Unraveling the enigma of the Fermi Paradox, we delve into the cosmic conundrum - the conspicuous absence of extraterrestrial life. We explore the universe's silent echoes, questioning our solitude in the cosmos, and pondering over the whereabouts of the elusive aliens.

The Fermi Paradox seeks to answer the question of where the aliens are

Given that our star and Earth are part of a young planetary system compared to the rest of the universe, the theory says that Earth should have been visited by aliens already.

  • Four arguments exploring the paradox
  • Aliens never came because of a physical difficulty that makes space travel infeasible (i.e. astronomy, biology, genetics, and/or engineering)
  • Aliens chose never to come to Earth
  • Advanced civilizations arose too recently for aliens to reach us
  • In the past, aliens have visited Earth in the past but we have not observed them

Recent Fermi paradox discussion

In 2015, a study looked at the likelihood of a world evolving with a habitable environment, using data from the Hubble Space Telescope and Kepler Space Telescope. It suggests Earth was an early bloomer.

  • Even though the study excluded intelligent life, the study suggests that our planet’s birth came very early in the universe’s history.
  • When Earth was formed about 4.6 billion years ago, only 8 percent of the potentially habitable planets that will ever form in Earth’s position existed.

Plentiful planets

The universe is incredibly vast and old. One estimate says the universe spans 92 billion light-years in diameter (while growing faster and faster). Separate measurements indicate it is about 13.82 billion years old.

  • The sheer number of planets that we have found outside of our solar system indicates that life could be plentiful.
  • Over time, with more advanced telescopes, scientists will be able to probe the chemical compositions of their atmospheres.

Life: plentiful, or rare?

The Drake Equation seeks to figure out the number of civilizations in the Milky Way that seek to communicate with each other

  • N = R*. fp. ne, fl, fi, fc, L – has the following variables
  • R* = The rate of formation of stars suitable for the development of intelligent life
  • fp = The fraction of those stars with planetary systems
  • ne = The number of planets, per solar system, with an environment suitable for life.
  • fl – the fraction of suitable planets on which life actually appears
  • fi – the size of life-bearing planets that have been confirmed by exoplanets, and the fraction that have life-causing activity on them
  • L – the length of time such civilizations release detectable signals into space

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