Some leading astronomers are quite confident that mankind
will make contact with intelligent alien life within two decades. The search
for extraterrestrial life will leap forward next year when NASA launches the
Kepler space telescope. The instrument will be constantly scanning the same
100,000 stars over its four-year mission with the exciting objective of
discovering Earth-sized planets in the habitable zones around suns.
This will allow SETI to home in on where the odds of life
are possibly greatest. Currently, SETI’s mission to find life on other planets
is like trying to find the proverbial needle in a haystack. But now, whenever
Kepler identifies planets most likely to sustain life, the team at SETI will be
able to focus in on those solar systems using deep-space listening equipment.
This will be a huge upgrade from their present work of randomly scanning the
outer reaches of space for some kind of sign or signal. Also, upping the ante,
is the recent discovery of Earth-like planets outside our solar system, which
has led astrophysicists to conclude that Earth-like planets are likely
relatively common in our galaxy.
"Everything has caused us to become more optimistic,"
said American astrophysicist Dr Frank Drake in a recent BBC documentary.
"We really believe that in the next 20 years or so, we are going to learn
a great deal more about life beyond Earth and very likely we will have detected
that life and perhaps even intelligent life elsewhere in the galaxy."
However, some astrophysicists have warned that we humans may
be blinded by our familiarity with carbon and Earthlike conditions. In other
words, what we’re looking for may not even lie in our version of a “sweet
spot”. After all, even here on Earth, one species “sweet spot” is another’s
species worst nightmare. In any case, it is not beyond the realm of feasibility
that our first encounter with extraterrestrial life will not be a solely
carbon-based occasion.
Alternative biochemists speculate that there are several
atoms and solvents that could potentially spawn life. Because carbon has worked
for the conditions on Earth, we speculate that the same must be true throughout
the universe. In reality, there are many elements that could potentially do the
trick. Even counter-intuitive elements such as arsenic may be capable of
supporting life under the right conditions. Even on Earth some marine algae
incorporate arsenic into complex organic molecules such as arsenosugars and
arsenobetaines. Several other small life forms use arsenic to generate energy
and facilitate growth. Chlorine and sulfur are also possible elemental
replacements for carbon. Sulfur is capably of forming long-chain molecules like
carbon. Some terrestrial bacteria have already been discovered to survive on
sulfur rather than oxygen, by reducing sulfur to hydrogen sulfide.
Nitrogen and phosphorus could also potentially form
biochemical molecules. Phosphorus is similar to carbon in that it can form long
chain molecules on its own, which would conceivably allow for formation of
complex macromolecules. When combined with nitrogen, it can create quite a wide
range of molecules, including rings.
So what about water? Isn’t at least water essential to life?
Not necessarily. Ammonia, for example, has many of the same properties as
water. An ammonia or ammonia-water mixture stays liquid at much colder
temperatures than plain water. Such biochemistries may exist outside the
conventional water-based "habitability zone". One example of such a
location would be right here in our own solar system on Saturn's largest moon
Titan.
Hydrogen fluoride methanol, hydrogen sulfide, hydrogen
chloride, and formamide have all been suggested as suitable solvents that could
theoretically support alternative biochemistry. All of these “water
replacements” have pros and cons when considered in our terrestrial
environment. What needs to be considered is that with a radically different
environment, comes radically different reactions. Water and carbon might be the
very last things capable of supporting life in some extreme planetary
conditions.
At any rate, the odds of there being some type of life
somewhere out there are good. As for intelligent life, well, that will depend
on the definition of intelligence. There are a lot of other intelligent species
here on Earth besides humans, that we don’t generally regard as such. In spite
of many Star Trek episodes to the contrary, the odds of alien life forms having
evolved to talk, look and act exactly like super hot humans are slim to none.
If life is out there, it will have evolved according to it’s particular niche
in the universe and will likely be quite foreign to us in the way it looks,
communicates and thinks. We might not even be able to recognize hypothetical
life forms as alive in the sense that we understand life. In fact, it would be
more “miraculous” if we could effectively communicate with extraterrestrial
life than to find that it exists. From that perspective, even if there are
other life forms out there, we’d still be alone in the universe. Of course,
that doesn’t mean we shouldn't look for the answers.
Posted by Rebecca Sato.
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Source links:
http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_article_id=524673&in_page_id=1965
Excellent article .
I agree with Dr.Drake's equation and I am sure that the new 'planet finder space telescope' will help those at SETI.
However and again it is a matter of different approaches to comms that may and could also in the future impede a true contact.
We (by definition) have NO idea about HOW these civilized extraterrestrial races communicate....are they using radio and microwave signals like we do ????
Who says this ?????? and on what basis this inference is generated ????
Anyway regards to Dr. Drake.
Posted by: claudio | August 25, 2009 at 09:10 AM
Within the next two decades - I think that's somewhat optimistic.
Again, what if the extra - terrestrials think that we're just too primitive, backward, or even INSANE to bother contacting ?
AND AGAIN, there might be some Extra - Terrestrials who are highly civilized, but maybe in a version of the Earth's Roman or Greek or Egyptian Empires, or maybe at the beginning of something equivalent to the American or European Industrial Age, & unable to make contact or explore space.
Posted by: EvilCosmicMonkeyfrom Knoxville | August 25, 2009 at 01:06 PM
I believe that if we do make contact with an alien race, communication with them will be next to impossible because of enormous psychological boundaries. I mean their psychology would be immensely different to ours. We can't even communicate effectively with other species on our own planet.
Posted by: Moi | January 20, 2010 at 12:16 AM
Has anyone really been far as decided to use even go want to do look more like?
Posted by: Bobby B. Bobberson | December 30, 2010 at 01:28 PM