In August 15 1977 a strange signal from
the constellation Sagittarius was

received by the Big Ear radio telescope
the signal known as the lost signal
reached an intensity up to 30 times
higher than the usual signals and had a
duration of 72 seconds it's name comes
from the note written at that moment by
the person who discovered it Jerry
our Ely collaborator and SETI project a
project for the search for
extraterrestrial intelligence founded by
NASA in 1960 the WHA signal is among all
the strange signals received up to now
the one that has the greatest likelihood
of having been emitted by intelligent
extraterrestrial beings despite its
origin still being uncertainty to this
day in a vast universe 40 billion years
old and containing 500 billion galaxies
science is convinced that there must
exist or must have existed
extraterrestrial intelligence in this
vastness it would seem that there should
be fullness of life out there with this
conviction human beings have searched
for and still search for it incessantly
state-of-the-art radio telescopes
tracked the sky day and night year after
year in search of any sign of
extraterrestrial intelligent life
nevertheless in 2009 everything changing
that year NASA launched the Kepler
satellite into space
thanks to it we have found thousands of
earth-like planets where conditions for
life might be possible this is meant
undoubtedly the total revolution in the
search for extraterrestrial intelligent
life
given the important advances in
astrophysics some scientists believe
that there is a chance of finding
extraterrestrial intelligence in the
next decades seth shostack
astronomer and director of SETI search
for extraterrestrial intelligence
declared before the House Science
Committee of the American Congress that
in a couple of decades we will have
found evidence of its existence the
chances of finding it I think are good
and if that happens it will happen in
the next 20 years depending on the financing a first contact could be
closed the question is do we really want
them to find us what will these forms of
life be like
what will their aims be is anybody out
theregiven the millions of billions of
earth-like planets life elsewhere in the
universe
without a doubt does exist in the
vastness of the universe we are not
alone Albert Einstein 4.5 billion years
ago in the vastness of the universe the
earth our home was formed from the birth
of the universe it took 14 billion years
for human beings to arise just six
million years ago to give us an idea of
the time which has passed until our
first steps Carl Sagan made a time
comparison in which if the age of the
universe was a year the Big Bang would
have occurred on January 1st
on September 8th the Sun would have
formed on September 11th the earth would
have formed and we would have been born
the last day of the year December 31st
at 11:39
how many things must have happened in
other places during the same time
today when we take a look at what we
know about the universe and what we know
about the origins of life on this planet
it leads us to think that the same
things that happened here might well
have happened elsewhere and so life
beyond this planet is quite plausible in
terms of a science that we know today we
see the organic building blocks that are
essential to life on Earth and so the
raw stuff that's necessary for life is
out there the places that life could
live is out there the big question is do
they come together and form a second
Genesis we take up a tiny place in the
immensity of the universe
the Milky Way the galaxy we live in
might have around 100 billion stars
among them our Sun in total it measures
around 100,000 light-years in diameter
maybe there are a million maybe there
are a billion maybe there are a hundred
billion planets in the Milky Way galaxy
that could support life the kind of
planets that earthly life could survive
on how many of them have cooked up their
own life here from one end of the Milky
Way

we an intelligent civilization wonder 

if it's possible that we are alone in all
of this vastness there's just a lot of
real estate a lot of room for life in
space we've now learned that planets are
as common as cheap hotels they're all
over the place
there are a trillion that's a million
million planets just in our own galaxy
if there is no life on any of them then
earth is a miracle a miracle and I'll
tell you this for scientists believing
in miracles is usually not a good
strategy when we think about how vast
the universe is it would be incredible
if there's no other life out there there
are hundreds of billions of stars in our
galaxy alone and there are billions of
galaxies in the universe
if life appears on only a miniscule
fraction of those planets then life is
prevalent throughout the universe that's
why human beings and their enthusiasm
for knowledge and exploration have
started the search for intelligent life
with the hope of sooner or later finding
it are being found by it
Alton is Podesta hi Rita Aaron echoes
Prospero's Eloisa manfully posse
felicidade todos de hecho nada
hasta carcinogen Yeah right oh yes - a
man hollering old Caldecott Naveen
evasion accommodation Aaron aunty
fortunate receiver was na x ma no karate
ramana a neo Kozma was Narayana
Harvick of Ananda awesome mission way
what person they show more closer this
search can be done in two ways tracking
signals that may come from any
extraterrestrial civilization or sending
our own messages into space which may be
received by one of those civilizations
someday active SETI also sometimes
called Betty messaging extraterrestrial
intelligence reverses the roles instead
of passively listening for a signal from
another civilization we send intentional
powerful signals to nearby stars in the
hope of getting a reply backelaborate and comprehensive message to
date the sounds of the earth was
launched into space a moving
introductory message including
everything that human beings considered
that our and extraterrestrial
civilization should know about our
species it was included on a golden
record on each of the Voyager
interstellar space probes launched that
same year from Cape Canaveral as a
golden record on one side there were
encoded music from around the world
greetings and 55 languages a 12-minute
solemn montage of the evolution of life
on Earth and on the other side there
were pictures over a hundred pictures
describing some basic mathematical
principles in the diversity of life and
culture on earth the content of the
recording was carefully chosen by NASA
and a committee chaired by astronomer
and author Carl Sagan
the audio section has a salutation in
English from the UN general secretary
and short messages in 55 languages
welcoming and wishing peace to all forms
of life we thank you he thought is
actually active really
but that one was not the only message
sent
there have been a few symbolic
transmissions to Otherworld the most
famous transmission to another
civilization happened in 1974 from the
world's most powerful radio telescope in
Arecibo Puerto Rico it was a very simple
message
it took three minutes to sand and it
provides a mathematical and scientific
overview of life on Earth
nevertheless the search for
extraterrestrial life is not founded
just on the sending of messages in the
hope of a response someday but on the
development of a search for signals that
may indicate the existence of that
intelligent life SETI
as a scientific exploration actually got
its start within NASA in the life
sciences portion of NASA people were
interested in the question of life
beyond the earth and this program
developed within NASA it launched
actually in 1992 it was called the high
with this goal in 1977 the most  resolution microwave survey in 1993
senator bryan from nevada terminated
nasa's funding for SETI and he
terminated with a vengeance so that NASA
was unable to recover and come back the
next year with another City program so
at that point because we had already
formed a non-profit Institute called the
SETI Institute to help NASA stretch its
funds as it did this SETI work in 1993
we said okay we've got a non-profit
we're just gonna go out and raise money
to do this privately the SETI Institute
is nowadays the main world institution
devoted to the search for
extraterrestrial intelligence it's a
project called SETI the search for
extraterrestrial intelligence
this search is based on the use of radio
telescopes radio telescopes receive
radio waves as we can't go to space
aboard spacecrafts to find that
intelligent life what we look for are
radio signals what we're looking for is
a signal that's at one spot on the radio
dial
just like when you're listening to the
the radio in your car you know you tune
across the dial you hear static
everywhere and then at one spot you're
near and there's a station okay that's
the signal that's produced by a
transmitter somewhere it's not natural
static it's not like a quasar a pulsar
galaxies or hot gas coal gas all those
things in space make radio noise but
it's all over the dial so we look for
signals that are at one spot on the dial
and of course the source of the signal
has to be up in the sky those are the
kinds of criteria we use to know that
even if we don't know what it means we
at least know they're there they're
there on the air
one of the biggest SETI projects started
in 2007 is the Fallon telescope array
which seeks to install 350 antennas to
receive possible messages from outer
space

we designed this

 we went to Paul Allen
and asked him to fund it and he was
generous to fund the first phase of
construction of what we now call the
Allen telescope array it's in Northern
California near Mount lassen the Allen  telescope array has 42 telescopes
someday we hope to grow it to 350 the
Allen project will become the most
powerful instrument in the search for
signals from other civilizations in our
galaxy since it was launched after just
a few months in operation it has been
able to analyze the same amount of area
of the universe as in the last 45 years
of SETI's existence
another of SETI's most famous innovative
projects is SETI at home it was started
in 1999 by astronomers at the University
of California in Berkeley and it uses an
army of millions of amateur Internet
users from home anyone can be part of
this enthralling pursuit the screensaver
analyzes some of the data that comes
from the Arecibo radio telescope in
Puerto Rico up to now more than five
million people from all over the world
have participated and are processing all
of the info captured by the Arecibo
radio telescope the SETI at home project
has grown so quickly that it is the
biggest ever of its kind both projects
Allen telescope array and SETI at home
have been a huge advance in the search
for intelligent light giving hope for
discoveries in the near future
but undoubtedly what has radically
revolutionized and pushed the search for
extraterrestrial intelligent life is the
Kepler mission which is focused on the
search for potentially inhabitable
planets it was launched by NASA on March
6th 2009 and orbited the Sun looking for
extrasolar earth-like planets where life
may be possible Kepler which is a
space-based telescope that was launched
about five years ago is on the hunt for
planets Kepler has found literally
thousands of planets or planetary
candidates it's it's a planet finding
machine the Kepler spacecraft has been a
game-changer in the search for other
intelligence Kepler now can tell us
which stars have planets around them and
which of those stars are earth-like that
means we now know where we can point our
telescopes to look for a twin of Earth
in 2011 for the first time ever
Kepler provided scientists with a census
of the Milky Way for the first time ever
we can calculate how many stars in the Milky Way could have a planet like ours
around a billion so one of the big
triumphs of astronomy in the last two
decades is to show the majority of stars
have planets planets all over the place
there are more planets than stars
according to the data in the near future
millions of inhabitable planets may be
found just in our galaxy what Kepler is
shown is that maybe one in five stars
has a planet which could have liquid
oceans a bit of an atmosphere in other
words the kind of place where you might
want to build you know build yourself a
house right so one in five means that
just in our galaxy there are tens of
thousands of millions of cousins of the
earth that's a lot of real estate this
data is crucial to answering the
question of whether we are alone in the
universe and helping us to resolve some
unknowns of one of the most famous
equations in astrophysics the Drake
Equation which is now of major interest
the Drake Equation is a way to grapple
with all of the issues most central to
determining how many civilizations are
there out there in our galaxy trying to
make contact the Drake Equation looks at
seven independent factors and tries to
put a number on each of them so you
multiply all those up and you come up
with a number that we call in the number
of potentially communicative
civilizations in the Milky Way our star
is the rate at which stars have been
born in the Milky Way galaxy over the
last few billion years so it's a number
that is stars per year our galaxy is ten
billion years old and early in its
history stars formed at a different rate
all of the F factors are fractions each
one must be less than or equal to one F
sub P is the fraction of stars that have
planets n sub E is the average number of
habitable planets in any planetary

system F sub L is the fresh

planets on which life actually begins
and f sub I is the fraction of all those
life-forms that develop intelligence F
sub C is the fraction of intelligent
life that develops a civilization that
decides to use some sort of transmitting
technology and finally L the longevity
factor on average how many years do  those transmitters continue to operate
that is perhaps the most elusive term of
the Drake Equation as we look into our
own future we wonder will we survive as
a technologically adolescent
civilization will we last long enough to
make contact that is the big unknown the
Drake Equation includes a series of
terms whose value we can't know exactly
it's just a fantastic framework with
which we can organize our ignorance
because you can't solve the equation
there are no right answers to that
equation not yet as we shift into the
more biological and cultural terms of
the Drake Equation we move into areas
where we're uncertain but during the
last few years we've seen how exoplanets
have arisen in front of our eyes thanks
mainly to the Kepler space satellite
when Frank Drake first wrote down the
Drake Equation back in 1961 he put his
own personal estimates into each of
those factors and came up with a number
his estimate which was ten thousand so
within the Milky Way galaxy of a hundred
billion stars
he thought ten thousand of those stars
might host technological civilizations
what do we know now that we didn't know
in 1961 well we know one or two of those
terms a little bit better and they kind
of agree with the optimistic estimates
that were made 50 60 years ago there are
other estimates that are extremely
pessimistic there's only one and it's us
Carl Sagan had a number that was
more optimistic he said probably a
million was his guess we think we know
that our star and NCB are both numbers
that are closer to 10 then say to one
and all the F factors are less than 1
some of them may be much less than 1 but
of all these unknowns the biggest
unknown is Kell so perhaps the most
useful version of the Drake Equation is
simply to say that n is approximately
equal to L the information in this
equation is very clear unless L is large
n will be small and these are estimates
just for our galaxy but we don't have
estimates just for our galaxy but for
the visible universe
this fact multiplies the chances for the
existence of extraterrestrial intelligence the Hubble Space Telescope
has given us an approximate calculation
of the total number of galaxies in the
Bible universe 100 billion so we can
calculate the number of earth-like
planets in the visible universe a
trillion earth-like planets the universe
is 14 billion years old so there has
been time enough for intelligent empires
to arise and possibly fall
it would be miraculous if no other
advanced civilization anywhere had ever
existed it's just a matter of time until
we find them
radio telescope technology is becoming
more and more advanced and some
scientists believe that the first
evidence will be found in the next
decades so far we've looked at little
over ten thousand stars very carefully
with the Allen telescope array in the
next couple of decades that'll be a
million stars and by the time you've
looked at a million stars that's a
reasonable number to find intelligent
life if it's really out there in fact
people like craig Venter and Daniel
Cohen have said 20th century was the
century of physics 21st century is going
to be the century of biology but my
colleagues and astrobiologists and young
scientists are saying yes the century of
biology on earth and beyond this coming
century this 21st century could well
provide us with evidence of life beyond
Earth and a biochemistry that's
different from the only one we know
the chance of an imminent discovery
brings with it a controversial question
what will the first contact be like what
could you minh being say to another
intelligence species what introductory
message can we compose about human
beings that species that it habits one
of the edges of the universe and who
have developed enough to wonder if there
is anyone else out there or to try to
find them there should be a deliberative
process to think about how we want to
present ourselves to other worlds and
that is a dynamic conversation that
we're having now in the south and in the

science community should 

we transmit if
we do who should speak for Earth what
should they say in what language ho it's not a simple task to ponder a first
introduction to an extraterrestrial
intelligence and the even more
complicated question of how to compose
that message to make it understood how
we would say something meaningful to
another civilization it is going to be
one of the most tremendous intellectual
challenges humankind has ever faced
composing a message that can be
understood by aliens will be extremely
difficult and conversation may be
impossible in order to make contact with
another civilization and truly
understand them we have to find a
language that any scientist who is
engaged in SETI anywhere in the galaxy
will understand this is what's called
active SETI or Metis messaging to
extraterrestrial intelligence if you can
build a radio transmitter anywhere in
the galaxy you have to know that two
plus two equals four and so it's basic
mathematical principles like that that
we use as the foundation for a language
to communicate with extraterrestrials in
terms of the message content how it
should be sent and what it should say
what would we say about
ourselves and what are efficient
encoding schemes and how do we provide a
tutorial so that they can figure out
what the scheme is my suggestion is to
send the internet right send so much
information that they can look through
it and find pictures videos sounds text
of course and they'll be able to
understand its are like the
hieroglyphics several messages have
already been sent to space and we hope
to receive an answer someday the first
sent message was attached to the Pioneer
10 space probe launched by NASA from
Cape Canaveral on March 2nd 1972 a
golden anodized aluminum plate designed
by astronomers Carl Sagan and Francis
Drake was affixed to the probe it was a
kind of an interstellar message in a
bottle
on it drawings of two human figures
appear one feminine and one masculine
with the image of the spacecraft behind
them to show the proportion of the human
silhouettes our address in the universe
was also included as well as a scheme of