Communication with Alien Civilizations

SETI, whose job it is to find proof of alien civilizations, has yet to find any alien civilizations. The methods employed by SETI has so far focused on trying to receive messages via the EM spectrum for alien communication.

So far, SETI has been looking for messages from other alien civilizations in the form of "Anybody out there?" However, it may soon be looking for any signs of other alien civilizations by attempting "to eavesdrop on stray signs of intelligence leaked accidentally into space by other civilizations", says Steve Nadis in his Astronomy article titled Eavesdropping on E.T.: Could Changing Channels Tune Into Alien Civilizations?.

There is a quiet zone in the EM spectrum between 1 and 10 GHz. Fewer objects in the universe naturally transmit in that frequency range. If other alien civilizations know this, they may choose to intentionally transmit signals at that level. However, it may be easier to look for signals that alien civilizations naturally put out. The problem is that there is so much background noise at other frequencies, both from the Universe and Earth itself (our own civilization). Some scientists hope that a new radio-telescope coming on line in Australia called Murchison Wide-Field Array (MWA) will allow them to find anomalies that may be leaked transmissions of other alien civilizations. Though MWA is really meant to study the end of the Universe's Dark Ages (when stars began to form), it will also be able to find transient signals that may be signs that something else is out there.

Earth has been broadcasting its presence since the 1920's. Maybe another civilization has been doing the same for much longer? We will soon see.

Reference: Astronomy May 2008, Eavesdropping on E.T.: Could Changing Channels Tune Into Alien Civilizations?, by Steve Nadis

Related articles

• Video: What Would Trees Look Like On Other Planets?
• Predictions of Evolution of Alien Life
• Communicaion with Alien Civilizations
• Odds of Humaniods Evolving again
• Part 5: Blue Plants
• Part 4: Silicon Life
• Part 3: Arsenic Life
• Part 2: Exotic Amino Acids
• Part 1: Mirror Life

Possible types of Alien Lifeforms (Part 5: Blue Plants?)

It has been sited by physicists that while photosynthesis on Earth generally involves green plants, a variety of plants of alternative colors may also utilize photosynthesis. The other colors might be preferred in places that receive a different mix of solar radiation than that received on Earth.

Plants on Earth are green because they contain chlorophyll. The chlorophyll is green because it absorbs mainly blue and red light in order to produce food for the plant via photosynthesis, while reflecting the green light frequency.

Scientists at NASA point out that if the stars for other planets were in a different state than our sun and if the light frequency that reached the planets' surface was different, then the plants would have also evolved a different type of photosynthetic pigment (other than chlorophyll). This pigment would be dedicated towards the different light frequencies received by the planet. This would cause plants to appear a different color from green, such as red and yellow.

According to recent studies, no photosynthetic plants would be blue-colored. This is because blue light provides some of the highest photosynthetic yields in the light spectrum. It is important for blue light to be absorbed rather than reflected. This is based on the physical quality of different frequencies of light produced by known types of stars.

One terrestrial example of energy conversion based on something other than ordinary light involves radiotrophic fungi that convert high energy gamma rays into useful energy using the melanin. (In most organisms melanin is used to protect the organism against ultraviolet and solar radiation.) Even still, ordinarily fungi derive their energy from decomposing other biomass, rather than by converting radiation into energy for itself.

It could even be possible for photosynthesis to occur using infrared light. In such an environment, plants may actually appear black.

It is fascinating to image the variations of life that are possible, even if life is based on the same fundamentals as our own.

Reference: Wikipedia article; Wikinews article; NASA - NASA Predicts Non-Green Plants on Other Planets; Dadachova, E; Bryan RA, Huang X, Moadel T, Schweitzer AD, et al. (2007). "Ionizing Radiation Changes the Electronic Properties of Melanin and Enhances the Growth of Melanized Fungi". PLoS ONE 2 (5): e457. doi:10.1371/journal.pone.0000457; Candace Lombardi "NASA: Plants on other planets not green". CNET, April 11, 2007; Julie Steenhuysen "New hue: Plants on other planets may be yellow, red". Reuters, April 11, 2007; Ker Than "Colorful Worlds: Plants on Other Planets Might Not Be Green". Space.com, April 11, 2007; “The Color of Plants on Other Worlds” by Nancy K. Kiang, Scientific American April 2008

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Related articles

• Video: What Would Trees Look Like On Other Planets?
• Predictions of Evolution of Alien Life
• Communicaion with Alien Civilizations
• Odds of Humaniods Evolving again
• Part 5: Blue Plants
• Part 4: Silicon Life
• Part 3: Arsenic Life
• Part 2: Exotic Amino Acids
• Part 1: Mirror Life

Possible types of Alien Lifeforms (Part 4: Silicon Life)

A popular Sci-Fi topic is alternative forms of life. A common idea is that life could be based on silicon instead of carbon.

The idea is based on the fact that silicon has valence number of four. This means that silicon atoms can be arranged in rings and in long chains that may be useful to create structures upon which biological molecules could be built. However, there are many drawbacks that must be overcome for life to efficiently use silicon as its basis.

Silicon based lifeforms would not have organic molecules used within Terran life. DNA would not be the basis for such life. However, the silicon based molecules may not be stable without an added level of complexity because silicon has a larger atomic radius and mass than carbon. It also has more difficulty forming stable molecules, particularly where water is present.

Even still, it is a possibility. For some reason, many Sci-Fi depictions show silicon based life as being rocklike in appearance. I'm not sure where this idea comes from. It's a bit like assuming carbon based lifeforms look like a lump of coal. I have a feeling that if we do discover silicon based lifeforms, they may resemble us more than many expect.

Reference: Wikipedia article and “Are Aliens Among Us?” by Paul Davies, Scientific American December 2007

Related articles

• Video: What Would Trees Look Like On Other Planets?
• Predictions of Evolution of Alien Life
• Communicaion with Alien Civilizations
• Odds of Humaniods Evolving again
• Part 5: Blue Plants
• Part 4: Silicon Life
• Part 3: Arsenic Life
• Part 2: Exotic Amino Acids
• Part 1: Mirror Life

Possible types of Alien Lifeforms (Part 3: Arsenic Life)

What if the basic molecules of life where completely different? Life on Earth needs water, carbon, nitrogen, hydrogen, oxygen, and phosphorous. This last one is of particular interest.

Phosphorous is not particularly abundant on Earth. Yet Terran life needs the element. A similar element that could replace phosphorous is arsenic. Of course, arsenic is poisonous to us. This is because it is so similar to phosphorous. It may be possible that life could have evolved on other worlds to use arsenic instead of phosphorous. This is because arsenic can do everything that phosphorous does (in the way of structural bonding and energy storage). It could also be used to drive metabolism. On such a world, phosphorous would be the poison because it would interfere with those functions, much as arsenic interferes with the functions of phosphorous in life on Earth.

Is it possible for lifeforms to be poisonous to each other because of their basic chemistry? Would it be dangerous for arsenic based lifeforms and phosphorous-based lifeforms to simply touch each other or even to life in the same space?

References: “Are Aliens Among Us?” by Paul Davies, Scientific American December 2007

Related articles

• Video: What Would Trees Look Like On Other Planets?
• Predictions of Evolution of Alien Life
• Communicaion with Alien Civilizations
• Odds of Humaniods Evolving again
• Part 5: Blue Plants
• Part 4: Silicon Life
• Part 3: Arsenic Life
• Part 2: Exotic Amino Acids
• Part 1: Mirror Life

The Drake Equation

Drake's Equation is an often quoted formula that is used to guesstimate the number of extraterrestrial civilizations that might be in existence at any one time. It combines eight (often arbitrary) elements from star formation to stages in life development. From this is derived a supposed number that represents how many advanced civilizations might exist in our galaxy right now.

These elements are:

• Average rate of star formation in our galaxy (R*)


• Fraction of those stars that have planets (f_p)


• Average number of planets that potentially support life per star that has planets (n_e)


• Fraction of those planets that actually develop life at some point (f_l)


• Fraction of those planets that then develops intelligent life (f_i)


• Fraction of those civilizations that develop technology that can and does send detectable signals of their existence into space (f_c)


• And, the length of time such civilizations remain detectable via their transmissions (L)

The formula this looks something like N = R* x f_p x n_e x f_l x f_i x f_c x L.

Here's an example of how to use the formula based on estimates of values for its variables.

• R* = 10/year (10 stars formed per year, on the average over the life of the galaxy)


• f_p = 0.5 (half of all stars formed will have planets)


• n_e = 2 (stars with planets will have 2 planets capable of supporting life)


• f_l = 1 (100% of these planets will develop life)


• f_i = 0.01 (1% of which will be intelligent life)


• f_c = 0.01 (1% of which will be able to communicate)


• L = 10,000 years (which will last 10,000 years)

Drake's values give N= 10 × 0.5 × 2 × 1 × 0.01 × 0.01 × 10,000 = 10 civilizations with which there is possibility for us to currently communicate. This can be useful to provide rough guests as to the chances of how successful we can expect to be in our hunt for E.T.'s with programs like SETI.  SETI has a lot of equipment pointed into space looking for signals.

However, the formula is so full of guests, it may not have any value at all. In fact, even the elements of the formula are themselves guests. For example, one might question why star formation rate has any impact on how many planets may form with life. Also, given more modern understandings of our galaxy, such as the Rare Earth Hypothesis, many other factors may be more important that those used the Drake Equation. Additionally, there is a problem that many stars have been discovered to have Hot Jupiters, which would destroy any terrestrial worlds, thus preventing the opportunity for life to develop in that star system. Even worse, the question is raised about our own arrogance in the assumption that all life would resemble us enough to communicate in the same forms as we do.

It appears now that the Drake Equation is actually pseudo-science. It is not based on any hypothesis. It is nothing more than a series of guests. It does not produce anything that is testable. In fact, it's author, Dr. Frank Drake, didn't originally intend for this formula to be used in the way that is has been. It was meant to be an organizational tool for the discussion about intelligent life in the Universe specifically for a gathering called The Green Bank Meeting in 1960, so named for its location at the Green Bank Telescope.

Right now, it seems the best way to know how common life is in our galaxy is to explore it. The Drake Equation is more of a mathematical toy than an actual useful formula.

Possible type of Alien Lifeforms (Part 2: Exotic Amino Acids)

For the most part, life on Earth uses the same set of nucleotides (amino acids) to form the basis of their DNA. In all, almost all known life uses 20 particular amino acids. These are often classified by their bases as A (adenine), C (cytosine), G (guanine) and T (thymine). These are the basic building blocks of DNA. They are also used to build proteins. Of course, from a certain point of view, DNA is just a really long protein.

How DNA uses these amino acids is described by Paul Davies in his article Are Aliens among Us? published in Scientific American, Dec 2007. He states, "The genetic code is based on triplets of nucleotides, with different triplets spelling out the names of different amino acids. The sequence of triples in a gene dictates the sequence of amino acids that must be strung together to build a particular protein."

Alien lifeforms may use exotic amino acids that are far different than the ones used by life on Earth. It is possible that the set of amino acids we use may not even appear on other worlds. Evidence by scientific study suggests that there are many other forms of amino acids that may be useful (or at least available) for other types of life. Evidence of exotic amino acids on other worlds has come from meteorites. Also, others have been synthesized in the lab.

Other lifeforms from other worlds may be completely different from us while still using the same basic DNA structure we use. A question remains, would life formed by exotic amino acids be all that much different than Terran life in appearance? Would the exotic amino acids lead life to evolve along completely different paths that we as yet have not conceived?

Reference: “Are Aliens Among Us?” by Paul Davies, Scientific American December 2007

Related articles

• Video: What Would Trees Look Like On Other Planets?
• Predictions of Evolution of Alien Life
• Communicaion with Alien Civilizations
• Odds of Humaniods Evolving again
• Part 5: Blue Plants
• Part 4: Silicon Life
• Part 3: Arsenic Life
• Part 2: Exotic Amino Acids
• Part 1: Mirror Life

Possible types of Alien Lifeforms (Part 1: Mirror Life)

On Earth, life uses what is called right-handed DNA. Right-handed DNA uses left-handed amino acids, sometimes described as homochiral. The fact that all lifeforms on Earth use Right-handed DNA suggests that all life here is descendant from a common group of ancestors.

Why does the difference matter? If single cell members of mirror life (with left-handed DNA) are placed in a nutrient broth consisting of only left-handed amino acids, the lifeforms will not be able to thrive. The same is true of the reverse.

Mirror life is a type of lifeform that uses the same type of DNA structure, but where the DNA is left-handed. This type of life, in turn, used right-handed amino acids.

The possibly that life on other worlds may be mirror life is very exciting. If found, it would lend tremendous evidence that life is possible in other forms as well.

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Reference: "Are Aliens Among Us?" by Paul Davies, Scientific American December 2007

Related articles

• Video: What Would Trees Look Like On Other Planets?
• Predictions of Evolution of Alien Life
• Communicaion with Alien Civilizations
• Odds of Humaniods Evolving again
• Part 5: Blue Plants
• Part 4: Silicon Life
• Part 3: Arsenic Life
• Part 2: Exotic Amino Acids
• Part 1: Mirror Life

Identification of years

How many people actually know that there is no year zero on the common Western (Gregorian) calendar. This creates logical problems that are hard to deal with in the lay population. Most people assume an understanding and use of zero. I would even catch myself thinking in terms of having a year zero had I not known a little more about our calendar than the average bear. Bottom line, on our calendar, the year 1 BC is followed by 1 AD.

Just as there is no year zero, there is not zero century. Our 21st Century is 2001 to 2100. The last year of the 21st Century is 2100, not the first year. That's fairly counter-intuitive. This does force me to think when I talk about periods in the 16th through 19th Centuries. It is very easy to think that 18th Century is the same as the 1800's.

So, there is no year zero, no matter how confusing that ends up being. Until we choose another calendar system, this will be a contentious issue.

Another point to discuss is how to identify years. The most common method for years counting backward is B.C., and A.D. for our current era (years that count forward). These two abbreviations refer a previously accepted date for the birth of Jesus Christ. It is now commonly agreed that if Jesus Christ did exist, his birth was more likely between the period of 8 and 4B.C. This means the start year of our calendar is pretty arbitrary, as it is not associated with any particular event. Yet, we still use terms that directly reference Jesus' birth. Alternative terms that have been proposed are BCE (Before our Common Era) and CE (our Common Era). This turns the arbitrary date away from being Christian centric, but in a way, it still attempts to enforce that old world calendar on others. I see BCE/CE used more frequently these days, but I do not believe it will ever become the norm.

To accept the arbitrary nature of our calendar and to establish some Information Age standard, those Europeans have come up with a supposed standard ISO-8601. This document is meant to be an international standard, but isn't really in common use. The problem with ISO-8601 is that is renumbers the years that count backwards. 1BC becomes 0000 and 2BC becomes -0001. Unless every history book ever written is updated to this new attempt to renumber the years, I doubt ISO-8601 will ever be in common use by anyone other than software programmers.

The Earth is Flat and the Heaven supported above us?

There is a misconception that the bible states the world is a sphere.  There is no evidence for this misconception.  However, some interpret Isiah 40:22 to mean the bible says the Earth is a sphere, but that scripture does not say this.  In fact, that scripture makes other false statements about the nature of our world and the Universe.

From the King James Version:

"It is he that sitteth upon the circle of the earth, and the inhabitants thereof are as grasshoppers; that stretcheth out the heavens as a curtain, and spreadeth them out as a tent to dwell in:"

First, a circle is not a sphere.  Second, it makes reference to the heavens as being a curtain stretched over the Earth as a tent.  This is actually in line with the beliefs at the time.  The surface of the Earth was viewed as flat, and the heavens were assumed to be stretched out over it, like a bowl turned over being placed on top a support, or like a tent covering. Many scriptures refer to the heavens in this manner. Check out Genesis 1:8, 2:4, 11:4, 28:12, just for starters.

In fact, some translations of the first creation account in Genesis 1:8 describes god as calling into existence the firmament of the heaven.  A firmament is a support or pillar.  To extend the simile of Isiah 40:22, it is the tent pole upon which heaven is held up above the Earth.  This is intended as literal, not poetic.  This was the literal belief about the nature of heaven used throughout the Bible's Old Testament.  It is a holdover from Egyptian mythology which stated that a large mountain was arisen from the sea to support the heaven.^[1]

To further the bowl reference, this word firmament is an interesting derivative.  In the Hebrew, the word used for firmament is raqiya which means an extended solid surface or flat expanse.  Raqiya is derived from the Hebrew word raqa, which means beaten out or to spread material by beating, hammering, or stamping.  This is a reference to the process of making a metal bowl by hammering metal flat.  Thus in Job 37:18 we read about Elihu asking Job "Can you beat out [raqa] the vault of the skies, as he does, hard as a mirror of cast metal." (From the Kings James Version: "Hast thou with him spread out the sky which is strong, and as a molten looking-glass?")  Additionally, Job 22:14 makes reference to the "vault of heaven", sometimes translated as "vault of the sky" or "arch of heaven" in the context of discussing where god resides.^{[2][3][4][4 backup link]}

To get back to the idea of the Earth being flat, many scriptures make references to the Earth being built upon a foundation. Note Job 38:4, Zechariah 12:1, Hebrews 1:10, Revelations 13:8 and Revelations 17:8.  The Earth is also described as being fixed in place in scriptures such as 1 Chronicles 16:30.

All of these promote the idea that the ancients had false concepts about the nature of Earth being flat and heaven being placed over the Earth and supported somehow so that is does not fall.  It shows that the writers of the bible showed an acceptance and believed in these false concepts.

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Though not used as a resource for this article, I also recommend reading The Three-Story Universe (backup link).

Medical Myths and the Myths about those myths - Part 6 (woman decides the sex of her baby)

An old myth is that the woman decides the sex of her baby when she gets pregnant. Even today, some cultures still have this belief. So, what's the myth about this myth? When I was a child, I learned that it is the father that determines the sex of the baby. Of course, this is as big of a myth as believing the mother has control over this event.

The fact of the matter is that barring actual (and expensive) medical intervention, and for all practical purposes, the selection of a baby's sex is completely random. Neither the mother nor the father can make the selection through conscientious efforts.^[1] There are many different and often bizarre myths surrounding conception, as an article at babycenter.com covers.^[2]

Many different actions can be tried with to improve the chance of getting pregnant, but sex selection is still not directly in the hands of either parent. Granted, Y (male) sperm have been deemed weaker and can be more affected by a woman's pH balance more so than X (female) sperm, but more boys are born than girls on a world wide basis. Nature has already figured all this out for us, and if decision making has happened, it is a result of our species' evolution, and not preferences we conjure up in our own minds.