How did life begin and evolve on Earth?

And has life evolved elsewhere in the Solar System too?
16 October 2012


NASA asks this big question: How did life begin and evolve on Earth, and has it evolved elsewhere in the Solar System... 

Surprisingly, NASA are not the first to ponder this issue: in fact the Ancient Greeks considered the question of life outside Earth over 2,000 years ago. And some Greek philosophers, like Democritus, concluded that life must exist beyond Earth.

Clearly, life must have evolved elsewhere in the Solar System. As I explain in my two books, Other Life Exists (PublishAmerica, 2010) and KNOWN (, 2011), statistics argues that microscopic life lives in Europa, Ganymede, Callisto, and Enceladus. I stress two critical points:

First, Earth and Jupiter are not entirely separate worlds. British astronomer Dr. David Darling, co-author with D. Schulze-Makuch of We Are Not Alone (OneWorld Publications, 2010),  explains that interplanetary transfer of materials through meteorites eliminates the "separate worlds" notion. And as I explain, all the planets and their moons come from the same planetary nebula. Further, space probes are bringing the planets together conceptually. Probes have studied every planet. Some of the probes may have even carried bacteria to other solar system bodies. Indeed, when Apollo 12 brought a camera back to Earth from the moon, scientists found bacteria that had survived for 2 and 1/2 years in space. The bacteria may have even multiplied in space, so the first "extraterrestrial life" may have already come to Earth. In any case, Earth and Jupiter are not truly separate worlds.

Material transfers between planets when an asteroid collides with one planet and sends debris into space. Over the course of a billion years, some of that debris finds its way to another planet. Meteorites from Mars found on Earth prove these interplanetary transfers.

Just as the concept of The Old World and The New World changed over the centuries, so too is the concept of Earth and Jupiter as separate worlds. At one time, The New World was unknown. In 1492, The New World was still weeks away by sea travel, and it was a vast, unexplored place. Nowadays, it takes a few hours to travel between Europe and America. The two "worlds" are now perceived as parts of the same world. The same perceptual change is occurring with Jupiter and Earth. Many probes have explored Jupiter, and both planets come from the same planetary nebula. The two planets are part of the same system.

I make a second critical point in my books. A lifeless Europa is incredulous. NASA's Galileo team proved that Europa must harbor a vast subsurface ocean. They proved that by observations of cracks in the surface ice, and by observations of Europa as it bulges during orbit around Jupiter. Finally, Dr. Margaret Kivelson of the Galileo team proved that electromagnetic fluctuations around Jupiter and Europa support the idea of an internal ocean in the latter. Ice doesn't conduct electricity, but saltwater does. Electricity conducts through Europa just as it would through saltwater. Europa's ocean is estimated to hold over twice the saltwater as all Earth's oceans. I have no example of a lifeless body of saltwater that big, so I cannot conclude that Europa is lifeless.

Earth has 122 seas. Of course, all contain saltwater. And all those seas harbor microbial life. By refuting the "separate worlds" notion, I can equate the initial conditions that microbial life finds in saltwater taken from either Europa or Earth. To a microbe, saltwater is saltwater. From the microbe's perspective, it's inconsequential whether the saltwater is in an Earth ocean or in Europa's ocean.

And the Cassini probe found saltwater ice beyond Earth that has comparable salinity to Earth's oceans. Cassini is studying Saturn's moon Enceladus, which actually spews plumes of salt ice into space. In a NASA Press Release dated March 27, 2012, Dr. Carolyn Porco stated, "Cassini has flown several times now through this spray and has tasted it. And we have found that aside from water and organic material, there is salt in the icy particles. The salinity is the same as that of Earth's oceans." Dr. Porco is the leader of the Imaging Science team for NASA's Cassini probe. Dr. Frank Postberg, also a member of the Cassini team, concludes that the salt ice particles must emanate from a large body of saltwater inside Enceladus.

By eliminating the "separate worlds" notion, I can formulate a meaningful statistic to accurately predict microbial life in Europa. As stated, Earth holds 122 seas, and each sea harbors microbial life. Europa's ocean is simply the 123rd large body of saltwater encountered. No meaningful reason exists to treat it differently than the first known 122 bodies of saltwater. Therefore, the odds in favor of microbial life in Europa are at least 122 out of 123, or 99.2%.

Statisticians typically formulate statistics to predict future phenomena. They formulate two theories and then test both. When one theory proves true at least 95% of the time, they accept that theory as valid and reject the other theory. For example, a statistician might consider the weather in Florida over the last 100 years. By way of example, he might find that only in one year did the temperature drop to 32 degrees Fahrenheit on June 1. Again, this is just a hypothetical. Applying standard statistical methods, the statistician could validly conclude that the temperature will not drop to 32 degrees in Florida on June 1 this year. In the statistical meaning of the term, he knows that the temperature will not drop to 32 degrees on June 1. That knowledge exists even prior to observation.

So too with knowledge of microbial life in Europa. I know that microbials live in 122 Earth seas. I know that Europa holds a vast subsurface ocean. I can equate the initial conditions for any given cubic foot of saltwater from either Earth or Europa. Europa's saltwater is simply the 123rd body of saltwater I've studied. Therefore, the probability of microbials in Europa is 99.2%. I accept the theory that such life lives in Europa since the probability is greater than 95%. I reject the theory of a lifeless Europa.

Critics my argue that salinity levels in Europa may be so great as to bar life. But Cassini recently observed that the salinity of Enceladus' ice is the same as Earth's oceans. So to date, no saltwater body beyond Earth has been proven to be saltier than Earth's oceans. I have no reason to believe that Europa's saltwater is significantly different than Earth's. Therefore, the statistic presented above holds.

Two discoveries bolster the conclusion. Scientists have found amino acids in comets and organics in Enceladus' ice.

The same argument for life in Europa applies to Ganymede, Callisto, and Enceladus. Ganymede and Callisto orbit Jupiter. Like Europa, all of these moons harbor oceans beneath surface ice. In the statistical meaning of the word, I know that microbials live in these oceans. Considered independently, each of these saltwater bodies simply represents the 123rd body of saltwater encountered. The probability in favor of life is above 99%.

I make no arguments as to how life developed in these waters. Nor do I speculate on the types of life that may exist. I simply conclude that microbials must live in the four bodies of saltwater that exist in these moons of Jupiter and Saturn. So I can answer NASA's question, "Has life evolved elsewhere in the Solar System?" Indeed it has.


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