ever since even the fourth century BC and beyond I imagine there's been an
interest in the possibility of life elsewhere the Greek philosopher
metrodorus of Chios was very much interested and thought that it would be
very foolish to think that with all the many possible worlds in the universe
that there would be only life on this planet Lucretia later on first century
BC was of a similar opinion it was only with the rise of Ptolemaic X
understanding of the universe that people started to think of the universe
it's earth centered and that was a later on phenomena and not necessarily
prevalent in early Greece as a result of Ptolemies ideas in the Dark Ages in
Western civilization it was considered that earth was the center of the
University was the only place that life existed the later on that was overturned
by the ideas of Copernicus and Kepler those that followed since the earliest
of times man has been interested in the heavens having been fascinated by the
countless points of light that sparkled in the darkness of the evening skies one
of these had a reddish hue to it and was known by several names depending on
where one was many of the ancients named the planet we call Mars after their God
of War due to the planets reddish hue which reminded them of blood in fact the
nickname that the Red Planet comes from this as does the notion that possible
Martians would be warrior like
with Galileo's invention of the telescope in 1609 the first clear look
at this the fourth planet became possible early astronomers believed that
the Martian surface was similar to Earth's the first telescopic drawings of
Mars showing distinct changes in surface appearance were made by Christian
Huygens in 1659 he observed that the Martian polar icecap seemed to wax and
wane and dark patches seemed to appear on the surface of Mars these
observations led to the idea that Mars was indeed a habitable world similar to
our own earth 18th century clouds had dark areas that people thought were seas
it had a time of day was very similar to the earth and so people imagined it to
be like this and so they imagined that there was life there and this the
prospect of really a life was as I mentioned previously reinforced by these
observations of canals however as during early earlier this
century it became clearer how as we understood the conditions on Mars better
life in 1877 an Italian astronomer Giovanni Schiaparelli observed lines on
the Martian surface and called them Canali the English translation of Canali
is channels or grooves these channels were mistakenly called canals in English
and the name stuck of course canals would infer that some
type of intelligent life form on Mars was capable of building these structures
in 1879 Schiaparelli reported seeing double lines of Canali he came to
believe that these finale were rivers on the surface of Mars a natural phenomenon
others continue to think that the Canali were artificial that is to say
constructed by some light form later on shepper le the Italian astronomer made
observations of Mars and in trying to make sense out of the visual image he
saw of Mars on one of the closer opposition's the word Canali came into
use because he thought he saw straight lines on the surface this was seized
upon by Percival Lowell and he wrote a book in the 1890s that described the
possibility of a Mars that would have intelligent life water but a dry planet
in general so I need to get the water down to the presumably more
agriculturally inclined central parts of the planet first of all while maintain
this interest in a living and civilized Mars until his death in 1916 and of
course his ideas were seized upon and made popular for a lot of us by Edgar
Rice Burroughs who's Barsoom series that was fascinating in a lot of fun in a
popular sort of way and I got people's imaginations turned up about the ideas
of civilizations on Mars dying civilizations and recurrent
civilizations and I think that a lot of that stayed in the public mind certainly
was something that I found of interest later on we found that Mars was a much
different place than shepper le and Percival Lowell had imagined the
American astronomer Percival Lowell was another who saw the Canali
and believed them to be artificially created he made his observations with a
variety of telescopes in different parts of the world starting in 1896 Lowell
wrote the first of his three books about Mars there's been a long-standing
interest with Mars and with life on Mars and I think it traces back to the early
telescope observations when people finally started pointing telescopes at
the planets they noticed that Mars unlike all the other
had distinct seasonal cycles very similar to Earth's it had white polar
caps which shrank and grew with the seasons it had dark spots on the surface
which seemed to come and go with the seasons like vegetation and it was this
similarities between Earth and Mars this superficial similarity but I think was
the spark that first started this interest in life on Mars and the notion
that there was civilizations on Mars as well and then I think all the subsequent
observations in some sense culminating with Percival Lowell's work looking for
canals on Mars and the perception that there were canals and that was an
evidence of human civilization like civilizations all that has tended to
reinforce the notion that Mars was the planet that was the most like earth
better information about Mars and its surface came with the development of new
technology the first breakthrough came in 1964 when NASA's Mariner 4 spacecraft
flew by Mars at a distance of nine thousand eight hundred forty-four
kilometers Mariner four returned 22 images of Mars including some which
showed impact craters on the surface and caused much comment among planetary
scientists of the time the images Mariner 4 returned gave us an image of
Mars that was totally different than expected
it wasn't until late 1969 with Mariner six and seven that we got a clearer look
at the Martian surface these two flybys gave scientists hundreds of images and
showed many details of the surface that were once again totally unexpected
the imaging showed a planet start and lunar like in appearance with craters
and vast featureless areas also seen was chaotic terrain unlike
anything seen here on earth around the moon craters ranging in size from 500
meters to 500 kilometers in diameter was seen after we've started to fly by Mars
with spacecraft we found that Mars was a much drier place than it ever had been
conceived of before and also one where a very low atmospheric pressure less than
1% of that of the year total surface area of Mars is approximately that of
the earth dry land surface so it's a fairly large planet in terms of
possibilities and as a separate world anything you say about any particular
place on Mars may not pertain everywhere on Mars a 4th Mariner mission Mariner 9
was successfully launched on May 30th 1971 the spacecraft was inserted into
Mars orbit in November of 1971 and functioned for 349 days returning almost
7,000 images when Mariner 9 first reached Mars an
intense dust storm had obscured most of the Martian surface so scientists used
the opportunity to study the Martian moons Deimos and Phobos Mariner 9
eventually mapped over 85% of the Martian surface with images having a
resolution of approximately one kilometer imaging returned from this
mission gave scientists the first really comprehensive look at the red planet
other experiments on board Mariner 9 told scientists that Mars was a very
cold planet and that the Martian atmosphere was about 1% as dense as the
Earth's atmosphere at sea level the real dramatic change came in 1975 when when
an orbiter was put allowed around Mars began to systematically look at the
entire planet and it just revealed a fascinating place with huge volcanoes
vast canyons enormous dry riverbeds sand dunes just an incredibly very variable
planet and particularly fascinated with all these indications that water had
flowed across the surface and some of that some of the features really quite
startling because they were wrong now dry riverbeds suggestion of large
floods and these floods were an enormous magnitude they would have had discharges
a hundred times at discharge at present Mississippi of course just lasted a
short time but as a consequence people began to rethink about what Mars how
Mars might have formed in what conditions were like past many other
features on Mars were seen for the first time
in addition to olympus mons one of the largest known volcanoes in the solar
system there were vast valleys on the surface of Mars as well as canyons one
of which is much longer and deeper than the Grand Canyon in the alleged States
this Martian abyss Valles Marineris extends over 2,000 kilometres other
formations and deposits seem to indicate that long ago in Martian history there
were large amounts of water present on the surface of Mars Mars was still an
enigma to scientists and researchers after Mariner 9 they wanted and needed
to know much more about Mars specifically whether or not there was or
had been life there so another unmanned mission to Mars was
in the works viking vikings 1 and 2 were launched from Cape Kennedy in the summer
of 1975 and reached Mars in the summer of 1976 the primary objectives of the
spacecraft were to safely land on the surface of Mars and to attempt to
determine if there was some type of life on Mars even now or in the past the
Mariner missions did not tell scientists if there was life on Mars and in the end
Viking did not conclusively answer this question either the Viking spacecraft
each consisted of two separate spacecraft there was an instrumented
orbiter section which remained in orbit above Mars taking readings and
measurements taking pictures and acting as a relay satellite for the Viking
landers these Landers were miniature
laboratories the goal of the Viking project was the exploration of Mars and
we had had missions that went to Mars before but the goal of the Viking was to
land spacecraft on the surface and actually explore in situ what Mars was
like it was like being on Mars we actually had experiments that one would
do if one of us were lucky enough to be landed on on the planet and dug up
handfuls of Mars and had a little laboratory there it was fundamentally
what what Viking was all about we used two spacecraft to do that and the
spacecraft that was a lander this base craft that was in orbit
it was kind of like a mother and a daughter the mother was the one that
received the information and did a little investigation on its own and the
lander was primarily used to to do the kinds of things that if we were having a
field trip on Mars we would have sent an exploration party up to Mars to do that
kind of experiment they involved meteorology they involve biology they
involve chemistry they involved geology of course the biology was a predominant
predominant question we had because that was a kind of the bellringer but
nevertheless did the whole point of the Viking was to explore in breath what
Mars was was like and how similar or how different it is from the earth the
Viking spacecraft consisted of two parts an orbiter that was placed into orbit
around Mars who carried the daughter ship but was then allowed to descend to
the surface of the planet the orbiter consisted of a large
spacecraft with very large solar panels so that it could go absorb the sun's
energy to burn to electrical power and be run the orbiter was placed into
elliptical orbit around Mars the periapsis of your client list was about
1500 kilometers the a box is hinted orbit was trimming about 30,000
kilometers imagine this orbital now passing over a landing site and it's the
distance of about 1500 kilometers trying to take pictures of a landing site that
was no later going to be going to be used for the daughter ship the lander
which was folded up like a chrysalis of a butterfly
would be later landing by descending to the surface the descent of the surface
was tricky because the Mars atmosphere was just thin enough to bring you up and
not thick enough to to slow you down and so there was this unique problem of a
landing system that wasn't just on a parachute in fact we had three braking
systems on Mars once down into the Mars atmosphere a person is popping this was
no ordinary parachute this is a parachute to Hitler slow the spacecraft
down dead at Mach and about box for parachute got us down to within about
100 kilometers and then a retro rocket system was used retro rockets were
firing the Rockets down against the mileage surface to slowly slow the
spacecraft found in combination with a radar to tell us how far we were from
surface and allow this spacecraft to descend to the surface the very last
moments would be like jumping off a small table to be settled on up to the
Mars atmosphere and protect those badly decided against removes from from our
crashed
the first Lander was originally scheduled to set down on the surface on
July 4th 1976 in honor of America's Bicentennial however when the spacecraft
reached Mars and began imaging the proposed landing sites the scientists
saw a younger and more dynamic planet than they had expected after two weeks
of studying the images returned from Mars a new landing site was selected and
the Viking one led is set down on the cry see plenty ship on July 20th 1976
the Viking two Landers safely soft landed on the intopia plantation on
September 3rd 1976 the selection of the landing sites was one of the more
controversial issues of the Viking missions the biologists wanted an area
that would be the most hospitable to life and the landing team wanted to site
most conducive to a safe landing as soon as the lander was down onto the surface
there were two things done one the well-being of the spacecraft think about
you're trying to land some kind of an instrument any worse first thing to do
is to make sure that the system is working
elevates the the antenna that talked back to the earth takes measurement
temperature measurements to make sure that the spacecraft is alright a kind of
housekeeping maneuver there most of the most important piece of scientific data
to come back would be the first picture and the very first picture pointed down
to the foot pad to make sure that the instruments were stable at the
spacecraft was stable and also to see what the Martian surface was like I will
never forget that first evening when we first saw the first pictures coming back
Big Five bit line by line sweeping across the Mars surface and seeing for
the first time that it was a surface that was pre-major from there in the
sense that looked a little bit like like some traditions we've seen of the earth
and it wasn't like the moon at all there were rocks in the circles that were
there features to the surface you didn't get a horizon until the second picture
first just to say it's sort of like looking
down at your own foot if you stepped onto a brand new planet and said what is
it like on this planet in time the other experiments were successfully activated
and the results were anxiously awaited here on earth scientists were elated at
this the first opportunity to look for life on another planet in situ but data
from the experiments on the surface of Mars was inconclusive
additionally the meteorology packages showed Mars to have an extremely cold
and hostile environment to life as we know it here on earth the three biology
experiments were designed to detect activity of microorganisms as we
understand them if there were any present in the Martian soil that Viking
gathered for testing these experiment packages measured a gas exchange with
the surface sample for both the incorporation and release of radioactive
carbon-14 in one experiment immediately after heating and humidifying a soil
sample with it flex nutrient oxygen was detected about
15 times as much oxygen as is known to be present in the Martian atmosphere was
released this result is now thought to have been caused by a chemical reaction
between the soil sample and the nutrient solution as opposed to an indication of
life but at the time and until all the data returned had a chance to be
reviewed analyzed and reanalyzed no one could say for certain what this
reaction meant in a third experiment that we kind of laughingly called the
chicken soup experiment we actually tried to grow some organisms we took a
mixture of delicious terrestrial ingredients all sorts of vitamins and
minerals extracts amino acids and sugars all the goodies that you would use if
you were going to grow up some organisms and the idea was to inoculate the sample
with these goodies
now in the experiment we had a novel of first stage before we actually
inoculated this happened we wanted to humidify some terrestrial organisms that
formed spores are known to died as a result of the ingestion of water so the
idea is do we do with spore farmers on the earth we first humidified just
expose it to water and then finally grow up your business in the case of that
experiment we had a great surprise instead of the first humidification
having no result which was what we would see here on earth we saw enormous
quantities of oxygen that came out of the sample for reasons that at the time
were very confusing to us we saw this release of oxygen not at all which you
find here on the on the earth finally after some thought we figured
out what that oxygen was we finally figured out that Mars surface of Mars
has some peroxide as though there were kind of bleach or something spilled on
the surface these were a little like hydrogen peroxide although there's no
hydrogen peroxide acknowledged it's proudly iron peroxide a peroxide is
something that's known to give up oxygen and when you add water to a peroxide
this oxygen is released a kind of self sterilizing surface in a way we don't
know that that's the fact on Mars but that's a possibility
and in fact it explains what happened in this second experiment in the second
experiment where we had added the growth media probably what happened is the
peroxide on Mars reacted with the growth media and the least some of the carbon
dioxide as though it were being broken down by organisms a kind of chemical
reaction so in fact the two experiments blended together so that the results of
the third gas exchange told us something about the answer to
the second the label release experiment some of the people who have been
interested then on life on Mars participated in the Viking mission in
1975 launched 1976 landing where they sifted the very fine surface material
and put it into what was called the Viking biology package and conducted a
series of experiments looking for life on Mars the results of those experiments
were equivocal there were some reactions in the experiments that were consistent
with life some that were inconsistent with life and generally the tie vote got
ascribed to a device called a guest from at ography mass spectroscopy device says
the GCMs and the GCMs showed no evidence for organic material in the soil it
wasn't able to get you know final evidence that none existed on Mars and
it was only looking at material taking from about the first four inches of the
surface but because there was no organic material detectable by the GCMs it was
thought that the reactions that were seen in the Viking biology package were
inconsistent with life as we know it at present most scientists and researchers
discount the theory that intelligent life was ever present on Mars there are
those however who believe that at some time in Martian history there was
intelligent life on the planet this minority claims that the features seen
in certain images returned by the Viking orbiters of the Martian surface show
signs of past intelligent life there they feel that some of the features seen
in certain images are actually monuments left behind by a past Martian based
civilization for us to find and use a beacon a beacon to home in on to find
the remnants of this proposed civilization although not endorsed by
NASA Richard Hoagland space author and lecturer because of some of the Viking
images suggest the past intelligent civilization on Mars a set of
photographs taken on the morning of July 25th 1976 came in through the various
channels back to the computers of JPL and then to those of us who were
gathered at JPL to witness this historic first landing the spacecraft along
another planet and one of those photographs showed a mile-long 1500 foot
high Mesa in the cydonia region the northern deserts that was literally out
of place it did not belong it cried out for explanation if only for reassurance
that it could not be real because the object looked like a humanoid face it's
highly speculated there's no question about it that there's an interesting
feature on Mars that appears to look like a human face I think that this
speculation is all very much interesting to sell newspapers but there's not a lot
of scientific credibility in it unfortunately we don't have enough data
to address the question of why this happens to look like a human face but I
would suggest that most one of the most adaptive features that humans have is
the ability to recognize human faces in order to envision that those monuments
were created by a civilization an intelligent civilization
you really need to extrapolate our knowledge of evolution and biological
processes enormous ly somehow you have to envision that life started on Mars
and it evolved very rapidly and persisted even in the face of adverse
conditions as the planet got colder and drier it would have been difficult for
life to have continued somehow to imagine a civilization there would have
required that it did so the evidence of the monuments and the faces is very
interesting I think they are interesting geological features some of the people
who claim that the monuments on Mars and the face
on Mars are indeed artifacts from an extinct civilization do not claim that
intelligent life or the life forms that may have constructed these alleged
structures evolved on Mars rather they say that the beings may have come from
another planet and of a solar system or another galaxy the idea that this
supposed complex of structures on Mars are a construct stems from their
geometric alignment we have found other provocative sets of objects and the
important thing is sets because of the resolution we're looking at 50 meters
100 meters you're not going to see structures of comparable size to those
on earth you're seeing much larger objects and the only indicator that they
are made by intelligence is their relative geometric placement relative to
other objects Carl Sagan who has some credentials for four pronouncements in
this area has said that on earth the first indicator of intelligent
design is the geometric regularity of our constructions taking that rule of
thumb and applying it to another planet like Mars if we see a set of objects in
a very particular geometric configuration the suspicion is raised
just the suspicion then maybe we should look closer unfortunately we only have
really good coverage in Cydonia we do not have dual sets of pictures taken to
two different Sun angles like we do in Cydonia in other places both sides do
agree on two points first the face is indeed a very fascinating image but what
it is or means is still open for speculation and second that the Mars
Observer spacecraft should definitely be used to return
higher resolution images and more complete imaging than anything Viking
sent back the ultimate answer to the question of where these features made by
some life-form were caused by natural processes on the Martian surface awaits
us but until a human sets foot on the surface of Mars and can examine the
evidence firsthand we will have to continue to be satisfied
with robotic exploration
you
you
I hid here about the only
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