with high-tech level,
can utilize the full energy of the star system in which it is controlled,
And for the second-level stellar civilization,
Dyson spheres are theoretically possible,
There is a good measure of,
na looked at the transparent wooden rimless smart glasses,
For example, the warp engine technology,
Say slowly:
One possible way to harness stellar energy is the Dyson sphere,
In theory,
This also means,
The Dyson sphere is simply,