War in Ukraine A quick word on Conspiracies: (Thanks to threeworldwars.com) There are three ways of exposing a Conspiracy: 1. One is for any of the participants in the conspiracy to break...
Tag: sufficient (page 1 of 3)
Growing up as a child I was fascinated by the master magicians and their amazing feats of prestidigitation and the incredible skill necessary to fool the eyes with conjure, coin or card. I performed my own magic shows in my basement for friends and fam...
A Failed War On Cancer Sayer Ji, Green Med InfoEver since Richard Nixon officially declared a war on cancer in 1971 through the signing of the National Cancer Act, over a hundred billion dollars of taxpayer money has been spent on research and drug development in an attempt to eradicate the disease, with trillions more spent by the cancer patients themselves, but with disappointing results.Even after four decades of waging full-scale “conventional” (s [...]
Dr. Ben Kim, GuestGood overall health begins with a healthy gut. Chronic illness begins with breakdown in the gut.This is where I typically start with clients looking to address any health challenge.If you’re looking for lasting improvement in any area of your health, it’s best not to think of your body parts as being independent compartments. Every cell communicates with every other cell, not always directly, but via the fluids, hormones, and neurotransmitters that trave [...]
 |
| An Indiana firm is developing a method to make oxygen on Mars for Nasa. Bacteria and algae will use Martian soil as fuel to pump out oxygen. Mars could be scattered with biodomes containing the organisms. And future astronauts could use this oxygen to survive on the surface (artist's illustration shown) |
- An Indiana firm is developing a method to make oxygen on Mars for Nasa
- Bacteria and algae will use Martian soil as fuel to pump out oxygen
- Mars could be scattered with biodomes containing the organisms
- And future astronauts could use this oxygen to survive on the surface
If humans land on Mars in the 2030s as planned, one thing that will be essential to their survival will be self-sufficiency, as they won’t be able to take too much cargo with them.
With this in mind Nasa is testing whether oxygen can be created from Martian soil, without having to carry it all the way from Earth.
The innovative method would see bacteria or algae use the soil as fuel, pumping out usable oxygen in the process for astronauts on the surface.
Nasa has been working with Techshot Inc of Greenville, Indiana to develop this method in a so-called ‘Mars room’, which mimics the conditions on the red planet.
It is able to simulate the atmospheric pressure on the planet, in addition to the day-night temperature changes and the solar radiation that hits the surface.
In experiments, certain organisms were capable of producing oxygen from Martian soil - known as regolith - and they also removed nitrogen from it.
‘This is a possible way to support a human mission to Mars, producing oxygen without having to send heavy gas canisters,’ said Eugene Boland, chief scientist at Techshot.
‘Let’s send microbes and let them do the heavy-lifting for us.’
The research is part of the Nasa Innovative Advanced Concepts (NIAC) Programme.
It’s envisioned that biodomes could be scattered across the surface to produce the oxygen needed for humans to survive.
The oxygen produced could also be stored for later use.
But while experiments on Earth are all well and good, the scientists want to test their method actually on Mars in the near future.
+3
The 'Mars room', shown, is able to simulate the atmospheric pressure on the planet, in addition to the day-night temperature changes and the solar radiation that hits the surface. In experiments certain organisms were capable of producing oxygen from Martian soil inside the laboratory
When humans land on Mars in the future (artist's illustration of the landing shown left), they will need to be as self-sufficient as possible.
To do so, an upcoming rover - such as the 2020 Mars rover - could carry small container-like devices with Earth organisms inside.
The containers would be buried a few inches underground in certain locations, to see how successful they are at producing oxygen.
Sensors inside the container would detect how much oxygen was made, and report the findings back to a satellite in Mars orbit.
The scientists note that the container would be sealed tightly, to prevent the organisms being exposed to - and possibly contaminating - the Martian surface.
But if proven successful, future explorers on Mars may use multiple biodomes like this to produce the oxygen they need to survive.
 |
| CGI of how the Milky Way galaxy may appear from deep space |
Excerpt from thespacereporter.com
Analysis of data collected by NASA’s Kepler space telescope has led researchers at the Australian National University and the Niels Bohr Institute to conclude that Earth is only one of billions of potentially life-sustaining planets in our galaxy.
In order for a planet to sustain life, it must orbit its star at just the right distance to provide sufficient light and warmth to maintain liquid water without too much radiation. This perfect orbital distance is considered to be the habitable zone.
According to a Weather Channel report, there are an average of two planets per star in the Milky Way Galaxy orbiting within their habitable zones. That brings the total number of planets with the potential for holding liquid water to 100 billion.
Scientists assume that water would be an essential ingredient for life to evolve on other planets, but it is not a certainty.
“If you have liquid water, then you should have better conditions for life, we think,” said Steffen Jacobsen of Niels Bohr. “Of course, we don’t know this yet. We can’t say for certain.”
To reach their conclusion, the researchers studied 151 planetary systems and focused on those with four or more planets. They used a concept called the Titus-Bode law to calculate where unseen planets might be located in a system based on the placements of other planets around the star. The Titus-Bode law suggested the existence of Uranus before it was actually seen.
The data will require further analysis and the sky will require further searching to yield a more accurate number of potentially life-harboring planets.
“Some of these planets are so small the Kepler team will probably have missed them in the first attempt because the signals we get are so weak. They may be hidden in the noise,” Jacobsen said.
The initial analysis, however, is extremely promising in the possibility of finding habitable planets. “Our research indicates that there are a lot of planets in the habitable zone and we know there are a lot of stars like the one we’re looking at. We know that means we’re going to have many billions of planets in the habitable zone,” said Jacobsen, who considers that “very good news for the search for life.”
Excerpt from thespacereporter.com
Astronomers are baffled by images of plumes rising from Mars’ atmosphere in images taken by amateur astronomers in March and April 2012.
The plumes were present for about 10 days though their shapes and sizes changed rapidly during that time, from finger-like tendrils to spherical blobs.
Researchers have proposed several possible explanations for the plumes, which are discussed in an article just published in the journal Nature.
Each of the theories being considered poses problems. One theory, for instaqnce, proposes the plumes are caused by the same magnetic influence that causes the aurora borealis, or Northern Lights, on Earth. The movement of electrically charged particles from the Sun, driven by the solar wind towards Earth’s poles, results in these particles colliding with molecules of gas. These collisions produce the strange lights known as aurorae.
In the study, the researchers admit, “Mars aurorae have been observed near where the plume occurs, a region with a large anomaly in the crustal magnetic field that can drive the precipitation of solar wind particles into the atmosphere.”
They move on to consider another option, namely that the plumes might be clouds high in the Martian atmosphere.
A highly reflective cloud of either water ice, carbon dioxide ice, or dust particles could explain the plumes. But according to computer models, the presence of these clouds “would require exceptional deviations from standard atmospheric circulation models to explain cloud formations at such high altitudes,” explained the paper’s lead author, Agustin Sanchez-Lavega of the Universidad del Pais Vasco in Spain.
The plumes were seen approximately 120 miles (200 km) from Mars’ surface, which is problematic because the highest Martian clouds are seen is 60 miles (100 km) above the planet’s surface. The only way water can condense so far up is if the temperature in that part of Mars’ atmosphere drops 370 degrees Fahrenheit, or 50 degrees Kelvin, below its norm.
Condensation of carbon dioxide would require twice this temperature drop.
A third theory posits the flumes are caused by atmospheric dust. A wind powerful enough to transport dust 111 miles (180 km) above Mars’ surface could occur only around noon, when the Sun’s heat would be strong enough to create such wind currents.
However, the plumes were seen not at noon but in the mornings along the terminator that separates the planet’s day and night sides.
Recently, data from the Hubble Space Telescope was found showing the plumes back in 1997.
 |
| Planck has mapped the delicate polarisation of the CMB across the entire sky |
Excerpt from bbc.com
Scientists working on Europe's Planck satellite say the first stars lit up the Universe later than previously thought.
Earlier observations of this radiation had suggested the first generation of stars were bursting into life by about 420 million years after the Big Bang.
Planck's data indicates this great ignition was well established by some 560 million years after it all began.
"This difference of 140 million years might not seem that significant in the context of the 13.8-billion-year history of the cosmos, but proportionately it's actually a very big change in our understanding of how certain key events progressed at the earliest epochs," said Prof George Efstathiou, one of the leaders of the Planck Science Collaboration.
Subtle signal
The assessment is based on studies of the "afterglow" of the Big Bang, the ancient light called the Cosmic Microwave Background (CMB), which still washes over the Earth today.
Prof George Efstathiou: "We don't need more complicated explanations"
It contains a wealth of information about early conditions in the Universe, and can even be used to work out its age, shape and do an inventory of its contents.
Scientists can also probe it for very subtle "distortions" that tell them about any interactions the CMB has had on its way to us.
Forging elements
One of these would have been imprinted when the infant cosmos underwent a major environmental change known as re-ionisation.
Prof Richard McMahon: "The two sides of the bridge now join"
These hot giants would have burnt brilliant but brief lives, producing the very first heavy elements. But they would also have "fried" the neutral gas around them - ripping electrons off the hydrogen protons.
And it is the passage of the CMB through this maze of electrons and protons that would have resulted in it picking up a subtle polarisation.
Impression: The first stars would have been unwieldy behemoths that burnt brief but brilliant lives The Planck team has now analysed this polarisation in fine detail and determined it to have been generated at 560 million years after the Big Bang.
The American satellite WMAP, which operated in the 2000s, made the previous best estimate for the peak of re-ionisation at 420 million years.
The problem with that number was that it sat at odds with Hubble Space Telescope observations of the early Universe.
Hubble could not find stars and galaxies in sufficient numbers to deliver the scale of environmental change at the time when WMAP suggested it was occurring.
Planck's new timing "effectively solves the conflict," commented Prof Richard McMahon from Cambridge University, UK.
"We had two groups of astronomers who were basically working on different sides of the problem. The Planck people came at it from the Big Bang side, while those of us who work on galaxies came at it from the 'now side'.
"It's like a bridge being built over a river. The two sides do now join where previously we had a gap," he told BBC News.
That gap had prompted scientists to invoke complicated scenarios to initiate re-ionisation, including the possibility that there might have been an even earlier population of giant stars or energetic black holes. Such solutions are no longer needed.
No-one knows the exact timing of the very first individual stars. All Planck does is tell us when large numbers of these stars had gathered into galaxies of sufficient strength to alter the cosmic environment.
By definition, this puts the ignition of the "founding stars" well before 560 million years after the Big Bang. Quite how far back in time, though, is uncertain. Perhaps, it was as early as 200 million years. It will be the job of the next generation of observatories like Hubble's successor, the James Webb Space Telescope, to try to find the answer.
Being built now: The James Webb telescope will conduct a survey of the first galaxies and their stars
- Planck's CMB studies indicate the Big Bang was 13.8bn years ago
- The CMB itself can be thought of as the 'afterglow' of the Big Bang
- It spreads across the cosmos some 380,000 years after the Big Bang
- This is when the conditions cool to make neutral hydrogen atoms
- The period before the first stars is often called the 'Dark Ages'
- When the first stars ignite, they 'fry' the neutral gas around them
- These giants also forge the first heavy elements in big explosions
- 'First Light', or 'Cosmic Renaissance', is a key epoch in history
The new Planck result is contained in a raft of new papers just posted on the Esa website.
These papers accompany the latest data release from the satellite that can now be used by the wider scientific community, not just collaboration members.
Dr Andrew Jaffe: "The simplest models for inflation are ruled out"
It was hoped that Planck might find direct evidence in the CMB's polarisation for inflation - the super-rapid expansion of space thought to have occurred just fractions of a second after the Big Bang. This has not been possible. But all the Planck data - temperature and polarisation information - is consistent with that theory, and the precision measurements mean new, tighter constraints have been put on the likely scale of the inflation signal, which other experiments continue to chase.
What is clear from the Planck investigation is that the simplest models for how the super-rapid expansion might have worked are probably no longer tenable, suggesting some exotic physics will eventually be needed to explain it.
"We're now being pushed into a parameter space we didn't expect to be in," said collaboration scientist Dr Andrew Jaffe from Imperial College, UK. "That's OK. We like interesting physics; that's why we're physicists, so there's no problem with that. It's just we had this naïve expectation that the simplest answer would be right, and sometimes it just isn't."
Excerpt from dailymail.co.ukBy Jonathan O'Callaghan UK researchers studied the asteroid impact 66 million years agoThey found the heat near the impact site in Mexico was not intense enough to ignite plant materialA heat pulse lasted less than a minute...
There is nothing better than a bit of mythbusting (which accounts for the popularity of the television program of the same name), so here we are again, presenting you with a new list of terribly common misconceptions and myths – this time about science.
10
Evolutionary Improvements
The Myth: Evolution causes something to go from “lower” to “higher”
While it is a fact that natural selection weeds out unhealthy genes from the gene pool, there are many cases where an imperfect organism has survived. Some examples of this are fungi, sharks, crayfish, and mosses – these have all remained essentially the same over a great period of time. These organisms are all sufficiently adapted to their environment to survive without improvement.
Other taxa have changed a lot, but not necessarily for the better. Some creatures have had their environments changed and their adaptations may not be as well suited to their new situation. Fitness is linked to their environment, not to progress.
9
Humans Pop In Space
The Myth: When exposed to the vacuum of space, the human body pops
This myth is the result of science fiction movies which use it to add excitement or drama to the plot. In fact, a human can survive for 15 – 30 seconds in outer space as long as they breathe out before the exposure (this prevents the lungs from bursting and sending air into the bloodstream). After 15 or so seconds, the lack of oxygen causes unconsciousness which eventually leads to death by asphyxiation.
8
Brightest Star
The Myth: Polaris is the brightest star in the northern hemisphere night sky
Sirius is actually brighter with a magnitude of ?1.47 compared to Polaris’ 1.97 (the lower the number the brighter the star). The importance of Polaris is that its position in the sky marks North – and for that reason it is also called the “North Star”. Polaris is the brightest star in the constellation Ursa Minor and, interestingly, is only the current North Star as pole stars change over time because stars exhibit a slow continuous drift with respect to the Earth’s axis.
7
Five Second Rule
The Myth: Food that drops on the floor is safe to eat if you pick it up within five seconds
This is utter bunkum which should be obvious to most readers. If there are germs on the floor and the food lands on them, they will immediately stick to the food. Having said that, eating germs and dirt is not always a bad thing as it helps us to develop a robust immune system. I prefer to have a “how-tasty-is-it” rule: if it is something really tasty, it can sit there for ten minutes for all I care – I will still eat it.
6
Dark side of the Moon
The Myth: There is a dark side of the moon
Actually – every part of the moon is illuminated at sometime by the sun. This misconception has come about because there is a side of the moon which is never visible to the earth. This is due to tidal locking; this is due to the fact that Earth’s gravitational pull on the moon is so immense that it can only show one face to us. Wikipedia puts it rather smartly thus: “Tidal locking occurs when the gravitational gradient makes one side of an astronomical body always face another; for example, one side of the Earth’s Moon always faces the Earth. A tidally locked body takes just as long to rotate around its own axis as it does to revolve around its partner. This synchronous rotation causes one hemisphere constantly to face the partner body.”
5
Brain Cells
The Myth: Brain cells can’t regenerate – if you kill a brain cell, it is never replaced
The reason for this myth being so common is that it was believed and taught by the science community for a very long time. But in 1998, scientists at the Sweden and the Salk Institute in La Jolla, California discovered that brain cells in mature humans can regenerate. It had previously been long believed that complex brains would be severely disrupted by new cell growth, but the study found that the memory and learning center of the brain can create new cells – giving hope for an eventual cure for illnesses like Alzheimer’s.
4
Pennies from Heaven
The Myth: A penny dropped from a very high building can kill a pedestrian below
This myth is so common it has even become a bit of a cliche in movies. The idea is that if you drop a penny from the top of a tall building (such as the Empire State Building) – it will pick up enough speed to kill a person if it lands on them on the ground. But the fact is, the aerodynamics of a penny are not sufficient to make it dangerous. What would happen in reality is that the person who gets hit would feel a sting – but they would certainly survive the impact.
3
Friction Heat
The Myth: Meteors are heated by friction when entering the atmosphere
When a meteoroid enters the atmosphere of the earth (becoming a meteor), it is actually the speed compressing the air in front of the object that causes it to heat up. It is the pressure on the air that generates a heat intense enough to make the rock so hot that is glows brilliantly for our viewing pleasure (if we are lucky enough to be looking in the sky at the right time). We should also dispel the myth about meteors being hot when they hit the earth – becoming meteorites. Meteorites are almost always cold when they hit – and in fact they are often found covered in frost. This is because they are so cold from their journey through space that the entry heat is not sufficient to do more than burn off the outer layers.
2
Lightning
The Myth: Lightning never strikes the same place twice
Next time you see lightning strike and you consider running to the spot to protect yourself from the next bolt, remember this item! Lightning does strike the same place twice – in fact it is very common. Lightning obviously favors certain areas such as high trees or buildings. In a large field, the tallest object is likely to be struck multiple times until the lightning moves sufficiently far away to find a new target. The Empire State Building gets struck around 25 times a year.
1
Gravity in Space
The Myth: There is no gravity in space
In fact, there is gravity in space – a lot of it. The reason that astronauts appear to be weightless because they are orbiting the earth. They are falling towards the earth but moving sufficiently sideways to miss it. So they are basically always falling but never landing. Gravity exists in virtually all areas of space. When a shuttle reaches orbit height (around 250 miles above the earth), gravity is reduced by only 10%.
Inspired by an excellent LiveScience Article. This article is licensed under the GFDL because it contains quotations from Wikipedia.
Excerpt from Ad Astra
by Robert Zubrin
Mars Is The New World
Among extraterrestrial bodies in our solar system, Mars is singular in that it possesses all the raw materials required to support not only life, but a new branch of human civilization. This uniqueness is illustrated most clearly if we contrast Mars with the Earth's Moon, the most frequently cited alternative location for extraterrestrial human colonization.In contrast to the Moon, Mars is rich in carbon, nitrogen, hydrogen and oxygen, all in biologically readily accessible forms such as carbon dioxide gas, nitrogen gas, and water ice and permafrost. Carbon, nitrogen, and hydrogen are only present on the Moon in parts per million quantities, much like gold in seawater. Oxygen is abundant on the Moon, but only in tightly bound oxides such as silicon dioxide (SiO2), ferrous oxide (Fe2O3), magnesium oxide (MgO), and aluminum oxide (Al2O3), which require very high energy processes to reduce.
The Moon is also deficient in about half the metals of interest to industrial society (copper, for example), as well as many other elements of interest such as sulfur and phosphorus. Mars has every required element in abundance. Moreover, on Mars, as on Earth, hydrologic and volcanic processes have occurred that are likely to have consolidated various elements into local concentrations of high-grade mineral ore. Indeed, the geologic history of Mars has been compared to that of Africa, with very optimistic inferences as to its mineral wealth implied as a corollary. In contrast, the Moon has had virtually no history of water or volcanic action, with the result that it is basically composed of trash rocks with very little differentiation into ores that represent useful concentrations of anything interesting.
You can generate power on either the Moon or Mars with solar panels, and here the advantages of the Moon's clearer skies and closer proximity to the Sun than Mars roughly balances the disadvantage of large energy storage requirements created by the Moon's 28-day light-dark cycle. But if you wish to manufacture solar panels, so as to create a self-expanding power base, Mars holds an enormous advantage, as only Mars possesses the large supplies of carbon and hydrogen needed to produce the pure silicon required for producing photovoltaic panels and other electronics. In addition, Mars has the potential for wind-generated power while the Moon clearly does not. But both solar and wind offer relatively modest power potential — tens or at most hundreds of kilowatts here or there. To create a vibrant civilization you need a richer power base, and this Mars has both in the short and medium term in the form of its geothermal power resources, which offer potential for large numbers of locally created electricity generating stations in the 10 MW (10,000 kilowatt) class. In the long-term, Mars will enjoy a power-rich economy based upon exploitation of its large domestic resources of deuterium fuel for fusion reactors. Deuterium is five times more common on Mars than it is on Earth, and tens of thousands of times more common on Mars than on the Moon.
But the biggest problem with the Moon, as with all other airless planetary bodies and proposed artificial free-space colonies, is that sunlight is not available in a form useful for growing crops. A single acre of plants on Earth requires four megawatts of sunlight power, a square kilometer needs 1,000 MW. The entire world put together does not produce enough electrical power to illuminate the farms of the state of Rhode Island, that agricultural giant. Growing crops with electrically generated light is just economically hopeless. But you can't use natural sunlight on the Moon or any other airless body in space unless you put walls on the greenhouse thick enough to shield out solar flares, a requirement that enormously increases the expense of creating cropland. Even if you did that, it wouldn't do you any good on the Moon, because plants won't grow in a light/dark cycle lasting 28 days.
But on Mars there is an atmosphere thick enough to protect crops grown on the surface from solar flare. Therefore, thin-walled inflatable plastic greenhouses protected by unpressurized UV-resistant hard-plastic shield domes can be used to rapidly create cropland on the surface. Even without the problems of solar flares and month-long diurnal cycle, such simple greenhouses would be impractical on the Moon as they would create unbearably high temperatures. On Mars, in contrast, the strong greenhouse effect created by such domes would be precisely what is necessary to produce a temperate climate inside. Such domes up to 50 meters in diameter are light enough to be transported from Earth initially, and later on they can be manufactured on Mars out of indigenous materials. Because all the resources to make plastics exist on Mars, networks of such 50- to 100-meter domes could be rapidly manufactured and deployed, opening up large areas of the surface to both shirtsleeve human habitation and agriculture. That's just the beginning, because it will eventually be possible for humans to substantially thicken Mars' atmosphere by forcing the regolith to outgas its contents through a deliberate program of artificially induced global warming. Once that has been accomplished, the habitation domes could be virtually any size, as they would not have to sustain a pressure differential between their interior and exterior. In fact, once that has been done, it will be possible to raise specially bred crops outside the domes.
The point to be made is that unlike colonists on any known extraterrestrial body, Martian colonists will be able to live on the surface, not in tunnels, and move about freely and grow crops in the light of day. Mars is a place where humans can live and multiply to large numbers, supporting themselves with products of every description made out of indigenous materials. Mars is thus a place where an actual civilization, not just a mining or scientific outpost, can be developed. And significantly for interplanetary commerce, Mars and Earth are the only two locations in the solar system where humans will be able to grow crops for export.
Interplanetary Commerce
Mars is the best target for colonization in the solar system because it has by far the greatest potential for self-sufficiency. Nevertheless, even with optimistic extrapolation of robotic manufacturing techniques, Mars will not have the division of labor required to make it fully self-sufficient until its population numbers in the millions. Thus, for decades and perhaps longer, it will be necessary, and forever desirable, for Mars to be able to import specialized manufactured goods from Earth. These goods can be fairly limited in mass, as only small portions (by weight) of even very high-tech goods are actually complex. Nevertheless, these smaller sophisticated items will have to be paid for, and the high costs of Earth-launch and interplanetary transport will greatly increase their price. What can Mars possibly export back to Earth in return?It is this question that has caused many to incorrectly deem Mars colonization intractable, or at least inferior in prospect to the Moon.
For example, much has been made of the fact that the Moon has indigenous supplies of helium-3, an isotope not found on Earth and which could be of considerable value as a fuel for second generation thermonuclear fusion reactors. Mars has no known helium-3 resources. On the other hand, because of its complex geologic history, Mars may have concentrated mineral ores, with much greater concentrations of precious metal ores readily available than is currently the case on Earth — because the terrestrial ores have been heavily scavenged by humans for the past 5,000 years. If concentrated supplies of metals of equal or greater value than silver (such as germanium, hafnium, lanthanum, cerium, rhenium, samarium, gallium, gadolinium, gold, palladium, iridium, rubidium, platinum, rhodium, europium, and a host of others) were available on Mars, they could potentially be transported back to Earth for a substantial profit. Reusable Mars-surface based single-stage-to-orbit vehicles would haul cargoes to Mars orbit for transportation to Earth via either cheap expendable chemical stages manufactured on Mars or reusable cycling solar or magnetic sail-powered interplanetary spacecraft. The existence of such Martian precious metal ores, however, is still hypothetical.
But there is one commercial resource that is known to exist ubiquitously on Mars in large amount — deuterium. Deuterium, the heavy isotope of hydrogen, occurs as 166 out of every million hydrogen atoms on Earth, but comprises 833 out of every million hydrogen atoms on Mars. Deuterium is the key fuel not only for both first and second generation fusion reactors, but it is also an essential material needed by the nuclear power industry today. Even with cheap power, deuterium is very expensive; its current market value on Earth is about $10,000 per kilogram, roughly fifty times as valuable as silver or 70% as valuable as gold. This is in today's pre-fusion economy. Once fusion reactors go into widespread use deuterium prices will increase. All the in-situ chemical processes required to produce the fuel, oxygen, and plastics necessary to run a Mars settlement require water electrolysis as an intermediate step. As a by product of these operations, millions, perhaps billions, of dollars worth of deuterium will be produced.
Ideas may be another possible export for Martian colonists. Just as the labor shortage prevalent in colonial and nineteenth century America drove the creation of "Yankee ingenuity's" flood of inventions, so the conditions of extreme labor shortage combined with a technological culture that shuns impractical legislative constraints against innovation will tend to drive Martian ingenuity to produce wave after wave of invention in energy production, automation and robotics, biotechnology, and other areas. These inventions, licensed on Earth, could finance Mars even as they revolutionize and advance terrestrial living standards as forcefully as nineteenth century American invention changed Europe and ultimately the rest of the world as well.
Inventions produced as a matter of necessity by a practical intellectual culture stressed by frontier conditions can make Mars rich, but invention and direct export to Earth are not the only ways that Martians will be able to make a fortune. The other route is via trade to the asteroid belt, the band of small, mineral-rich bodies lying between the orbits of Mars and Jupiter. There are about 5,000 asteroids known today, of which about 98% are in the "Main Belt" lying between Mars and Jupiter, with an average distance from the Sun of about 2.7 astronomical units, or AU. (The Earth is 1.0 AU from the Sun.) Of the remaining two percent known as the near-Earth asteroids, about 90% orbit closer to Mars than to the Earth. Collectively, these asteroids represent an enormous stockpile of mineral wealth in the form of platinum group and other valuable metals.
Historical Analogies
The primary analogy I wish to draw is that Mars is to the new age of exploration as North America was to the last. The Earth's Moon, close to the metropolitan planet but impoverished in resources, compares to Greenland. Other destinations, such as the Main Belt asteroids, may be rich in potential future exports to Earth but lack the preconditions for the creation of a fully developed indigenous society; these compare to the West Indies. Only Mars has the full set of resources required to develop a native civilization, and only Mars is a viable target for true colonization. Like America in its relationship to Britain and the West Indies, Mars has a positional advantage that will allow it to participate in a useful way to support extractive activities on behalf of Earth in the asteroid belt and elsewhere.But despite the shortsighted calculations of eighteenth-century European statesmen and financiers, the true value of America never was as a logistical support base for West Indies sugar and spice trade, inland fur trade, or as a potential market for manufactured goods. The true value of America was as the future home for a new branch of human civilization, one that as a combined result of its humanistic antecedents and its frontier conditions was able to develop into the most powerful engine for human progress and economic growth the world had ever seen. The wealth of America was in fact that she could support people, and that the right kind of people chose to go to her. People create wealth. People are wealth and power. Every feature of Frontier American life that acted to create a practical can-do culture of innovating people will apply to Mars a hundred-fold.
Mars is a harsher place than any on Earth. But provided one can survive the regimen, it is the toughest schools that are the best. The Martians shall do well.
Robert Zubrin is former Chairman of the National Space Society, President of the Mars Society, and author of The Case For Mars: The Plan to Settle the Red Planet and Why We Must.
 |
| The 10-meter South Pole Telescope and the BICEP (Background Imaging of Cosmic Extragalactic Polarization) Telescope at Amundsen-Scott South Pole Station, which detected evidence of gravitational waves, is seen against the night sky with the Milky Way in this National Science Foundation picture taken in August 2008. |
By Ben P. Stein, Inside Science
Harvard researchers rocked the science community last March with an apparent discovery of gravitational ripples that gave credence to cosmic inflation theory – a finding that met as much skepticism as enthusiasm. Now, further analysis raises more doubts.
"Extraordinary claims require extraordinary evidence." This phrase, popularized by the late Carl Sagan, kept going through my head on March 17, the day that researchers involved with BICEP2, a telescope in Antarctica, made a big announcement at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
The researchers reported that BICEP2 detected gravitational waves from the first moments after the big bang, a feat, which if confirmed, would open up a new field of study and would surely be recognized in a future Nobel Prize.
Gravitational waves are ripples in space and time. They're created when any object with mass accelerates. However, they're extremely weak, making them very hard to detect directly. Even for the most massive and cataclysmic events, such as the collision of two black holes, their effects, observed from Earth, are very hard to detect.
If you're looking for a detectable gravitational wave signal, what bigger event can there be than cosmic inflation? According to inflation theory, the universe multiplied its size by as much as 10 trillion trillion trillion times in the first fractions of a second after the big bang. Inflation would have generated lots of gravitational waves. In turn, gravitational waves can subtly change the properties of light that they pass through. Specifically, they can slightly affect the polarization of light, the direction in which light's electric fields vibrate. The universe's rapid expansion during inflation would have amplified the waves' imprint on the early light in the universe.
The state-of-the-art BICEP2 experiment, which uses super-sensitive superconducting sensors, could detect tiny changes in polarization in the cosmic microwave background, the very first light released in the universe, which is still reaching us today. The BICEP2 researchers reported a very high polarization signal, known as B-mode polarization after its characteristics, in the cosmic microwave background, which they interpreted as a strong gravitational wave signal in the early universe.
Detecting this polarization signal was a striking result, announced in a series of scientific talks and a press conference shortly after a preprint of the paper was posted online. Notice these last two points: announced at a press conference, and a preprint posted online. A preprint is a written paper that has not been formally reviewed by independent peers or published in a scientific journal.
Nonetheless, scientists and reporters alike reported excitement over the results. If true, they would provide the greatest experimental support yet of cosmic inflation, and the first direct detection of gravitational waves. Previously, gravitational waves have been detected indirectly, such as in observations of pairs of stars falling towards each other: they were losing energy in the form of gravitational waves.
On the day of the BICEP2 announcement, and for many days afterward, people were largely accepting the results as correct and already jumping to the implications of the BICEP2 results for what appeared to be a new era of gravitational-wave cosmology.
In writing my story for Inside Science News Service, I was fortunate to get an early voice of skepticism from David Spergel, a theoretical cosmologist at Princeton University in New Jersey. He commented:
"Given the importance of this result, my starting point is to be skeptical. Most importantly, there are several independent experimental groups that will test this result in the next year."
Spergel explained that the new gravitational wave measurements did not appear to agree with those of previous experiments, known as WMAP and Planck, unless the simplest models of inflation were replaced by more complicated ones. On the first day and week of coverage, I became very disappointed with the many commentators who disregarded or underemphasized that the earlier measurements from instruments on WMAP and Planck, which had been reported and covered for years.
Sure enough, in the weeks that followed, other researchers pointed out that the signal that BICEP2 detected may have been attributable to the polarization of light caused by dust in our galaxy. The BICEP2 team certainly knew that dust could also polarize light in a similar way to gravitational waves, but they used a model, based on the data that was available from the Planck satellite, that, the other researchers pointed out, may have underestimated the amount of dust in the part of the sky they were studying.
The BICEP2 paper underwent peer review and was published in Physical Review Letters. As a result of the peer-review process, the researchers made revisions, including removing the model that contained the lower estimates of dust based on the earlier Planck data, and thereby reducing the certainty with which they could state that they accounted for signals from interstellar dust.
During the summer, the BICEP2 and Planck collaborations agreed to work together to analyze their data, to help determine if gravitational waves had really been detected.
This week, the Planck team issued a preprint, based on an analysis of much additional data, showing a comprehensive map of dust in the sky. According to their analysis, the signal in the part of sky that BICEP2 analyzed could be completely attributable to dust and not to gravitational waves.
But, the story is not over. For starters, keep in mind the new preprint, like all newly posted publications, still needs to undergo formal peer review.
And the latest data do not completely rule out the possibility that the BICEP2 group detected a gravitational wave signal. If the evidence holds up at all, it would likely be a weaker signal, after accounting for the dust. Or, the gravitational-wave signal may completely turn to dust.
It may be possible to detect primordial gravitational waves in a different, less dusty part of the sky, or with new measurements by BICEP2, Planck or the many other experiments that are looking for them. Just as the first reported detections of exoplanets turned out to be false, perhaps this is a prelude to an actual detection of gravitational waves.
"You cannot ignore dust," he quotes from Planck scientist Charles Lawrence of NASA’s Jet Propulsion Laboratory in Pasadena, California.
The biggest lesson, to me, is that no one should rush to make announcements and pronouncements, whether big or small, even in the face of intense competition and the alluring prospects of launching a new field of study and winning a Nobel Prize.
Scientists, and the rest of the public, should follow the time-tested scientific practice of subjecting claims to sufficient levels of scrutiny, and waiting for other groups to validate results, before making bold statements. At the very least, there have been major caveats and qualifiers in announcing new data with potentially huge implications.
This work is licensed under a Creative Commons Attribution 4.0
International License.
unless otherwise marked.
Terms of Use | Privacy Policy
— Up ↑ —
Comments