UFOs/Aliens/I have a question.
I am a 15 year old high school freshman, a female and living in Mississippi. I am writing an English paper on the topic, "Could aliens exist?" I have asked a few people and their answers were so vague that I thought "Hey, why not consult the internet?" I saw your bio and you looked like a good expert and that's how I got here. Thank you for your time.
Well, since this question is being asked in relation to a homework assignment here in the US, I'll refrain from using biblical references (as this may only cause problems in that respect).
In a scientific sense, the mathematical equation which insists upon the possibility of intelligent life elsewhere in the universe leans for more toward yes than no. And this equation is in no way related to simply beliefs or conspiracy theories. These are simply facts. It's called the Drake Equation.
The equation can really be looked at as a number of questions:
N* represents the number of stars in the Milky Way Galaxy
Question: How many stars are in the Milky Way Galaxy?
Answer: Current estimates are 100 billion.
fp is the fraction of stars that have planets around them
Question: What percentage of stars have planetary systems?
Answer: Current estimates range from 20% to 50%.
ne is the number of planets per star that are capable of sustaining life
Question: For each star that does have a planetary system, how many planets are capable of sustaining life?
Answer: Current estimates range from 1 to 5.
fl is the fraction of planets in ne where life evolves
Question: On what percentage of the planets that are capable of sustaining life does life actually evolve?
Answer: Current estimates range from 100% (where life can evolve it will) down to close to 0%.
fi is the fraction of fl where intelligent life evolves
Question: On the planets where life does evolve, what percentage evolves intelligent life?
Answer: Estimates range from 100% (intelligence is such a survival advantage that it will certainly evolve) down to near 0%.
fc is the fraction of fi that communicate
Question: What percentage of intelligent races have the means and the desire to communicate?
Answer: 10% to 20%
fL is fraction of the planet's life during which the communicating civilizations live
Question: For each civilization that does communicate, for what fraction of the planet's life does the civilization survive?
Answer: This is the toughest of the questions. If we take Earth as an example, the expected lifetime of our Sun and the Earth is roughly 10 billion years. So far we've been communicating with radio waves for less than 100 years. How long will our civilization survive? Will we destroy ourselves in a few years like some predict or will we overcome our problems and survive for millennia? If we were destroyed tomorrow the answer to this question would be 1/100,000,000th. If we survive for 10,000 years the answer will be 1/1,000,000th.
When all of these variables are multiplied together when come up with:
N, the number of communicating civilizations in the galaxy.
However, based on these predetermined answers to each of the questions, the average amount of extraterrestrial civilizations that would exist is roughly 1000.
But look at it this way...
Even if we lowered our expectations and placed the answer to these questions as low as we possibly could (even lower than a fraction of mere common sense), then the answer would still be no less than 3 no matter how you looked at it.
So the possibility that intelligent extraterrestrial life DOES exist “somewhere” other than here in our own solar system would be a resounding indisputable YES. The only time someone would answer otherwise is if that person is unaware of the actual mathematics or are simply allowing their vague beliefs get in the way.
The only REAL question is... Will we ever meet them? And anly time can answer that one.