The number of technological civilizations in our galaxy is limited by

Question

Quizplus · Accepted Answer

All of the factors listed - the number of stars, the fraction of stars with planets, the number of habitable planets, and the fraction of those planets where advanced life can evolve - play a role in determining the number of technological civilizations in our galaxy. A small change in any one of these factors could greatly impact the estimated number of civilizations. All of the factors listed contribute to limiting the number of technological civilizations in our galaxy. A smaller number of stars or a smaller fraction of stars with planets would mean there are fewer potential places for life to emerge. Even if a star has planets, not all of those planets will be in the habitable zone where temperatures are suitable for life as we know it. And even if a planet is in the habitable zone, there are still many other factors that make it suitable for supporting life, such as the planet's composition, atmosphere, and magnetic field. Finally, even if all of these factors are met, there is still the question of whether or not life will actually emerge and evolve into intelligent, technological beings.

The Number of Technological Civilizations in Our Galaxy Is Limited