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There is Alien life in the Universe

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Voting Style: Open Point System: 7 Point
Started: 6/27/2013 Category: Science
Updated: 5 years ago Status: Post Voting Period
Viewed: 1,477 times Debate No: 35119
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Are there Alien life forms anywhere in the universe outside of our Planet?

To clarify, in this Debate I (Pro) shall be arguing that Alien life forms do exist within the Universe. You (Con) shall be arguing that Aliens, in actuality, do not exist.


Aliens: Life forms that live outside of Planet Earth

Universe: All existing matter and space considered as a whole; the cosmos.


1. Acceptance only
2. Arguments
3. Clash
4. Closing Summaries

Good Luck!


I will accept this debate and make the con case. Good luck, let's have a good debate.
Debate Round No. 1


I'd like to start by thanking my opponent, I look forward to a great debate. Now the formalities are completed, I shall begin.

Clarity of Statement and Debate

To start with, I feel it's important that the statement “There is Alien life in the Universe” is interpreted as intended and therefore, not misconstrued. To clarify, I shall debate the view point that it is more probable than not some sort of Alien life form(s) do exist outside of Planet Earth's Atmosphere. By Life forms I mean any living organism, from the most minute extent, to the most mammoth extent. To put it simply, any living thing.

In this debate, I am regarding the entirety of the universe, excluding Planet Earth and its Atmosphere, as all that is, and therefore, all that exists. Exists - Have objective reality or being.

I would also like to point out that due to the fact none of us will be able to offer a definitive answer, this debate, therefore, should be based on probability. The side that is able to prove to a greater extent there is a higher probability that either aliens do, or do not exist as specified in the given context should win this debate.

Contention 1: The sheer magnitude and probability

In our Galaxy alone, the Milky Way, we've confirmed there is approximately 300 billion stars. The piece of information below states:

"According to astronomers, there are probably more than 170 billion galaxies in the observable Universe, stretching out into a region of space 13.8 billion light-years away from us in all directions.

And so, if you multiply the number of stars in our galaxy by the number of galaxies in the Universe, you get approximately 1024 stars. That’s a 1 followed by twenty-four zeros.

That’s a septillion stars. But there could be more than that."

There is no debating the unfathomable vastness of the stars, planets and the universe, this, I'm sure you'll agree with. Now we move on to how many
habitable planets there are,

For this segment, I will use research and understanding to demonstrate that there is, in all likelihood, Alien life in the universe.

For Carbon-Based life forms like here on Earth to flourish on any other planetary-mass object, with the exception of other energy sources, that object/planet must be within the
"habitable zone" or Goldilocks Zone, defined here:

"In astronomy and astrobiology, the circumstellar habitable zone (CHZ) (or simply the habitable zone) is the region around a star within which planetary-mass objects with sufficient atmospheric pressure can support liquid water at the surface."

For this segment I shall momentarily rule out any Non Carbon Based Life and proceed only to highlight that carbon based life forms, outside of Earth, do exist.

To do this I will take the analyzed data from Kepler, the
600 Million Dollar Spacecraft launched in March 2009, kicking off a 3.5-year mission to determine how common Earth-like planets are throughout the Milky Way galaxy.

"Based on Kepler's findings, astronomer Seth Shostak estimated in 2011 that "within a thousand light-years of Earth", there are "at least 30,000" habitable planets. Also based on the findings, the Kepler team has estimated that there are "at least 50 billion planets in the Milky Way", of which "at least 500 million" are in the habitable zone ...

The JPL astronomers also noted that there are "50 billion other galaxies", potentially yielding more than one sextillion "Earth analog" planets if all galaxies have similar numbers of planets to the Milky Way."

So far Kepler has found 48 Earth-Like planets in the Goldilocks zone, where carbon-based life could exist like here on Earth.

Ruling out this data and assuming there's not even one micro-organism existing on one of those 500 million planets in the habitable zone of our Galaxy is silly. Ruling out the existence of at least one micro-organism existing on some planet/planetary-mass in the entire universe? Now that's crazy.

Contention 2: Non Carbon Based Life

It is important not to be blind sighted and to remember that life on Earth is only a particular instance, here, life is carbon-based, but scientifically, it is easy to believe, given the vastness of the Universe that other types of life may exist that are in fact not carbon based, Hawkings said this during his lecture, Life in the Universe:

"What we normally think of as 'life' is based on chains of carbon atoms, with a few other atoms, such as nitrogen or phosphorous, We can imagine that one might have life with some other chemical basis, such as silicon, but carbon seems the most favorable case, because it has the richest chemistry."

Such probable variations in the potential make up of diverse life forms make the potential existence of Aliens far more likely. Because now, the "habitable zone" or Goldilocks Zone, defined here:

"In astronomy and astrobiology, the circumstellar habitable zone (CHZ) (or simply the habitable zone) is the region around a star within which planetary-mass objects with sufficient atmospheric pressure can support liquid water at the surface."

Is no longer necessary to take into account when comprehending the probable existence of Non-Carbon Based life.

"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."

Despite the obvious, which is that there is likely to be lesser ammonia/ammonia-water dependant life forms compared to Carbon-Based, it's logical to conclude, given the vastness of the universe and planetary-mass objects, there are some that support this type of life.

Here on Earth alone, we have discovered a type of bacteria called
GFAJ-1 which disposes of current conceived conventions. It is unlike anything currently living in planet Earth. It's capable of using arsenic to build its DNA, RNA, proteins, and cell membranes. Arsenic is an element poisonous to every other living creature in the planet except for a few specialized microscopic creatures. This life form is able to use Arsenic in the place of phosphorus, which proves there are variations on a life-forms buildings blocks.

Take this fact, there is at least one life form on Earth that breaks down the previously thought building blocks of life's conventions. You can deduce from this that variations in fundamental life-from structure exists, definitively. If you then apply this knowledge to the entire Universe, yet fail to accept it is probable a life-form exists with different building blocks from us on another planet, you've ignored the fact one exists on this Planet, let alone on one of the Planetary-masses circling one of the trillions upon trillions of stars in the observable universe.

Brief Conclusion:

It is fact that other Earth-like planetary-masses exist in habitable zones like our own in correlation with the sun. We have found them.

It is fact that life-forms do not strictly adhere to our exact structure as previously thought so therefore could exist in an even higher percentile of the universe than just Carbon-based life forms.

Based on the abundance of evidence and facts it is astronomically more probable Aliens do exist than don't.

I ask my opponent to put forth his Argument this round and address his discrepancies with mine in the fourth. Thank you.

Sources: Stars habitable planets



Mouse1 forfeited this round.
Debate Round No. 2


It appears Con has de-activated his account. If anybody else would like to debate this with me, please message me, or comment, thanks.


Mouse1 forfeited this round.
Debate Round No. 3


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Mouse1 forfeited this round.
Debate Round No. 4
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