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Can there be life on Mars?
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Can there be life on Mars? Dr Steven Cutts examines the pros and cons of an age-old topic that may be answered once and for all by new probes of the mysterious Red Planet. That idea was knocked on the head in 1965 when the Mariner spacecraft probe resolved the markings as chains of craters. But nourished by the imaginative creations of novelists, movie-makers, sci-fi writers and comic-book cartoonists, conjecture about the possibility of some kind of present or previous life on Mars has thrived for generations and is as yet unstemmed. Yet if there is life on Mars, would we even recognise it? Most scientists assume that any life in space is going to resemble life on earth and be made of carbon. But why should it resemble life on our own planet? Aren’t we guilty of planetary chauvinism, as obtuse as early European explorers arriving in distant lands and scorning their inhabitants as uncivilised because they spoke in incomprehensible tongues? We cannot know; for now we can only assume that the laws of physics and chemistry are the same throughout the universe. So what is there about our own environment on earth that may have helped Mars to create life? When we look for life on Mars it seems logical to assume that the planet needs liquid water and plenty of carbon-based chemistry. It also has to be reasonably but not overly warm. Excessive heat will destroy even the staunchest organic chemicals but where liquid water existed only at very low temperatures any life would struggle to survive. So where does that leave the rest of our solar system? Venus has an atmosphere that is simply far too hot for any complex chemicals to remain intact for long. Mars has an extremely thin atmosphere and one of its warm days would be on a par with the temperature at our polar regions. Life forms certainly exist in Antarctica but they evolved slowly in the comfortable nursery of the equatorial earth. Starting from scratch in a polar climate would seem to be unrealistic. It has been suggested that Jupiter might have an atmosphere that could support some sort of alien life, and this huge planet, 318 times the size of our own, certainly has a reasonable temperature at some altitudes and enough lightning to whip up some interesting chemistry. The problem with Jupiter is that it doesn’t have a solid surface; it is one vast atmosphere, so turbulent that even if life did form at a benign altitude, its fledgling organisms would soon be swept up into the freezing stratosphere or down to the superheated core. Nothing could survive such a transition. All the odds are, in my purely personal opinion, against any life being found on Mars. The robots that probe it have been sent not to discover life but to prove it’s not there. At least not yet. All human beings are covered in micro-organisms and if and when travellers from earth ever set foot on the Red Planet, the bugs they take with them will be shed on Martian soil, burrow into it and maybe survive for a while. In the 1960s NASA landed robotic probes on the moon. One of these was found by the crew of Apollo 14 in February 1971 who salvaged the camera from it and took that back to earth. It soon became apparent that the probe had taken terrestrial bacteria to the moon where those had survived for several years. Some species had died and none of them flourished but the mere fact that micro-organisms from earth had lived at all in the lunar environment was an eye-opener. Mars is a far more hospitable environment than the moon. The extremes of temperature are much less severe, the soil is more inviting and there’ may well be traces of frozen water. Some day there might well be life on Mars; but human life probably.
— AF |
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Trends Exposure soon after birth, or even before, to combustion gases and particularly engine exhaust, is strongly linked to the development of childhood cancers like leukemia, according to a report from the UK. “These results confirm the relative proximities of child cancer births to substance-specific hotspots from oil-based emissions, and to industrial sites known to discharge such materials,” Dr E.G. Knox, from the University of Birmingham, reports in the Journal of Epidemiology and Community Health. In the study, Dr Knox linked emission hotspots for specific chemicals, from maps available on the Internet to the birth addresses of children who later died from leukemia or other cancers before their 16th birthday.
— Reuters
Sun was always on Our sun was already shining brightly more than 4.5 billion years ago, as dust and gas was swirling into what would become the planets of the solar system, US researchers have
reported. They say their finding is the first conclusive evidence that the so-called protosun affected the developing solar system by emitting enough ultraviolet energy to catalyse the formation of organic compounds, water and other elements necessary for the evolution of life on Earth. “The basic question was, ‘Was the sun on or was it off?’” said Mark Thiemens of the University of California San Diego, who led the study. “There is nothing in the geological record before 4.55 billion years ago that could answer this.” So Thiemens and colleagues studied chemical “fingerprints” preserved in primitive chondrite meteorites.
— Reuters
Alcoholism
in the genes Fruit flies carry a gene — aptly named ‘hangover’ — that appears to help them become tolerant to alcohol. Tolerance is thought to promote dependence, so if a similar gene is found in humans, it might lead to drugs to treat or prevent alcoholism. In the journal Nature, researchers report that only fruit flies that carry a functioning “hangover” gene develop a tolerance for alcohol. “If humans have a gene that has a function similar to that of ‘hangover,’ we could interfere with the function of such a gene,” thereby preventing people from developing addiction to, alcohol, study author Dr Ulrike Heberlein of the University of California at San Francisco told Reuters Health. However, the researcher cautioned that this is still just speculation. During the study, Heberlein and colleagues mutated genes in flies, then exposed them to alcohol. “When flies are exposed to ethanol more than once they develop tolerance — i.e., it takes higher alcohol levels to reach the same degree of intoxication,” Heberlein explained. The researchers measured how intoxicated flies become from alcohol using a device called an inebriometer.
— Reuters |
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This
Universe Our Sun along with all its planets revolves around the centre of the galaxy. What is the speed at which it moves? This speed is 220 km per second! At this speed it takes about a million years to go around once, because the galaxy is so large. Humanity has not been around even for one revolution! It is useful to know that the galaxy does not rotate like a hard disc. As a result the matter and stars in the galaxy take on a spiral shape. By analysing the differential rotation of the stars as a function of distance from the centre of the galaxy astronomers have concluded that besides the visible stars and clouds there must be a lot more matter that exerts a gravitational force on the matter in the galaxy. This is the so-called dark matter. We still do not know the identity of this matter! Do animals, birds and other species of living things believe in God and worship him. If so what is the form of this God? I am flattered that in your view a mere scientist like me could answer this question. If God controls every thing living or non-living why must that God be one of human conception? Are we the only species that has the capability of concept formation? That appears unreasonable because, in spite of our domination we are a small minority. Can we think of a God without any of us being around? Did God create us all or we, humans, created a God because we found Him essential? In essence all I am saying is that I do not know. I do not know whether anyone else does. Every computer has a definite speed. What is the speed of the computer sitting in our head, namely our brain? It is natural to surmise that our brain is a little bit like a computer. We are not sure that the analogy is perfect. First of all, let me say that the speed of our brain is orders of magnitude slower than that of a modern computer. But we have a very large number of processors that more than compensate for this slowness. One of the consequences is that we have “consciousness” that computers do not — we perhaps do not want computers that would be conscious and free. In the operating system of our brain we have room for values, love, pride, anger and frustration. These would be considered dangerous quirks in most computer systems. It is possible most of these human qualities are a result of immense parallelism. Parallelism certainly compensated for lack of speed, but it might have also made us human and somewhat unpredictable. If I was given a choice between extreme fastness and extreme parallelism I would still choose the latter. Not surprising, because I confess to being partial towards the way we have been designed.
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Is there or has there ever been life on Mars? The question that has exercised the minds of men for well over a century may before long be settled by the findings of robots descending on a planet which has been the subject of speculation and controversy ever since the Italian
astronomer Giovanni Schiaparelli described in 1877 what he called “channels” on its surface.
Because the Italian for channels — canali — was erroneously translated as canals the idea soon became widespread that they were waterways constructed by intelligent beings.