Any wonder we are not alone and being visited for a very long time. So if there are so many earth like planets and if we were to guess that 0.1% had
life. How many Intelligent species would there be? More than 57 thats for sure!
Gets more interesting by the month.]
I did a rough calculation:
200 billion (number of stars in our Milky Way galaxy) *times* 11% (the percentage of stars like our Sun) = 22,000,000,000 Sunlike stars
22,000,000,000 Sunlike stars *times* 22% (the percentage of Sunlike stars that have habitable Earth sized planets based on today's announcement) =
440,000,000 Earthlike habitable planets in our Milky Way galaxy
440,000,000 Earthlike habitable worlds /divided by volume of the Milky Way Galaxy.....
Uh oh... time to do some more math...
The volume of the Milky Way can be approximated by a disk with a thickness of 1000 light years and a radius of 50,000 light years.
For simplicity I will use the formula for calculating the volume of a sphere: The formula is V = 4/3 π r cubed.
r = 50,000 light years
The cube of the radius - 1,350,000 light years
Multiply 1,350,000 light years by 4 over 3 (4/3 or 1.33333333333 in decimals) = 1,800,000 light years
Multiply 1,800,000 light years by π (pi) = 5,654,867
So the volume of the Milky Way - 5,654,867 light years
So to conclude 440,000,000 Earths divided by 5,654,867 (the volume of our Milky Way galaxy in light years) = 78.6 Earthlike planets cubed per a 100
light year volume on average = 647 Earths within a 100 light year sphere
So about 647 stars within 100 light years should have a planet like the Earth.
If we assume only 1% of those Earthlike planets produce technological intelligences then that = around 6.5 intelligent species within 100 light years
of the Earth and a total of 44 million intelligent species in the Galaxy.
(I put money on us being the 0.5 in that figure by the way
edit on 4-11-2013 by JadeStar because: (no reason given)
edit on 4-11-2013 by JadeStar because: (no