Could there be 100,000,000 other civilizations scattered out across the universe? Or only 10? Or what are the chances that WE are alone? Features a step-by-step mathematical assessment (using Drake's equation) to calculate the possibilities of life, or even civilizations, elsewhere in the universe.
2. Does life exist
elsewhere
in the universe?
Photo courtesy of NASA
3. Images courtesy of R. Femmer
And might there be other
advanced civilizations out there?
4. Images courtesy of R. Femmer
What are the chances of
technologically-advanced
civilizations elsewhere in the
universe?
And how many such
civilizations, if any,
might there be?
6. But we can conduct a preliminary
analysis using “The Drake Equation”
Photo courtesy of NASA
7. The math that we will use is
known as The Drake Equation
*
N = ( R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
8. N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
9. The equation was originally developed by
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Dr. Frank Drake
When he was professor of physics
and astrophysics at the
University of California, Santa Cruz
11. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
We would like to
estimate “N” – the
potential numbers of
technologically
advanced
civilizations
elsewhere in the
universe
Photo courtesy of NASA
12. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
We would like to
estimate “N” – the
potential numbers of
technologically
advanced
civilizations
elsewhere in the
universe
Photo courtesy of NASA
The number will vary, of course, with
different starting assumptions
13. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
We would like to
estimate “N” – the
potential numbers of
technologically
advanced
civilizations
elsewhere in the
universe
Photo courtesy of NASA
Drake’s equation allows us to test alternate
assumptions in a methodical and analytic way
14. The good news is that the math itself
will be done by this presentation
15. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
We start with an estimate
of the number of stars
Photo courtesy of NASA
16. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
We start with an estimate
of the number of stars
Footnote: After completing this
introductory presentation , we
could use Drake’s equation to test
other estimates
Photo courtesy of NASA
such as the “fraction of stars with suitable characteristics”
(not all stars are sun-like, for example)
17. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Fraction
of stars that have
Photo courtesy of NASA
planets
18. We can employ different estimates here to test
the effects if planets turn out to be extremely
common - or if they are comparatively rare
Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Fraction
of stars that have
Photo courtesy of NASA
planets
19. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
What fraction of planets are
HABITABLE
(earth-like, for example)
Photo courtesy of NASA
20. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
What fraction of planets are
HABITABLE
(earth-like, for example)
Not all planets , for example, are
likely to be suitable for life
We want only ‘earth-like’ planets or
Photo courtesy of NASA
others whose conditions allow life to exist
21. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
What portion of habitable planets
are actually inhabited
by LIFE-FORMS of any sort?
Yeast cells
Artwork courtesy of R. Femmer
Anything like these? Marine plankton
22. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
What portion of INHABITED planets
include ‘intelligent’ life?
Photo courtesy John Mosesso, life.nbii.gov
23. Drake’s Equation
N = *
(R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
What portion of INHABITED planets
include ‘intelligent’ life?
Tool-making?
Mathematical?
Photo courtesy John Mosesso, life.nbii.gov
Technological?
On earth, there are
multiple ‘degrees’ of
intelligence
Which organisms would
satisfy the definition we
would use? Chimps?
Dolphins? Only humans?
24. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
What fraction of planets with
intelligent beings will also have
CIVILIZATIONS?
Photo courtesy NASA
25. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
What fraction of planets with
intelligent beings will also have
CIVILIZATIONS?
Photo courtesy NASA
And must they be technologically-
advanced civilizations or not?
26. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
We will be saving
this factor for later
Photo courtesy NASA
28. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Early analyses using Drake’s equation often
employed estimates of the number of stars
in the Milky Way galaxy
Photo courtesy of NASA
29. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Early analyses using Drake’s equation often
employed estimates of the number of stars
in the Milky Way galaxy
For this presentation, however, assume
that an approximate number of
23
stars in the entire universe is something like 1 x 10
Photo courtesy of NASA
This would mean that the value of R* would be
100,000,000,000,000,000,000,000
total stars
30. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
23
If the number of stars present in the universe is 1 x 10
What if PLANETS are RARE and only
1/10th of 1% have planets?
31. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
23
If the number of stars present in the universe is 1 x 10
What if PLANETS are RARE and only
1/10th of 1% have planets?
3
1 out of 1 x 10
…1 out of 1,000…
33. Do the calculation
23
1. x 10
100 000 000 000 000 000 000 000
1000
100 000 000 000 000 000 000
34. Do the calculation
23
1. x 10
100 000 000 000 000 000 000 000
1000
100 000 000 000 000 000 000
1 x 10 23 divided by 1 x 10 3 = 1 x 1020
35. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
So if there are approximately 100,000,000,000,000,000,000 planets
What if EARTH-LIKE planets are rare
and only 1/10th of 1% of planets are HABITABLE?
Photo courtesy of NASA
36. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
So if there are approximately 100,000,000,000,000,000,000 planets
What if EARTH-LIKE planets are rare
and only 1/10th of 1% of planets are HABITABLE?
3
1 out of 1 x 10
Photo courtesy of NASA
…1 out of 1,000…
38. Do the calculation
20
1. x 10
100 000 000 000 000 000 000
1000
100 000 000 000 000 000
39. Do the calculation
20
1. x 10
100 000 000 000 000 000 000
1000
100 000 000 000 000 000
1 x 1020 divided by 1 x 10 3 = 1 x 1017
40. Do the calculation
20
1. x 10
100 000 000 000 000 000 000
1000
100 000 000 000 000 000
1 x 10 20 divided by 1 x 10 3 = 1 x 1017
So this would suggest approximately
100,000,000,000,000,000
planets with conditions suitable for life
41.
42. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Even if, however, there were approximately
100 000 000 000 000 000
habitable earth-like planets
What if development of LIFE on habitable planets is also RARE
and only 1/10th of 1% of habitable planets are hosts to life ?
43. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Even if, however, there were approximately
100 000 000 000 000 000
habitable earth-like planets
What if development of LIFE on habitable planets is also RARE
and only 1/10th of 1% of habitable planets are hosts to life ?
1 out of 1000
45. Do the calculation
17
1. x 10
100 000 000 000 000 000
1000
100 000 000 000 000
46. Do the calculation
17
1. x 10
100 000 000 000 000 000
1000
100 000 000 000 000
1 x 1017 divided by 1 x 10 3 = 1 x 1014
47. Do the calculation
17
1. x 10
100 000 000 000 000 000
1000
100 000 000 000 000
1 x 1017 divided by 1 x 10 3 = 1 x 1014
So this would suggest approximately
100,000,000,000,000
planets with some sort of life
48. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
So if there are approximately
100 000 000 000 000
planets with life-forms of some sort,
What if INTELLIGENT life is a rare occurrence and
only 1/10th of 1% of planets develop intelligent beings?
49. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
So if there are approximately
100 000 000 000 000
planets with life-forms of some sort,
What if INTELLIGENT life is a rare occurrence and
only 1/10th of 1% of planets develop intelligent beings?
3
1 out of 1 x 10
…1 out of 1,000…
50. Do the calculation
14
1. x 10
Artwork courtesy of R. Femmer
100 000 000 000 000
1000
51. Do the calculation
14
1. x 10
100 000 000 000 000
1000
100 000 000 000
1 x 1014 divided by 1 x 10 3 = 1 x 1011
If correct, this would mean approximately
100 000 000 000
planets with intelligent life
53. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
So even if there might exist approximately
100 000 000 000
planets that are home to some form of intelligent life,
What if ADVANCED CIVILIZATIONS rarely develop and
only 1/10th of 1% of planets develop advanced civilizations
Photo courtesy of NASA
54. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
So even if there might exist approximately
100 000 000 000
planets that are home to some form of intelligent life,
What if ADVANCED CIVILIZATIONS rarely develop and
only 1/10th of 1% of planets develop advanced civilizations
Photo courtesy of NASA
3
1 out of 1 x 10
…1 out of 1,000…
55. Do the calculation
11
1. x 10
Photo courtesy of NASA
100 000 000 000
1000
Photo courtesy of NASA
56. Do the calculation
11
1. x 10
Photo courtesy of NASA
100 000 000 000
1000
100 000 000
Photo courtesy of NASA
57. Do the calculation
11
1. x 10
Photo courtesy of NASA
100 000 000 000
1000
100 000 000
Photo courtesy of NASA
1 x 1011 divided by 1 x 10 3 = 1 x 108
58. Do the calculation
11
1. x 10
Photo courtesy of NASA
100 000 000 000
1000
100 000 000
Photo courtesy of NASA
1 x 1011 divided by 1 x 10 3 = 1 x 108
So this would suggest the possibility of
100 000 000
planets with technological civilizations
59.
60. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
This seems very impressive
Think how amazing it would be
if 100,000,000 planets
with civilizations actually exist
61. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Recall, however, this
factor , which we
deferred earlier
Can you guess
what it is?
62. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Recall, however, this
factor , which we
deferred earlier
Can you guess
what it is?
It is
…. time ….
63. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
This factor is
…. time ….
and it is very sobering
because our own planet has had dozens of great civilizations,
but only over the last century do we meet a definition
of “technologically advanced” communicative civilizations
For example, radio telescopes
64. Drake’s Equation
*
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Thus, this factor
represents the
percentage
of a planet’s
lifetime, L
Images courtesy of R. Femmer
that is marked by the presence of intelligent beings
with a technologically-advanced communicative civilization
65. If civilizations
do not begin instantly,
take a long time
to appear and develop,
and do not last forever
and only exist FOR TINY FRACTIONS
of their planet’s total lifetime
66. or for only a tiny
portion of the total
elapsed time of the
universe itself
Photo courtesy of NASA
68. 8
Suppose that somehow 1 x 10 advanced civilizations manage to develop
-7
If, however, they only exist for a 1 x 10
portion of their planet’s lifetime **
Earth is about 4.4 billion years old
Then
1 x 108
= 1 x 101 = 10
7
1 x 10
69. 8
1 x 10
= 1 x 101 = 10
7
1 x 10
Thus, given the estimates
suppositions, and
assumptions that we have
used in this sample analysis
Just ten planets with
technologically advanced civilizations
might exist at
a particular moment in time
70. Employing the estimates
and mathematics used in
our example,
there may be only TEN
other advanced
civilizations
out there somewhere at
this moment in time
77. *
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Footnotes
For convenience, this presentation assumed
a 1/10 th of 1% probability for each factor
in its discussion
But the percentages that one chooses to
assign to each factor can and should be
modified on the basis of humankind’s ever-
increasing knowledge and understandings
For example, solar systems with multiple
planets may not be rare at all, but may be
very common so that the equation could be
run again to reflect a much higher number
of planets
78. *
N *= (R ) ( fp ) (ne) ( fl ) ( fi ) ( fc ) ( L)
Footnotes
On the other hand, many stars are
very different than our sun and may
be unsuitable for sustaining life as
we know it
In that case, the value that that we
assign to factor R* should
probably be adjusted
We could adjust R* downward, for
example, by adding a factor fs to
the equation to incorporate a
“fraction of suitable stars” into our
estimates
79. Footnotes
Many scholars and authors have utilized
and discussed Drake’s equation
A web search of books and other resources
will reward viewers of this presentation
with many additional insights concerning its
implications and applications
Particular credit should go to Frank Drake,
however, and his fellow astronomer Carl
Sagan
80. Made available courtesy of
The Wecskaop Project
What Every Citizen Should Know About Our Planet
Images courtesy of R. Femmer