"For most living things on Earth, exposure to a few hundred G would be fatal. They have no chance of surviving Vern's cannonball, or being blasted into space by an asteroid impact. But some creatures are so primitive that they can tolerate even 10,000 G* NASA CEO ordered his employees to study biology
Our ancestors might still have been from Adimeans, maybe billions of years ago life developed on Mars. Tiny, primitive creatures that thrived deep within the rocks and were fed by water and chemicals that seeped through those rocks? This hypothesis is brought up for discussion by the website .SPACE.COM.
“Now, imagine a giant asteroid crashing into Mars. Billions of shards of Madimai rock are thrown into space by the force of the collision. Hardy marine organisms have hitched a ride on some of the ejected rocks. Many fragments entered orbit around the Sun, and after hundreds of thousands of years, some of them collided with the Earth. Some of these rocks, the largest ones, reached the surface.
Some creatures survived the journey, inhabited the earth and eventually evolved into the variety of life as we know it. This scenario may seem far-fetched, because if organic molecules could be formed on Mars, it is more likely to assume that they could also be formed and were formed on Earth, and they would not need to take a space ride to it, but according to the author, Michael Fine, some of the latest discoveries in several scientific fields show that there is any chance of such a scenario.
It's not every day that scientists discover a new possible life form. Dr. Phillipa Uwins works in microscopy and microanalysis research at the University of Queensland, Australia. Last year she was asked to analyze some rock samples from a depth of several kilometers below sea level where drilling work was being done off the coast of Western Australia. The temperature of the rocks was about 150 degrees Celsius and the pressure was 2,000 times greater than the pressure at sea level on Earth.
During the electron microscope tests, Youins discovered what she suspected were dormant tiny creatures 20 nanometers wide (a nanometer is a billionth of a billionth of a meter). She called them nanobes.
To Youins' surprise, the tiny creatures grew when the pressure was reduced to normal atmospheric pressure, and the cell wall survived the intense radiation and vacuum of the electron microscope. Ewins teamed up with two microbiologists to further investigate the nanoves.
A variety of chemical experiments indicated that these tiny creatures contained DNA. These findings call a challenge to the authority that a cell with a diameter of 20 nanometers is too small to contain the main component of life as we cherish it (and this is also the argument against those nano-fossils in the famous meteorite from Mars). At Queensland University Ollie was discovered, the living creature that can survive on a meteorite traveling between the planets.
The creatures don't need to be as small as the nanoves to survive in space-like conditions. Other examples of extremofossils (creatures that can survive in very hostile conditions) have been found by researchers inside nuclear reactors.
Rocks from Mars found their way to Earth. Remember the dramatic announcement of NASA scientists from 1996 when they claimed to have found possible fossil evidence of a life form in a meteorite from Mars. The debate about this has not yet ended and from time to time the pendulum changes its position for or against this hypothesis. The rock sprang from Mars, spent 16 million years in orbit around the Sun, and then
- 13 thousand years ago, it collided with the Earth and landed on the glaciers of Antarctica. In 1984, scientists who were searching for meteorites found it. Ten years later, researchers discovered that it originated in Mars. This was made possible by comparing its composition with the analysis of the vaporous atmosphere in 1977, but there is another continuation to the detective's story.
So far, about a dozen meteorites from Mars are known. In 1911 one of them landed in Egypt and killed a dog. It took eighty years to realize that the unfortunate dog was killed by a stone thrown from Mars. The expert on craters, Dr. J. Melosh from the University of Arizona, estimates that about half the ton of materials from Mars fall on Earth every year.
Melosh predicts that some of the red meteorites showed no signs of violent shock when they were launched into space from the Martian soil. This requires a reconsideration of the authority according to which any material thrown into space first undergoes a process of melting due to the great heat resulting from the shock waves accompanying the impact of the celestial object. Melosh is now working on a theory according to which the rocks near the surface could have taken off into space without suffering from shock heating." The effect is similar to that of bread crumbs thrown from a shaken picnic basket."
The meaning of the discovery is that living creatures hiding inside these ejected rocks can survive the explosion of the asteroid. But there are still enough dangers in the flight from Mars to Earth. Melosh studied these dangers but still remains the conclusion that some creatures managed to pass them safely.
In his classic book from 1865, "From the Earth to the Moon", the science fiction writer Jules Verne writes about a manned spaceship with a light from a giant cannon. Verne was aware of the scientific fallacy of the idea - the astronauts could be crushed by forces thousands of times stronger than the pull of gravity. Wren knew that a rocket that would take off more gently was the more correct way to take off into space, but his audience in those days preferred the story of the cannon.
"For most living things on Earth, exposure to a few hundred G would be fatal. They have no chance of surviving Vern's cannonball, or being blasted into space by an asteroid impact. But some creatures are so primitive that they can tolerate even 10,000 g. In the journal "Astronomy" of the Israeli Astronomical Society, which was published about two weeks ago, Roni Moalem, from the Weizmann Institute of Science and a member of the faculty of the Givatayim Observatory, concludes that even if life may have originated on Earth, the raw materials for its creation came from space. The Earth receives a continuous supply of organic materials from a space source every day. Even in the distant past the situation was similar, although the amount of additional organic matter could have been much greater. Asteroid and comet impacts are a good source of organic matter. In the early years, it is estimated that the atmospheric pressure was 10 times greater than today, and therefore the speed of many meteorites slowed down. After their impact on the ground, the rate of contribution of organic substances was about 1.3 percent of the initial mass of the impacting body. Interplanetary dust particles - up to a tenth of a millimeter in size and weighing up to ten grams - are the main cause of organic material contributions.
X-ray tests show that about ten percent of them are made of organic carbon. What is important about them is that they do not burn up in the atmosphere but sink into it slowly.
Another possibility for the formation of organic molecules is, according to research by Prof. Akiva Bar-Nun from Tel Aviv University, shock waves can create organic molecules. He tested shock waves created by high heat and proved that it was possible to create amino acids in high concentration in the atmosphere, which at the time consisted mainly of water, ammonia, methane and ethane. In any case, he concludes that extraterrestrial sources probably provided the same amount of energy to create life as terrestrial sources, and that the mechanism of production of organic molecules depends significantly on the type of atmosphere that prevailed at the time in question. An oxidizing atmosphere is a thousand times more suitable for the formation of life than a neutral atmosphere.
Spectroscopic discoveries reveal to us that substances such as carbon, nitrogen oxide, etc. are found everywhere in space. According to the currently accepted model, these materials are formed in the cores of stars and are partly blown into space after the "death" of the star in a super nova explosion. These basic materials can connect both in space itself, inside the nuclei of comets and anywhere where suitable pressure and energy conditions prevail, such as the Earth itself. This connection of molecules of the type in question creates the building blocks of living things.
The only question is where the life that gave birth to us was created remains open in any case Mars can also be a good source. In December, the Mars Fuller spacecraft will land on Nader and will also send a pair of tiny spacecraft to crash into the rocks and examine their composition at a depth of several meters. Perhaps a hint of the answer will be given in this operation.
And in the same matter. The head of the US space agency, Dan Goldin, ordered all NASA employees to take a basic course in biology. The reason: the importance NASA attaches to the research effort focused on the search for life beyond Earth. For this purpose, the space agency also established a new research institute - for astrobiology. However, at this institute it is not possible for the time being to investigate extraterrestrial life - because there are currently no examples of other life forms, if they exist at all, outside of our planet. In the meantime one can only imagine what such life forms might look like.
Researchers of extraterrestrial life believe that these are life forms that probably existed here in the past. Humans are only a very late addition to our planet's tree of life. Most of the early life forms on earth were single-celled, bacteria and the like. The first creatures existed with the help of hydrogen sulfide, which is poison to most creatures today.
It is believed that the life of the extraterrestrials can be much different from the ones we know. That's why all of us, and especially NASA employees for whom the search for extraterrestrial life is a primary task, need to know a little biology.
One of the most important findings of recent years is the discovery of very complex carbon-based molecules found in interstellar space. They are probably part of the interstellar dust, which disrupts astronomical observations but is an important link in the process of the formation of solar systems, planets near other stars, and may even serve as a component in the process of the appearance of life.
In the research currently being carried out in the USA, which was reported at a scientific conference on "bio-astronomy" that took place this summer in Hawaii, they point to the possibility that interstellar dust components helped the first steps in the appearance of life on Earth.
Luis Almedola, a researcher from NASA's Ames Research Center, presented at the conference, for the first time, ice in which carbon-containing compounds - such as were found in interstellar space - had been injected. This ice was exposed to ultraviolet radiation. The ice consisted of water along with methane gas, carbon monoxide and ammonia, and it was kept in a vacuum and at a temperature of ten degrees above absolute zero. The process of irradiating ice with ultraviolet light reproduces what happens to a comet - which is a block of dirty ice - that cruises for billions of years in space and is affected by the radiation of the sun and other stars, until it collides with a planet.
The first process that occurs in this ice is the formation of complicated organic compounds. The second process - which is the innovation in this research - is the discovery of the appearance of membranes around some of the compounds created. The membranes are similar to the cell walls of the single-celled organisms that are known today.
The ice experiments were tested at room temperature and found to be similar to the materials extracted from the Murchison meteorite. This meteorite contains a relatively large amount of organic matter, which originated in space.
The experiments of Dr. Almandola's team show the existence of some connection between the organic substances in the grains of intercubic dust, and compounds that might have helped the appearance of life and its prosperity on the primordial earth.
The issue was also explored in the beautiful "meteor shower" seen in Israel at the end of last week.
