PLEASE, READ THIS SCIENTIFIC AMERICAN'S ARTICLE:
NASA has released a series of photographs of Mars (November 17, 2000), in which we observe many gullies that seem to have been carved by water. Mars Global Surveyor spacecraft, currently orbiting Mars, captured those images of channels inside of Hale crater. NASA says that those images give support to NASA's discoveries released last June.
In a report published in Science (Michael C. Malin, Kenneth S. Edgett, Evidence for Recent Groundwater and Surface Runoff on Mars, Science, Volume 288, Number 5475 Issue of 30 Jun 2000, pp. 2330-2335), scientists assured that some ditches observed on Mars surface are water surplus flowing out from underground.
The presence of water is not evidence in favor of the existence of life in any place of the universe. Water is the main factor that contributed for the origin of living beings and the subsequent support of life on the Earth, but it is not the solitary factor involved in the creation of protobionts. Protobionts appeared by the confluence of many essential factors in a specific position and time in the course of the global evolution of the Universe. We could find water, organic compounds and enough energy at a given place, but not to find a single form of life.
Mars, as NASA says, is an unfriendly planet for life. The current climatic conditions on Mars cannot support any form of life. The species inhabiting our planet are so sensitive to environmental changes that many living beings on Earth are threatened by extinction due to the present changes of the climate of the Earth. If life is in danger on a planet that is hospitable for living beings, how they can survive on a world plenty of adverse conditions like Mars? Let’s see the surroundings of Mars:
Mars is a planet with scarce water, it has not a protective ozone layer, its gravity is weaker than Earth's gravity and practically it has not a magnetic field. Besides, life was not generated in a 10 ml test tube with water to top. The synthesis of a single protobiont and many organic molecules needed huge amounts of water. In case that a protobiont had been emerged on Mars, how would it be maintained alive with those so small quantities of water? If all water vapor in Martian atmosphere were condensed, it would make a pond smaller than a hundredth of one centimeter deep. Yes, we have to look under the surface of Mars.
If a living form would have existed on Mars, it is not there today. Our hope on finding traces of ancient life on Mars have dropped to almost zero given that the scientists have concluded -by the analysis of Martian meteorites- that Mars has been an icy planet for almost four billion years. The propitious moment for the emergence of biosystems in our Solar System happened about 3.5 billion years ago, when Mars already was a frosty planet.
If the meteorite ALH84001 originally had prokaryotes, they could be formed by the same elements of the microhabitat of the supposed bacteria: What is it the composition of the meteorite found in the Antarctic? Has it traces of organic compounds, as it could be expected? We thought that the meteorite had microfossils; nonetheless, carful analysis showed that there were inorganic in origin.
In Newton Crater photo, some channels seem to be streams made by great masses of thin sand moving downhill dragged by winds, not by water (C. S. Bristow, S. D. Bailey and N. Lancaster, The Sedimentary Structure of Linear Sand Dunes. Nature, 406, 56 - 59. July 6, 2000).
This could be applied to the other photos. The alcoves seem to be depressions caused by sinking of the land, or by landslides. So that the water runs in big quantities (enough to erode the soil at the degree observed in Mars) it was necessary that large volumes of water flowed from a spring. But we have not observed springs on Mars. It was said that the multiplicity of channels at one area would suggest that water would be very abundant, but scientists have not been observed a pale drop of water, neither a spring, or a water cloud, or a pond or deposit of water down the supposed currents. We only see sand and rocks.
NASA's scientists consider that if our Earth supports life, as a consequence any place in the universe can support it. In almost all TV interviews, some people assure that if we have found a bacterium that is resistant under terrestrial extreme conditions, we will be able to find them at any place of the universe. Is it scientific reasoning? Let us examine the details of this stuff:
We have found extremophiles living on Earth's environments. Earth is a planet with all the propitious conditions to originate protobionts, which could have been the ancestors of the extremophiles. Earth supports a wide variety of living beings (biodiversity). However, we are considering terrestrial organisms living in Earth's conditions. The fact that the extremophiles are able to subsist on earth at present time means that they have evolved from previous ancient organisms.
Whether the terrestrial organisms have come from space, or have appeared on the Earth, the terrestrial extremophiles adapted to environments where terrestrial life is possible.
We cannot obtain universal conclusions from specific premises when those arguments apply to a specific place and time. Not all phenomena which are true on a known time and/or place would be valid for other unknown eras and/or other places.
However, the possibility of finding biological systems on other planets of cosmic bodies is difficult because the conditions given on Earth have been essential to preserve a bimolecular organization; consequently, the conditions in other planets would have to be similar to Earth's conditions, not precisely in reference to minuscule details, but into the span of possibilities for life which are present on the Earth. We know that living beings on Earth emerged as a result of various factors that have continued being favorable for the subsistence and evolution of biosystems.
Unquestionably, we cannot discharge the hypothesis that there could be life on Mars because we have not explored in deep the planet and life is possible everywhere in the Universe, as long as the conditions are propitious to life.
ABOUT SAND STORMS ON MARS
As I have said in a previous paragraph, most of the streams attributed to water erosion-action seem to be channels excavated by sliding of sand. The proofs that we have on this event are the pictures of two massive seasonal sand storms obtained by Space Telescope Hubble on June 26, 2001. We have seen those sand storms very near to the Martian northern Pole, where water is present. This is important because we have seen other photos of Mars that show some geological features that look as sedimentary layers.
Martian winds tow great quantities of dry sand (very light) through more than one half long the face of the planet. When sand passes over polar zones and through frosty water ice clouds, it becomes heavier, and winds place it over ground as wet layers, one over another. Through time, warm and dry winds desiccate the sand layer; deposit other layers of loose sand on the wet sand layer and, eventually, it will place more humid sand upon the dry layers until take shape of stratums, as if they were layers of sediments. This mechanism could have occurred more frequently during the geological past of Mars, when the planet was hotter and there were water vapor clouds.
In their report of February 19, 2003, NASA's scientists explained the origin of the basins on Mars. According to data gathered by the 2001 Mars Odyssey spacecraft, the answer for the origin of Mars channels is snow that unfreezes, not the action of fresh rain, large "torrents of water", or underground water springs (please, continue reading "Sediment Layers" below).
EARTH AND MARS: SIMILAR PLANETS?
1. Earth has a great Moon that controls the spinning movement of the planet and stabilizes the terrestrial axis of rotation in relation with its orbital plane. It permits that the climate be stable on Earth and that not drastic changes occur from one day to another. Conversely, Mars has two small satellites that do not interfere a great deal with its rotary motion. Thus, the Martian climate is highly unstable and inconsistent, doing impossible the continued existence of organisms. By the way, NASA discovered that Mars a global warming is taking place on Mars.
2. The mass of waters on Mars is very low, while on Earth, the mass of water occupies more than three quarters of Earth's surface. There are clouds on Earth, which is a signal of great amounts of water; there are copious rains, there are vigorous rivers and lakes. We cannot see those accidents on Mars because if all water vapor in the Martian atmosphere were condensed, it would make a pond smaller than a hundredth centimeter deep. Besides, the oceans on Mars would be two inches deep puddles of sulfurous water acidified by the spontaneous reaction between the sulfur dioxide and water.
3. Earth has glacial; Mars has also frozen Polar Regions. Earth poles are massive, and its poles are interrelating with oceans, instead, glacial on Mars are barely layers of ice. The Martian north polar cap, composed primarily of water ice, is 1200 km across and up to 3 km thick in a few places. The water volume on Mars is about 4% of the south polar ice mass on Earth. If Mars is running a warming, then that ice can melt to form water currents and lakes.
4. Earth has an ozone layer. Mars has not protection against cosmic radiation.
5. Mars' gravity is 2.63852 lesser than Earth's (Earth's = 1).
6. Earth's superficial temperatures average 17°C. In comparison, Mars' superficial temperatures average 55 degrees below zero.
7. Earth's atmosphere abounds in Nitrogen (76%) and Oxygen (21%). In contrast, Mars' atmosphere abounds in carbon dioxide (an adverse saturation of 95.3 %).
8. The atmospheric pressure on Mars is adversely low. Thus, in not many places, where the pressure is most favorable, liquid water is restricted to limits from 0 °C to 10 °C. This means that fresh water on Mars starts to boil at 10 °C. In contrast, we can find water on Earth in all three physical states (liquid, solid and gaseous) between 0 and 100 °C.
9. As for the soil, the largest difference is the composition. Soil on Earth is rich in humus (decomposing organic material), minerals that are bonded to soil particles, as potassium, magnesium and calcium, and minerals bonded to other substances like nitrates, phosphates and sulphates. Of course, there are bacteria on Earth that can fractionate the sulphur from complex compounds. In contrast, Mars' soil is unusually rich in Sulphur originated by atmospheric chemical processes. (James Farquhar, et al., Evidence of Atmospheric Sulphur in the Martian Regolith from Sulphur Isotopes in Meteorites; Nature, Vol. 404, No. 6773, pp. 50 - 52, issue of 2 March 2000). Unfortunately, Mars lacks of such bacteria.
10. A strong geomagnetic field shields our planet from the irradiance of plasma during the solar electromagnetic storms. Mars' magnetic field is very weak (one half of the Earth's magnetic field), therefore, it would not protect living beings similar to those on the Earth.
SEDIMENT LAYERS ON MARS
NASA released a series of images of Martian surface. In their comments, the scientists of NASA explain that the smoothness of the layers and the sharpness of some walls are clues in favor of the presence of large masses of water in Mars in ancient times. Immediately after those photos were released, other scientists advanced eves when they assured that this discovery was evidence in favor of the existence of life on mars. The Media distorted the reports saying that NASA had discovered life on Mars. We cannot assure something like such reports from the Newspapers (please read: http://science.nasa.gov/headlines/)
Many Newspapers that published the work of NASA scientists wrote, "If there is water, there is life", when they must say "If there is water, there COULD be living beings..." The presence of water is not a reliable proof on the existence of life anywhere. There are doubts about the real nature of those sediment stratums, in case that effectively the water were sculpted those layers, we should test first the quality of water.
There are ponds of water on Earth, which are inert by containing oxidative sulfurs and other substances that impede the synthesis of complex organic molecules. Of course, this inhibits the emergence of living beings in all forms, depending on the concentration of sulfurs. As we wrote above, sulfurs are present in Mars, so in its atmosphere as in its soil. It could not be possible if in the geological past of Mars it had not had a higher concentration of sulfurs than the current one. The composition of present Martian soil is rich in iron oxides and reactive oxidizing agents that give support to the last assertion. We knew beforehand that the emergence of living beings on Mars was not possible because its environmental conditions were highly aggressive for living beings, more hostile in the ancient times of Mars than at present.
We have to verify that it was water what shaped the gullies, not the sand; then, we can assure that large masses of water flowed long ago on the surface of Mars. In case that we verify that it was water what shaped those creeks, we should verify that the water was clean and suitable as to maintain living organisms. Optimistically, the finding of traces of water on Mars increases the probabilities of the occurrence of living beings in the Martian distant past. If we consider the present conditions of Mars, interpolating them in its geological context we could conclude that Mars has never supported living organisms, but we cannot assure this because we have not explored the planet in deep.
We have said in the above paragraphs (Life on Mars) that most of the streams attributed to water erosion-action seem to be made by sand erosion. Last proofs we have on it are the pictures of two massive seasonal sand storms obtained by Space Telescope Hubble on June 26, 2001. We have seen those sand storms very near to Martian northern Pole, where water is present. This is important because we have seen other photos showing sedimentary layers on Mars.
Somebody can say that those images are evidence of lost lakes and oceans on Mars, but if we adhere to truth, we have other explanations:
- Martian winds tow great quantities of dry sand (very light) through more than half long the face of the planet. When sand passes over polar zones and through frosty water ice clouds, it becomes heavier, and winds place it over ground as wet layers, one over another. Through time, warm and dry winds desiccate the sand layer; deposit other layers of loose sand on the wet sand layer and, eventually, it will place more humid sand upon the dry layers until take shape of stratums, as if they were layers of sediments. This mechanism could have occurred more frequently during the geological past of Mars, when the planet was hotter and water vapor clouds existed.
- The photo of West Candor Chasma is really impresive. At first glance you could associate the strata with wet sedimentary layers. But, if you observe more carefully, you will see that it seems to be solidified lava layers, which flew when it was melted, accumulated forming strata over strata, and solidified as it got colder.
However, our hypothesis of sand flowing quickly over downhill has been taken into account. Shinbrot et al. have demonstrated by models the plausibility of our model with positive results. They found that sand is more plausible than water to have carved gullies on the waterless surface of Mars (Shinbrot, T., Duong, N. H., Kwan, L. and Alvarez, M. M. Proceedings of the National Academy of Sciences USA, published online, doi:10.1073/pnas.0308251101, 2004).
Furthermore, McSween, H. Y. et al. have given us credit about the lava hypothesis for most of chasms on Mars. They said that magma may have provided the water that etched gullies on Mars' surface (McSween, H. Y. et al. Geochemical evidence for magmatic water within Mars from pyroxenes in the Shergotty meteorite. Nature 409, 487 - 490 (2001), but we still hold our hypothesis: it was only magma. Read another proof supporting our hypothesis in NASA's site Click here.
After a long wait, geologists are providing us with realistic assessments on support of what we had reported some years ago, when we talked about the origin of most of the gullies and sediment layers on Mars.
Many people accept as a true, unsupplied with a coherent scrutiny, that living beings exist on Mars. Those people take each slight discovery as an evidence of life without a single proof.
The methodical reasoning is not built on speculations, but on observation of natural facts.
By the findings made on Martian soil by the Viking Landers, many scientists took the reactions of the organic material, detected by the analyzers of the Mars Viking Landers in 1976, as an irrefutable corroboration of the existence of life on the red planet.
The composition of Martian soil is such that it impedes the successful beginning and the preservation of organisms in and on it. The last has to be added to the high bombardment of the Cosmic Rays.
According to the experiments performed by A. S. Yen et al., the high quantity of inorganic super-oxides and peroxides in Mars' soil provokes the decomposing of the organic molecules (Science, Vol. 289, No. 5486, pp, 1909-1911, issue of September 15, 2000), inhibiting the biological and/or the chemical synthesis and stability of organic compounds in the recognized stratum between the surface and 10 cm under floor (limit of the Viking's drill).
On the other hand, as I have indicated in the previous paragraphs, the compounds in the atmosphere of Mars are aggressive for living beings. No matter which form of life we put under scrutiny.
I'd like to hear, some day before I die, that we have found life on other planets. It would be something prominent for contemporary Biology on supporting my theory about the origin of life. However, as a biologist, I consider that we should try to discover life forms farther than Mars; we should seek in other worlds, where the physicochemical conditions could be more propitious for life, for instance, one of the moons of Jupiter.
I know our limitations of current space technology, but I also know that when NASA, ESA and the Japan Space Agency want it, they can achieve it. I think that in the nearby or far future, we will be capable to find life beyond Earth, but I do not agree on assuring things without solid scientific evidence.
IS THERE LIFE ON MARS?
June 05, 2004
We do not know. Apparently, Mars is an inert planet at present -hostile to any known living form. Current Mars' conditions would not permit the survival of any known living system. The nucleic acids, which are the basis of inheritance, would be immediately destroyed by the highly oxidative substances found in the Martian atmosphere and soil. Those substances would impede the synthesis of organic molecules essential for life. However, microorganisms can have adapted to these Martian conditions.
However, there could be traces of primitive life on the red planet, such as fossils of archeobionts or chemical traces of metabolic activity from organisms more or less evolved than archeobionts.
IT IS NOT THAT WE REMAIN INFLEXIBLE ON THE FIXED IDEA OF DENYING THE EXISTENCE OF LIVING BEINGS OUT FROM EARTH. WE WOULD LIKE TO KNOW POSITIVELY THAT THERE IS LIFE ON ANY WORLD OF OUR SOLAR SYSTEM. BUT WE DO NOT AGREE ON TRANSFORM THE “IT COULD BE" BY THE "IT INDEED IS" WITHOUT FACTS THAT SUPPORT ANY SCIENTIFIC RESEARCH, OR WITHOUT EXAMINING THE DATA WITH SCIENTIFIC PRECISION. NASA AND ESA PROVIDES US WITH TRUSTWORTHY DATA ON THEIR FINDINGS, BUT WE, THE SCIENTIFIC COMMUNITY OUT FROM NASA AND ESA, ARE OBLIGED TO AVOID THE MISCONCEPTIONS OF THE REPORTS BY THE WHIM OF THE MEDIA. WE ARE SCIENTISTS; WE DO NOT OBTAIN ANY PROFIT FROM OUR WORK.
The possibilities of finding living beings outside the Earth (specifically on Mars) are pretty low, but the possibilities of detecting traces of the past existence of protobionts on it and indications of the development of protobionts in the Solar Nebula are high.
Perhaps, other missions will discover at least some residues of primitive life on Mars. Possibly, the living beings were abundant on Mars many years ago in a five centimeters depth sea, the deepest ocean that possibly had existed on Mars.