4. Hawking's Alien Invaders Might Be Microorganisms, B.G. Sidharth, Ph.D. International Institute For Applicable Mathematics & Information Sciences B.M. Birla Science Centre Adarshnagar, Hyderabad, India

Professor Stephen Hawking’s latest much publicized views about the existence of aliens and the threat his imagined aliens pose to mankind are somewhat naïve though not absurd, as these are based on the probability that such events may happen, given that there are so many stars and planets. However, even if Hawking's were correct, the greatest danger may not be technically advanced aliens looking for world's to conquer, but the diseases and microoganisms which might journey with them. Findings in recent years support the view that life in the universe may be widespread, and most likely, much of that life probably consists of bacteria, archae, and the viruses typically associated with them. There are already tantalizing clues suggestive of past and even present life on Mars. Life may have also taken hold on Europa, Titan, and other moons and planets in this solar system (see Journal of Cosmology, Vol 5). The French satellite CoRoT has just discovered a planet, called CoRoT-9b far beyond the Solar System, 1500 light years away. What makes this finding dramatic is that this could well be the first temperate planet similar to the planets of our Solar System. The new planet has a size roughly that of Jupiter with an orbit similar to Mercury. Unlike the four hundred other suspected exo planets, is neither extremely hot nor extremely cold. Its surface temperature is estimated to be between minus 20 degrees and 160 degrees Celsius, similar to Mars. Extremeophiles could certainly live under these conditions.

Very recently too NASA’s Jet Propulsion Laboratory in Pasadena has discovered a planet well outside the Solar System which has traces of organic molecules, the building blocks of life. The planet HD209458b has yielded traces of water, methane and carbon dioxide as detected by the Hubble Space Telescope and the Spitzer Telescope. Similar findings have been determined for the planet HD189733b.

These particular findings do not prove that life itself would be widespread, because it would be very improbable for life to develop, even if all the ingredients were present. But in the light of relatively recent work by Joseph, Schild, Gibson, Wickramasinghe, Sharov (see Journal of Cosmology Volume 5, ), and others, all this would lead to the dramatic conclusion that life may be abundant and wide spread throughout the universe (Joseph and Schild 2010a,b).

For several decades it has been believed that life originated on the earth billions of years ago in soups of water and chemicals which interacted with energy from the Sun. This would make the formation of life an improbable event. However, a number of scientists, including the present author (Sidharth, 2009, Journal of Cosmology Vol 1, Vol 10.) have been arguing for a dual mode origin of life, that is key ingredients like amino acids, but not yet fully formed life had reached Earth from outer space and chemically interacted with other ingredients present to form life. As similar conditions could have taken place on other planets, this would mean that the formation and evolution of life may be far more probable than thought earlier, particularly on planets located in habitable zones.

For example, complex molecules have been discovered in interstellar space, for example, in the cool dust clouds of the Orion Nebula and in the constellation of Sagittarius. Observations with telescopes, spectroscopes, radio telescopes and even orbiting observatories have confirmed the presence of molecules like methyl cyanide, water vapour, formaldehyde, methyl alcohol and even the potable ethyl alcohol. Clearly there are several organic molecules in the cool dust clouds spread across outer space.

This apart the space crafts Giotto and Vega which flew by Comet Halley glimpsed carbon rich molecules while space based observations revealed the presence of Ethane and Methane in Comets Hyakutake and Hale Bopp. Space dust reveals organic carbon. Interestingly some thirty tons of such carbon is brought down to the earth each day by the interstellar dust. Meteorites have shown nucleo basis, ketones, quinines, carboxylic acids, amines and amides. In fact as many as eight of the twenty amino acids involved in life processes have been identified besides some sixty others. Recently, NASA announced that an analysis of data from its Stardust mission revealed, for the first time the presence of the amino acid glycine in an icy comet.

The all important amino acids in nature come as left handed molecules and also right handed molecules reminiscent of a right handed spiral conch shell and a left handed spiral conch. The amino acids produced in the laboratory show equal quantities of the left handed and right handed varieties. There are no interactions involving light in such molecules. However in life processes, the left handed molecules predominate over the right handed molecules. Interestingly in the amino acids found on meteorites, we have exactly this preponderance of left handed amino acid molecules! This is the crucial trigger, and with chemical self organization leads to animate processes like photosynthesis.

It appears that amino acids, quinons, amphibilic molecules and the like were transported to the earth by meteoritic dust or cometary fragments. These could well have kick started the first life processes on the earth. Very recently, Amino acids were again observed in comets.

This also means that life would be well spread out in the universe and is not unique to Earth. As on Earth, microorganisms are probably the most abundant form of life on other planets. As argued by Joseph and Schild (2010; Journal of Cosmology Vol 5), given a habitable planet within a habitable zone, and if these microorganisms have genomes consisting of DNA, then life may evolve in patterns similar to those on Earth. Alien life may have evolved beyond the stage of modern Earth-based humans billions of years ago. Given the nature of life on Earth is competition for resources, and as technically advanced civilizations typically conquer those less developed, then Hawking's concern about the dangers of alien contact, should be take seriously.

However, it is probably not technologically advanced aliens, but alien microorganisms which pose the greatest danger to life on Earth (Joseph and Wickramasinghe 2010). When Columbus was followed by the Spanish conquistadors, it was not advanced weaponry which destroyed the native civilizations, but disease. The Spanish soldiers and monks carried diseases the natives had never before encountered and they died in vast numbers. Therefore it could be argued that the greatest threat is not from alien conquistadors. It is exposure to alien microorganisms which might prove disastrous to the inhabitants of Earth.

Joseph R., and Schild, R. (2010b). Biological Cosmology and the Origins of Life in the Universe. Journal of Cosmology, 5, 1040-1090.

Joseph, R., and Wickramasinghe, C. (2010). Comets and contagion: Evolution and diseases from space. ournal of Cosmology, 7. In press.

Sidharth, B. G. (2009). In Defense of Abiogenesis, Journal of Cosmology, 2009, 1, 73-75