Excerpt from huffingtonpost.comAs a society, we don't talk much about emotions. Conversations tend to focus more on what we're doing or what we're thinking. In fact, most people find it easier to start sentences with, "I think..." instead of "I feel...
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Excerpt from huffingtonpost.com
By Amanda MacMillan
You're probably all too aware of the major sources of stress in your life -- money, your terrible commute, the construction workers who start jackhammering at 5 a.m. But stress and anxiety don't have to just come from obvious or even negative sources. "There are plenty of chronic strains and low-grade challenges that don't necessarily overwhelm you in the moment, but almost take more of a toll in the long run," says Scott Schieman, Ph.D., professor of sociology at the University of Toronto. These are some of unexpected reasons why you might feel anxious or agitated. By recognizing them for what they are, says Schieman, you can better prepare to cope.
1. Your Significant Other
Even if you have a blissfully happy relationship with your live-in partner or spouse, you're both bound to do things that get on each other's nerves. "Early in the relationship, it's usually about space and habits -- like whether you squeeze the toothpaste from the middle or the bottom of the tube," says Ken Yeager, Ph.D., associate professor of psychiatry at the Ohio State University Wexner Medical Center. "Later on, you might clash over parenting style or financial issues, and finding a unified front to face these issues together." So what's the key to surviving and thriving in your life together? Finding balance, says Yeager: spending the right amount of time together (not too much and not too little), making compromises, keeping communication open and honest, and remembering to acknowledge what you love about each other on a daily basis.
2. Everyday Annoyances
We're told not to sweat the small stuff, but sometimes it's the little things that have the biggest impact on our mood: the never-ending phone calls with your insurance company, the rude cashier at the grocery store, the 20 minutes you lose looking for a parking space. "We let these things bother us because they trigger unconscious fears," says Yeager -- fears of being seen as irresponsible, of being bullied or embarrassed, or of being late all the time, for example. "Sometimes you need to take a step back and realize that you're doing the best you can given the circumstances."
3. Other People's Stress
Stress is contagious, according to a 2014 German study: In a series of experiments, most participants who simply observed others completing a stressful task experienced an increase themselves in production of the stress hormone cortisol -- a phenomenon known as empathic stress. You can also experience stress when someone you know is affected by a traumatic event, like a car crash or a chronic illness. "You start to worry, 'Oh my gosh, could that happen to me?'," says Yeager. "We tend not to think about these things until they hit close to home."
4. Social Media
It may seem like Facebook is the only way you keep up with the friends you don't see regularly -- which, during particularly busy times, can be just about all of them. The social network also has a downside, according to a 2015 study from the Pew Research Center: It can make you aware of stressful situations in your friends' lives, which in turn can add more stress to your life. The Pew report didn't find that social media users, overall, had higher levels of stress, but previous studies have suggested that frequent social-media use can be associated with negative body image and prolonged breakup pain.
5. Distraction
A distraction can be a good thing then when it takes your mind off of a stressful situation or difficult decision, like when you take a break from work to meet a friend for lunch. But it works the other way, as well: When you're so busy thinking about something else that you can't enjoy what's going on around you, that kind of distraction can be a recipe for stress. Practicing mindfulness gives you brain the refresh it needs, says Richard Lenox, director of the Student Counseling Center at Texas Tech University. Paying full attention to your surroundings when you're walking and driving can help, he adds. "Stress and anxiety tend to melt away when our mind is focused on the present."
6. Your Childhood
Traumatic events that happened when you were a kid can continue to affect your stress levels and overall health into adulthood. A 2014 University of Wisconsin-Madison study found that these childhood experiences may actually change parts of the brain responsible for processing stress and emotion. The way you were raised can also have a lasting impact on your everyday angst, suggests a 2014 Johns Hopkins University study. Researchers found that children of parents with social anxiety disorders are more likely to develop "trickle-down anxiety" -- not simply because of their genes, but because of their parents' behaviors toward them such as a lack of warmth and emotion, or high levels of criticism and doubt.
7. Tea And Chocolate
You probably know to take it easy on the coffee when you're already feeling on edge. "Caffeine is always going to make stress worse," says Yeager. But you may not think as much about drinking several cups of tea at once, or chowing down on a bar of dark chocolate -- both of which can contain nearly as much caffeine as a cup of joe. "Chocolate is a huge caffeine source," says Yeager. "I know people who don't drink coffee but they'll eat six little candy bars in a two-hour period because they want the same kind of jolt." Too much caffeine, in any form, can cause problems with sleep, digestion, and irritability.
8. Your Expectations
When things don't go the way you've planned, do you tend to get upset and act defensively, or do you roll with the punches and set off on a new plan? If it's the former, you could be contributing to a mindset of pessimism and victimization that will slowly wear you down, even when things may not be as bad as they seem. "Your level of serenity is inversely proportionate to your expectations," says Yeager. That doesn't mean you shouldn't set ambitious goals for yourself or settle for less than what you want, of course, but being realistic about what's truly possible is important, as well.
9. Your Reaction To Stress
If you tend to deal with stressful situations by working long hours, skipping your workouts, and bingeing on junk food, we've got some bad news: You're only making it worse. "We know that physical activity and healthy foods will help your body better deal with stress, and yet we often avoid them when we need them the most," says Yeager. "People really need to think about this downward spiral we get into and work harder to counteract it."
10. Multitasking
Think you're being super efficient by tackling four tasks at once? Chances are you're not -- and it's only decreasing your productivity while increasing your stress. A 2012 University of Irvine study, for example, found that people who responded to emails all day long while also trying to get their work done experienced more heart-rate variability (an indicator of mental stress) than those who waited to respond to all of their emails at one time. Focusing on one task at a time can ensure that you're doing that job to the best of your abilities and getting the most out of it, so you won't have to worry about or go back and fix it later, says Schieman. And don't worry: You'll have enough time to do it all. In fact, you may discover you have more time than you thought.
11. Your Favorite Sport
Watching a tight game of college hoops can stress you out -- even if your alma mater wins. "The body doesn't distinguish between 'bad' stress from life or work and 'good' stress caused by game-day excitement," says Jody Gilchrist, a nurse practitioner at the University of Alabama at Birmingham’s Heart and Vascular Clinic. Watching sports can even trigger the body's sympathetic nervous system, releasing adrenaline and reducing blood flow to the heart. Those temporary consequences aren't usually anything to be concerned about, but over time, chronic stress can lead to high blood pressure and increased disease risk. And, of course, it doesn't help if you're adding alcohol and binge-eating to a situation that's already stressful on your body. You may not be able to control the outcome of the game, says Gilchrist, but you can limit its effects on your own body.
12. Digital Devices
Whether you're using it for work or play, technology may play a large role in your mental health, says Yeager. Using computers or e-readers too close to bedtime could lead to sleep problems, he says, and spending too much time virtually socializing can make real-life interactions seem extra stressful. (Plus, texting doesn't trigger the same feel-good hormones as face-to-face talk does.) Then there's the dreaded "work creep," says Schieman, when smartphones allow employees to be tethered to their jobs, even during off-hours. "People say they're only going to check email for an hour while they're on vacation, but the problem with email is that they're filled with responsibilities, new tasks, and dilemmas that are going to be hard to compartmentalize and put out of your head once that hour is up."
13. Your (Good) Health
While it may not be as stressful as having a chronic illness or getting bad news at the doctor's office, even people in the best shape of their lives worry about their bodies, their diets, and their fitness levels. In fact, people who take healthy living to an extreme may experience some rather unhealthy side effects. People who follow low-carb diets, for example, are more likely to report being sad or stressed out, while those on any kind of restrictive meal plan may feel more tired than usual. And it's not unheard of for someone to become obsessed with healthy eating (known as orthorexia) or working out (gymorexia). Like any form of perfectionism, these problems can be stressful at best, and extremely dangerous at worst.
14. Housework
Does folding laundry help you feel calm, or does it make your blood boil? If you're in a living situation where you feel you're responsible for an unfair share of work, even chores you once enjoyed may start to feel like torture. "Dividing up housework and parenting responsibilities can be tricky, especially if both partners work outside the home," says Schieman. "And whether you define that division of labor as equal or unequal can really change your attitude toward it."
15. Uncertainty
Stress can be defined as any perceived or actual threat, says Yeager, so any type of doubt that's looming over you can contribute to your anxiety levels on a daily basis. "When you know something could change at any minute, you always have your guard up and it's hard to just relax and enjoy anything." Financial uncertainty may be the most obvious stressor -- not being sure if you'll keep your job during a round of layoffs, or not knowing how you'll pay your credit card bill. Insecurities in other areas of life, like your relationship or your housing status, can eat away at you too.
16. Your Pet
No matter how much you love your furry friends, there's no question that they add extra responsibility to your already full plate. Even healthy animals need to be fed, exercised, cleaned up after, and given plenty of attention on a regular basis -- and unhealthy ones can be a whole other story. "Pets can be the most positive source of unconditional love, but at the same time they require an extreme amount of energy," says Yeager. People also tend to underestimate the stress they'll experience when they lose a pet. "I've had people in my office tell me they cried more when their dog died than when their parent died. It's a very emotional connection."
17. Your Education
Having a college degree boosts your odds of landing a well-paying job, so although you're less likely to suffer from money-related anxiety, your education can bring on other types of stress, according to a 2014 study by Schieman and his University of Toronto colleagues. His research found that highly educated people were more likely to be stressed out thanks to job pressures, being overworked, and conflicts between work and family. "Higher levels of authority come with a lot more interpersonal baggage, such as supervising people or deciding whether they get promotions," says Schieman. "With that type of responsibility, you start to take things like incompetency and people not doing their jobs more personally, and it bothers you more."
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| It now seems more probable that a collision between two planets of similar composition led to the formation of the Moon. |
Excerpt from nature.com
A nagging problem at the heart of the leading theory of how the Moon formed seems to have been explained away.
But the theory also implies that the Moon is made up mostly of impactor material. Since lunar and Earth rocks have such similar compositions, this suggests that Earth and the planet that smacked into it resembled each other too. They would have needed to be sister planets, with a relationship much closer than that of any other planetary bodies we have studied in our Solar System. The odds of this being possible were thought to be around a 1% chance, or “uncomfortably rare”, according to Robin Canup, a planetary researcher at the Southwest Research Institute in Boulder, Colorado1.
Better odds
Now it seems that the scenario is not so far-fetched, says Hagai Perets, an astrophysicist at the Israel Institute of Technology in Haifa. He and his colleagues performed simulations of the Solar System’s formation, to investigate how similar planets tend to be to their last giant impactor. They estimated that for 20% to 40% of collisions, the two bodies would be sufficiently similar to explain the Moon’s composition — considerably better odds. The findings are published in Nature2.The planets would have closely resembled each other because of their similar distance from the Sun, meaning that they would have formed from the same kind of orbiting proto-planetary material. “The Earth and the Moon are not twins born from the same planet, but they are sisters in the sense that they grew up in the same environment,” says Perets.
Excerpt from csmonitor.com
Researchers have found Jupiter-scale gas giants orbiting binary stars and estimate that Earth-like planets orbiting binary stars could be as numerous as rocky planets orbiting single-star systems.
For all the sci-fi charm of watching a pair of suns sink below a distant horizon on a planet in a galaxy far, far away, conventional wisdom has held that binary-star systems can't host Earth-scale rocky planets.
As the two stars orbit each other like square-dance partners swinging arm in arm, regular variations in their gravitational tug would disrupt planet formation at the relatively close distances where rocky planets tend to appear.
Not so fast, say two astrophysicists. They argue that only are Tatooine-like planets likely to be out there. They could be as numerous as rocky planets orbiting single-star systems – which is to say, there could be large number of them.
Building rocky planets in a binary system not only is possible, it's "not even that hard," says Scott Kenyon, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., who along with University of Utah astrophysicist Benjamin Bromley performed the calculations.
Researchers have found Jupiter-scale gas giants orbiting binary stars and have estimated that such gas giants are likely to be as common in binary systems as they are in systems with a single star.
"If that's true, then Earth-like planets around binaries are just as common as Earth-like planets around single stars," Dr. Kenyon says. "If they're not common, that tells you something about how they form or how they interact with the star over billions of years."
The modeling study grew out of work the two researchers were undertaking to figure out how the dwarf planet Pluto and its largest moon Charon manage to share space with four smaller moons that orbit the two larger objects.
Pluto and Charon form a binary system that early in its history saw the two objects graze each other to generate a ring of dust that would become the additional moons.
The gravity the surrounding dust felt as Pluto and Charon swung about their shared center of mass would vary with clock-like precision.
Conventional wisdom held that this variable tug would trigger collisions at speeds too fast to allow the dust and larger chunks to merge into ever larger objects.
Kenyon and Dr. Bromley found that, in fact, the velocities would be smaller than people thought – no greater than the speeds would be around a single central object, where velocities are slow enough to allow the debris to bump gently and merge to build ever-larger objects.
They recognized that binary stars hosting planets are essentially scaled-up versions of the Pluto-Charon system. So they applied their calculations to a hypothetical binary star system with a circumstellar disk of dust and debris.
"The modest jostling in these orbits is the same modest jostling you'd get around a single star," Kenyon says, allowing rocky inner planets to form.
As for the Jupiter- or Neptune-scale planets found around binary stars, they would have formed farther out and migrated in over time, the researchers say, since there is too little material within the inner reaches of a circumstellar disk to build giant planets.
The duo's calculations imply that as more planets are discovered orbiting binary stars, a rising number of Tatooines will be among them.
Tatooine "was science fiction," Kenyon says. But "it's not so far from science reality."
Excerpt from cnet.com
Astronomers have mapped the Milky Way's position to the outskirts of a supercluster of galaxies, newly dubbed Laniakea, meaning "Immense Heaven".
Click to zoom
But this Local Group is just a small part of a much, much bigger structure, which researchers at the University of Hawai'i Mānoa have now mapped in detail. Coming in at over 100,000 galaxies, the massive supercluster has been given the name Laniakea -- "immense heaven" in Hawaiian.
The new 3D map was created by examining the positions and movements of the 8000 closest galaxies to the Milky Way. After calculating which galaxies were being pulled away from us and which were being pulled towards us -- accounting for the universe's expansion -- the team, led by astronomer R. Brent Tully, was able to map the paths of galactic migration -- and define the boundaries of Laniakea.
Traditionally, the borders of galactic superclusters have been difficult to map, but studying the gravitational force acting on our neighbouring galaxies has provided some important clues. All objects inside Laniakea are being slowly but surely drawn to a single point -- a force known as the Great Attractor, a gravitational anomaly with a mass tens of thousands of times the mass of the Milky Way.
Everything that is being pulled towards the Great Attractor is part of Laniakea -- although it's possible that Laniakea itself might in turn be part of a structure that is larger still.
"We probably need to measure to another factor of three in distance to explain our local motion," Tully said. "We might find that we have to come up with another name for something larger than we're a part of -- we're entertaining that as a real possibility."
The full paper, "The Laniakea supercluster of galaxies", can be read online in the journal Nature.
Ceres Excerpt from cnet.com It's a real-life mystery cliffhanger. We've come up with a list of possible reasons a large crater on the biggest object in the asteroid belt looks lit up like a Christmas tree. We could be approachin...
Excerpt from csmonitor.com
Researchers at Queen Mary University of London have found the first evidence of false memories in non-human animals.
It has long been known that humans – even those of us who aren't famous news anchors – tend to recall events that did not actually occur. The same is likely true for mice: In 2013, scientists at MIT induced false memories of trauma in mice, and the following year, they used light to manipulate mice brains to turn painful memories into pleasant ones.
Now, researchers at Queen Mary University of London have shown for the first time that insects, too, can create false memories. Using a classic Pavlovian experiment, co-authors Kathryn Hunt and Lars Chittka determined that bumblebees sometimes combine the details of past memories to form new ones. Their findings were published today in Current Biology.
“I suspect the phenomenon may be widespread in the animal kingdom," Dr. Chittka said in a written statement to the Monitor.
First, Chittka and Dr. Hunt trained their buzzing subjects to expect a reward if they visited two artificial flowers – one solid yellow, the other with black-and-white rings. The order didn’t matter, so long as the bee visited both flowers. In later tests, they would present a choice of the original two flower types, plus one new one. The third type was a combination of the first two, featuring yellow-and-white rings. At first, the bees consistently selected the original two flowers, the ones that offered a reward.
But a good night’s sleep seemed to change all that. One to three days after training, the bees became confused and started incorrectly choosing the yellow-and-white flower (up to fifty percent of the time). They seemed to associate that pattern with a reward, despite having never actually seen it before. In other words, the bumblebees combined the memories of two previous stimuli to generate a new, false memory.
“Bees might, on occasion, form merged memories of flower patterns visited in the past,” Chittka said. “Should a bee unexpectedly encounter real flowers that match these false memories, they might experience a kind of deja-vu and visit these flowers expecting a rich reward.”
Bees have a rather limited brain capacity, Chittka says, so it’s probably useful for them to “economize” by storing generalized memories instead of minute details.
“In bees, for example, the ability to learn more than one flower type is certainly useful,” Chittka said, “as is the ability to extract commonalities of multiple flower patterns. But this very ability might come at the cost of bees merging memories from multiple sequential experiences.”
Chittka has studied memory in bumblebees for two decades. Bees can be raised and kept in a lab setting, so they make excellent long-term test subjects.
“They are [also] exceptionally clever animals that can memorize the colors, patterns, and scents of multiple flower species – as well as navigate efficiently over long distances,” Chittka said.
In past studies, it was assumed that animals that failed to perform learned tasks had either forgotten them or hadn’t really learned them in the first place. Chittka’s research seems to show that animal memory mechanisms are much more elaborate – at least when it comes to bumblebees.
“I think we need to move beyond understanding animal memory as either storing or not storing stimuli or episodes,” Chittka said. “The contents of memory are dynamic. It is clear from studies on human memory that they do not just fade over time, but can also change and integrate with other memories to form new information. The same is likely to be the case in many animals.”
Chittka hopes this study will lead to a greater biological understanding of false memories – in animals and humans alike. He says that false memories aren’t really a “bug in the system,” but a side effect of complex brains that strive to learn the big picture and to prepare for new experiences.
“Errors in human memory range from misremembering minor details of events to generating illusory memories of entire episodes,” Chittka said. “These inaccuracies have wide-ranging implications in crime witness accounts and in the courtroom, but I believe that – like the quirks of information processing that occur in well known optical illusions – they really are the byproduct of otherwise adaptive processes.”
“The ability to memorize the overarching principles of a number of different events might help us respond in previously un-encountered situations,” Chittka added. “But these abilities might come at the expense of remembering every detail correctly.”
So, if generating false memories goes hand in hand with having a nervous system, does all this leave Brian Williams off the hook?
“It is possible that he conflated the memories,” Chittka said, “depending on his individual vulnerability to witnessing a traumatic event, plus a possible susceptibility to false memories – there is substantial inter-person variation with respect to this. It is equally possible that he was just ‘showing off’ when reporting the incident, and is now resorting to a simple lie to try to escape embarrassment. That is impossible for me to diagnose.”
But if Mr. Williams genuinely did misremember his would-be brush with death, Chittka says he shouldn’t be vilified.
 |
| The God Particle, which is believed to be responsible for all the mass in the universe, was discovered in 2012 using a Cern's supercollider. In this image two high-energy photons collide. The yellow lines are the measured tracks of other particles produced in the collision, which helped lead to the discovery of the God particle. |
Excerpt from dailymail.co.uk
- God Particle is believed to be responsible for all the mass in the universe
- Particle was discovered in 2012 using a Cern's supercollider in Geneva
- uperconductor experiment suggests the particle could be detected without the huge amounts of energy used at by the Large Hadron Collider
- LHC is due to come back online next month after an upgrade that has given it a big boost in energy
Scientists have discovered a simulated version of the elusive 'God particle' using superconductors.
The God Particle, which is believed to be responsible for all the mass in the universe, was discovered in 2012 using a Cern's supercollider.
The superconductor experiment suggests that the Higgs particle could be detected without the huge amounts of energy used at by the Large Hadron Collider.
The results could help scientists better understand how this mysterious particle – also known as the Higgs boson – behaves in different conditions.
'Just as the Cern experiments revealed the existence of the Higgs boson in a high-energy accelerator environment, we have now revealed a Higgs boson analogue in superconductors,' said researcher Aviad Frydman from Bar-Ilan University.
Superconductors are a type of metal that, when cooled to low temperatures, allow electrons to pass through freely.
'The Higgs mode was never actually observed in superconductors because of technical difficulties - difficulties that we've managed to overcome,' Professor Frydman said.
The superconductor experiment suggests that the Higgs particle could be detected without the huge amounts of energy used at by the Large Hadron Collider (pictured)
WHAT IS THE GOD PARTICLE?
The 'God Particle', also known as the Higgs boson, was a missing piece in the jigsaw for physicists in trying to understand how the universe works.
Scientists believe that a fraction of a second after the Big Bang that gave birth to the universe, an invisible energy field, called the Higgs field, formed.
This has been described as a kind of 'cosmic treacle' across the universe.
As particles passed through it, they picked up mass, giving them size and shape and allowing them to form the atoms that make up you, everything around you and everything in the universe.
This was the theory proposed in 1964 by former grammar school boy Professor Higgs that has now been confirmed.
Without the Higgs field particles would simply whizz around space in the same way as light does.
A boson is a type of sub-atomic particle. Every energy field has a specific particle that governs its interaction with what's around it.
To try to pin it down, scientists at the Large Hadron Collider near Geneva smashed together beams of protons – the 'hearts of atoms' – at close to the speed of light, recreating conditions that existed a fraction of a second after the Big Bang.
Although they would rapidly decay, they should have left a recognisable footprint. This footprint was found in 2012.
The main difficulty was that the superconducting material would decay into something known as particle-hole pairs.
Large amounts of energy – which are usually needed to excite the Higgs mode - tend to break apart the electron pairs that act as the material's charge.
Professor Frydman and his colleagues solved this problem by using ultra-thin superconducting films of Niobium Nitrite (NbN) and Indium Oxide (InO) as something known as the 'superconductor-insulator critical point.'
This is a state in which recent theory predicted the decay of the Higgs would no longer occur.
In this way, they could still excite a Higgs mode even at relatively low energies.
'The parallel phenomenon in superconductors occurs on a different energy scale entirely - just one-thousandth of a single electronvolt,' Professor Frydman added.
'What's exciting is to see how, even in these highly disparate systems, the same fundamental physics is at work.'
The different approach help solve one of the longstanding mysteries of fundamental physics.
The discovery of the Higgs boson verified the Standard Model, which predicted that particles gain mass by passing through a field that slows down their movement through the vacuum of space.
To try to pin it down, scientists at the Large Hadron Collider near Geneva smashed together beams of protons – the 'hearts of atoms' – at close to the speed of light, recreating conditions that existed a fraction of a second after the Big Bang.
Although they would rapidly decay, the also left a recognisable footprint.
Professor Higgs, 83, has been waiting since 1964 for science to catch up with his ideas about the Higgs boson
According to Professor Frydman, observation of the Higgs mechanism in superconductors is significant because it reveals how a single type of physical process behaves under different energy conditions.
'Exciting the Higgs mode in a particle accelerator requires enormous energy levels - measured in giga-electronvolts, or 109 eV,' Professor Frydman says.
'The parallel phenomenon in superconductors occurs on a different energy scale entirely - just one-thousandth of a single electronvolt.
'What's exciting is to see how, even in these highly disparate systems, the same fundamental physics is at work.'
The LHC is due to come back online in March after an upgrade that has given it a big boost in energy.
'With this new energy level, the (collider) will open new horizons for physics and for future discoveries,' CERN Director General Rolf Heuer said in a statement.
'I'm looking forward to seeing what nature has in store for us.'
Cern's collider is buried in a 27-km (17-mile) tunnel straddling the Franco-Swiss border at the foot of the Jura mountains.
The LHC in Geneva will come back online in March after an upgrade that has given it a big boost in energy
Excerpt from sciencerecorder.com
| Armed with one of the largest telescopes in the world, the aptly named Very Large Telescope at the ESO Observatory in Chile, astronomers are conducting a search for what they once were certain had to be a brown dwarf star. The only problem is that now the star seems to have vanished without evidence. What happened? Brown dwarfs, compared to their better known red dwarf counterparts are significantly cooler, dimmer objects which at a glance bear more resemblance to planets than to other stars. Although they release heat and bear a chemical composition similar to that of the sun, astronomers tend to refer to them as “failed stars,” since they are too small to set off any thermonuclear reactions within their cores. This particular vanishing dwarf was thought to be part of a double-star system, the V471 Tauri, located within the Taurus constellation, only 163 light years from Earth. Within this system, the stars orbit each other in 12 hour intervals, which causes the brightness to diminish every six hours, when one star crosses directly in front of the other. |
However, the timing of this eclipse never happened at an entirely predictable pace, leading the researchers to suspect that a brown dwarf’s gravitational pull was pushing on the stars and causing the lapse – it’s the only thing consistent with the minimal lapsing patterns. With the use of a new powerful camera called SPHERE, they set out to plot out the location of the brown dwarf, but found nothing where they predicted it would be. “This is how science works,” said Adam Hardy, the study’s lead author who remains undaunted by the road ahead. The new study was published this week by the journal, Astrophysical Journal Letters. “Observations with new technology can either confirm or, as in this case, disprove earlier ideas.” Perhaps most intriguing is that while a brown dwarf appears to be hiding from them, the cluster it waxes influence over is among the brightest and largest of deep-sky objects visible in the evening sky. The binary star system is found in what astronomers call the Hyades cluster, named for the nymphs of Greek mythology who are responsible for the rain. |
In the recent movie “Interstellar,” set in a futuristic, downtrodden America where NASA has been forced into hiding, school textbooks say the Apollo moon landings were faked.
Excerpt from
There’s a scene in Stanley Kubrick’s comic masterpiece “Dr. Strangelove” in which Jack D. Ripper, an American general who’s gone rogue and ordered a nuclear attack on the Soviet Union, unspools his paranoid worldview — and the explanation for why he drinks “only distilled water, or rainwater, and only pure grain alcohol” — to Lionel Mandrake, a dizzy-with-anxiety group captain in the Royal Air Force.
Ripper: “Have you ever heard of a thing called fluoridation? Fluoridation of water?”Mandrake: “Ah, yes, I have heard of that, Jack. Yes, yes.”Ripper: “Well, do you know what it is?”
Mandrake: “No. No, I don’t know what it is, no.”
Ripper: “Do you realize that fluoridation is the most monstrously conceived and dangerous communist plot we have ever had to face?”
The movie came out in 1964, by which time the health benefits of fluoridation had been thoroughly established and anti-fluoridation conspiracy theories could be the stuff of comedy. Yet half a century later, fluoridation continues to incite fear and paranoia. In 2013, citizens in Portland, Ore., one of only a few major American cities that don’t fluoridate, blocked a plan by local officials to do so. Opponents didn’t like the idea of the government adding “chemicals” to their water. They claimed that fluoride could be harmful to human health.
To which some people in Portland, echoing anti-fluoridation activists around the world, reply: We don’t believe you.
We live in an age when all manner of scientific knowledge — from the safety of fluoride and vaccines to the reality of climate change — faces organized and often furious opposition. Empowered by their own sources of information and their own interpretations of research, doubters have declared war on the consensus of experts. There are so many of these controversies these days, you’d think a diabolical agency had put something in the water to make people argumentative.
Science doubt has become a pop-culture meme. In the recent movie “Interstellar,” set in a futuristic, downtrodden America where NASA has been forced into hiding, school textbooks say the Apollo moon landings were faked. The debate about mandated vaccinations has the political world talking. A spike in measles cases nationwide has President Obama, lawmakers and even potential 2016 candidates weighing in on the vaccine controversy. (Pamela Kirkland/The Washington Post)
We’re asked to accept, for example, that it’s safe to eat food containing genetically modified organisms (GMOs) because, the experts point out, there’s no evidence that it isn’t and no reason to believe that altering genes precisely in a lab is more dangerous than altering them wholesale through traditional breeding. But to some people, the very idea of transferring genes between species conjures up mad scientists running amok — and so, two centuries after Mary Shelley wrote “Frankenstein,” they talk about Frankenfood.
The world crackles with real and imaginary hazards, and distinguishing the former from the latter isn’t easy. Should we be afraid that the Ebola virus, which is spread only by direct contact with bodily fluids, will mutate into an airborne super-plague? The scientific consensus says that’s extremely unlikely: No virus has ever been observed to completely change its mode of transmission in humans, and there’s zero evidence that the latest strain of Ebola is any different. But Google “airborne Ebola” and you’ll enter a dystopia where this virus has almost supernatural powers, including the power to kill us all.
In this bewildering world we have to decide what to believe and how to act on that. In principle, that’s what science is for. “Science is not a body of facts,” says geophysicist Marcia McNutt, who once headed the U.S. Geological Survey and is now editor of Science, the prestigious journal. “Science is a method for deciding whether what we choose to believe has a basis in the laws of nature or not.”
The scientific method leads us to truths that are less than self-evident, often mind-blowing and sometimes hard to swallow. In the early 17th century, when Galileo claimed that the Earth spins on its axis and orbits the sun, he wasn’t just rejecting church doctrine. He was asking people to believe something that defied common sense — because it sure looks like the sun’s going around the Earth, and you can’t feel the Earth spinning. Galileo was put on trial and forced to recant. Two centuries later, Charles Darwin escaped that fate. But his idea that all life on Earth evolved from a primordial ancestor and that we humans are distant cousins of apes, whales and even deep-sea mollusks is still a big ask for a lot of people.Even when we intellectually accept these precepts of science, we subconsciously cling to our intuitions — what researchers call our naive beliefs. A study by Andrew Shtulman of Occidental College showed that even students with an advanced science education had a hitch in their mental gait when asked to affirm or deny that humans are descended from sea animals and that the Earth goes around the sun. Both truths are counterintuitive. The students, even those who correctly marked “true,” were slower to answer those questions than questions about whether humans are descended from tree-dwelling creatures (also true but easier to grasp) and whether the moon goes around the Earth (also true but intuitive).
Shtulman’s research indicates that as we become scientifically literate, we repress our naive beliefs but never eliminate them entirely. They nest in our brains, chirping at us as we try to make sense of the world.
Most of us do that by relying on personal experience and anecdotes, on stories rather than statistics. We might get a prostate-specific antigen test, even though it’s no longer generally recommended, because it caught a close friend’s cancer — and we pay less attention to statistical evidence, painstakingly compiled through multiple studies, showing that the test rarely saves lives but triggers many unnecessary surgeries. Or we hear about a cluster of cancer cases in a town with a hazardous-waste dump, and we assume that pollution caused the cancers. Of course, just because two things happened together doesn’t mean one caused the other, and just because events are clustered doesn’t mean they’re not random. Yet we have trouble digesting randomness; our brains crave pattern and meaning.
Even for scientists, the scientific method is a hard discipline. They, too, are vulnerable to confirmation bias — the tendency to look for and see only evidence that confirms what they already believe. But unlike the rest of us, they submit their ideas to formal peer review before publishing them. Once the results are published, if they’re important enough, other scientists will try to reproduce them — and, being congenitally skeptical and competitive, will be very happy to announce that they don’t hold up. Scientific results are always provisional, susceptible to being overturned by some future experiment or observation. Scientists rarely proclaim an absolute truth or an absolute certainty. Uncertainty is inevitable at the frontiers of knowledge.That provisional quality of science is another thing a lot of people have trouble with. To some climate-change skeptics, for example, the fact that a few scientists in the 1970s were worried (quite reasonably, it seemed at the time) about the possibility of a coming ice age is enough to discredit what is now the consensus of the world’s scientists: The planet’s surface temperature has risen by about 1.5 degrees Fahrenheit in the past 130 years, and human actions, including the burning of fossil fuels, are extremely likely to have been the dominant cause since the mid-20th century.
It’s clear that organizations funded in part by the fossil-fuel industry have deliberately tried to undermine the public’s understanding of the scientific consensus by promoting a few skeptics. The news media gives abundant attention to such mavericks, naysayers, professional controversialists and table thumpers. The media would also have you believe that science is full of shocking discoveries made by lone geniuses. Not so. The (boring) truth is that science usually advances incrementally, through the steady accretion of data and insights gathered by many people over many years. So it has with the consensus on climate change. That’s not about to go poof with the next thermometer reading.
But industry PR, however misleading, isn’t enough to explain why so many people reject the scientific consensus on global warming.
The “science communication problem,” as it’s blandly called by the scientists who study it, has yielded abundant new research into how people decide what to believe — and why they so often don’t accept the expert consensus. It’s not that they can’t grasp it, according to Dan Kahan of Yale University. In one study he asked 1,540 Americans, a representative sample, to rate the threat of climate change on a scale of zero to 10. Then he correlated that with the subjects’ science literacy. He found that higher literacy was associated with stronger views — at both ends of the spectrum. Science literacy promoted polarization on climate, not consensus. According to Kahan, that’s because people tend to use scientific knowledge to reinforce their worldviews.
Americans fall into two basic camps, Kahan says. Those with a more “egalitarian” and “communitarian” mind-set are generally suspicious of industry and apt to think it’s up to something dangerous that calls for government regulation; they’re likely to see the risks of climate change. In contrast, people with a “hierarchical” and “individualistic” mind-set respect leaders of industry and don’t like government interfering in their affairs; they’re apt to reject warnings about climate change, because they know what accepting them could lead to — some kind of tax or regulation to limit emissions.
In the United States, climate change has become a litmus test that identifies you as belonging to one or the other of these two antagonistic tribes. When we argue about it, Kahan says, we’re actually arguing about who we are, what our crowd is. We’re thinking: People like us believe this. People like that do not believe this.
Science appeals to our rational brain, but our beliefs are motivated largely by emotion, and the biggest motivation is remaining tight with our peers. “We’re all in high school. We’ve never left high school,” says Marcia McNutt. “People still have a need to fit in, and that need to fit in is so strong that local values and local opinions are always trumping science. And they will continue to trump science, especially when there is no clear downside to ignoring science.”
Meanwhile the Internet makes it easier than ever for science doubters to find their own information and experts. Gone are the days when a small number of powerful institutions — elite universities, encyclopedias and major news organizations — served as gatekeepers of scientific information. The Internet has democratized it, which is a good thing. But along with cable TV, the Web has also made it possible to live in a “filter bubble” that lets in only the information with which you already agree.
How to penetrate the bubble? How to convert science skeptics? Throwing more facts at them doesn’t help. Liz Neeley, who helps train scientists to be better communicators at an organization called Compass, says people need to hear from believers they can trust, who share their fundamental values. She has personal experience with this. Her father is a climate-change skeptic and gets most of his information on the issue from conservative media. In exasperation she finally confronted him: “Do you believe them or me?” She told him she believes the scientists who research climate change and knows many of them personally. “If you think I’m wrong,” she said, “then you’re telling me that you don’t trust me.” Her father’s stance on the issue softened. But it wasn’t the facts that did it.If you’re a rationalist, there’s something a little dispiriting about all this. In Kahan’s descriptions of how we decide what to believe, what we decide sometimes sounds almost incidental. Those of us in the science-communication business are as tribal as anyone else, he told me. We believe in scientific ideas not because we have truly evaluated all the evidence but because we feel an affinity for the scientific community. When I mentioned to Kahan that I fully accept evolution, he said: “Believing in evolution is just a description about you. It’s not an account of how you reason.”
Maybe — except that evolution is real. Biology is incomprehensible without it. There aren’t really two sides to all these issues. Climate change is happening. Vaccines save lives. Being right does matter — and the science tribe has a long track record of getting things right in the end. Modern society is built on things it got right.
Doubting science also has consequences, as seen in recent weeks with the measles outbreak that began in California. The people who believe that vaccines cause autism — often well educated and affluent, by the way — are undermining “herd immunity” to such diseases as whooping cough and measles. The anti-vaccine movement has been going strong since a prestigious British medical journal, the Lancet, published a study in 1998 linking a common vaccine to autism. The journal later retracted the study, which was thoroughly discredited. But the notion of a vaccine-autism connection has been endorsed by celebrities and reinforced through the usual Internet filters. (Anti-vaccine activist and actress Jenny McCarthy famously said on “The Oprah Winfrey Show,” “The University of Google is where I got my degree from.”)In the climate debate, the consequences of doubt are likely to be global and enduring. Climate-change skeptics in the United States have achieved their fundamental goal of halting legislative action to combat global warming. They haven’t had to win the debate on the merits; they’ve merely had to fog the room enough to keep laws governing greenhouse gas emissions from being enacted.
Some environmental activists want scientists to emerge from their ivory towers and get more involved in the policy battles. Any scientist going that route needs to do so carefully, says Liz Neeley. “That line between science communication and advocacy is very hard to step back from,” she says. In the debate over climate change, the central allegation of the skeptics is that the science saying it’s real and a serious threat is politically tinged, driven by environmental activism and not hard data. That’s not true, and it slanders honest scientists. But the claim becomes more likely to be seen as plausible if scientists go beyond their professional expertise and begin advocating specific policies.
It’s their very detachment, what you might call the cold-bloodedness of science, that makes science the killer app. It’s the way science tells us the truth rather than what we’d like the truth to be. Scientists can be as dogmatic as anyone else — but their dogma is always wilting in the hot glare of new research. In science it’s not a sin to change your mind when the evidence demands it. For some people, the tribe is more important than the truth; for the best scientists, the truth is more important than the tribe.
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In this infrared image, stellar winds from a giant star cause interstellar dust to form ripples. There's a whole lot of dust—which contains oxygen, carbon, iron, nickel, and all the other elements—out there, and eventually some of it finds its way into our bodies. Photograph by NASA, JPL-Caltech |
We have stardust in us as old as the universe—and some that may have landed on Earth just a hundred years ago.
Excerpt from National Geographic
By Simon Worrall
Astrophysics and medical pathology don't, at first sight, appear to have much in common. What do sunspots have to do with liver spots? How does the big bang connect with cystic fibrosis?
Book jacket courtesy of schrijver+schrijver
Astrophysicist Karel Schrijver, a senior fellow at the Lockheed Martin Solar and Astrophysics Laboratory, and his wife, Iris Schrijver, professor of pathology at Stanford University, have joined the dots in a new book, Living With the Stars: How the Human Body Is Connected to the Life Cycles of the Earth, the Planets, and the Stars.
Talking from their home in Palo Alto, California, they explain how everything in us originated in cosmic explosions billions of years ago, how our bodies are in a constant state of decay and regeneration, and why singer Joni Mitchell was right.
"We are stardust," Joni Mitchell famously sang in "Woodstock." It turns out she was right, wasn't she?
Iris: Was she ever! Everything we are and everything in the universe and on Earth originated from stardust, and it continually floats through us even today. It directly connects us to the universe, rebuilding our bodies over and again over our lifetimes.
That was one of the biggest surprises for us in this book. We really didn't realize how impermanent we are, and that our bodies are made of remnants of stars and massive explosions in the galaxies. All the material in our bodies originates with that residual stardust, and it finds its way into plants, and from there into the nutrients that we need for everything we do—think, move, grow. And every few years the bulk of our bodies are newly created.
Can you give me some examples of how stardust formed us?
Karel: When the universe started, there was just hydrogen and a little helium and very little of anything else. Helium is not in our bodies. Hydrogen is, but that's not the bulk of our weight. Stars are like nuclear reactors. They take a fuel and convert it to something else. Hydrogen is formed into helium, and helium is built into carbon, nitrogen and oxygen, iron and sulfur—everything we're made of. When stars get to the end of their lives, they swell up and fall together again, throwing off their outer layers. If a star is heavy enough, it will explode in a supernova.
So most of the material that we're made of comes out of dying stars, or stars that died in explosions. And those stellar explosions continue. We have stuff in us as old as the universe, and then some stuff that landed here maybe only a hundred years ago. And all of that mixes in our bodies.
Stars are being born and stars are dying in this infrared snapshot of the heavens. You and I—we come from stardust.
Photograph by NASA, JPL-Caltech, University of Wisconsin
Your book yokes together two seemingly different sciences: astrophysics and human biology. Describe your individual professions and how you combined them to create this book.
Iris: I'm a physician specializing in genetics and pathology. Pathologists are the medical specialists who diagnose diseases and their causes. We also study the responses of the body to such diseases and to the treatment given. I do this at the level of the DNA, so at Stanford University I direct the diagnostic molecular pathology laboratory. I also provide patient care by diagnosing inherited diseases and also cancers, and by following therapy responses in those cancer patients based on changes that we can detect in their DNA.
Our book is based on many conversations that Karel and I had, in which we talked to each other about topics from our daily professional lives. Those areas are quite different. I look at the code of life. He's an astrophysicist who explores the secrets of the stars. But the more we followed up on our questions to each other, the more we discovered our fields have a lot more connections than we thought possible.
Karel: I'm an astrophysicist. Astrophysicists specialize in all sorts of things, from dark matter to galaxies. I picked stars because they fascinated me. But no matter how many stars you look at, you can never see any detail. They're all tiny points in the sky.
So I turned my attention to the sun, which is the only star where we can see what happens all over the universe. At some point NASA asked me to lead a summer school for beginning researchers to try to create materials to understand the things that go all the way from the sun to the Earth. I learned so many things about these connections I started to tell Iris. At some point I thought: This could be an interesting story, and it dawned on us that together we go all the way, as she said, from the smallest to the largest. And we have great fun doing this together.
We tend to think of our bodies changing only slowly once we reach adulthood. So I was fascinated to discover that, in fact, we're changing all the time and constantly rebuilding ourselves. Talk about our skin.
Iris: Most people don't even think of the skin as an organ. In fact, it's our largest one. To keep alive, our cells have to divide and grow. We're aware of that because we see children grow. But cells also age and eventually die, and the skin is a great example of this.
It's something that touches everything around us. It's also very exposed to damage and needs to constantly regenerate. It weighs around eight pounds [four kilograms] and is composed of several layers. These layers age quickly, especially the outer layer, the dermis. The cells there are replaced roughly every month or two. That means we lose approximately 30,000 cells every minute throughout our lives, and our entire external surface layer is replaced about once a year.
Very little of our physical bodies lasts for more than a few years. Of course, that's at odds with how we perceive ourselves when we look into the mirror. But we're not fixed at all. We're more like a pattern or a process. And it was the transience of the body and the flow of energy and matter needed to counter that impermanence that led us to explore our interconnectedness with the universe.
You have a fascinating discussion about age. Describe how different parts of the human body age at different speeds.
Iris: Every tissue recreates itself, but they all do it at a different rate. We know through carbon dating that cells in the adult human body have an average age of seven to ten years. That's far less than the age of the average human, but there are remarkable differences in these ages. Some cells literally exist for a few days. Those are the ones that touch the surface. The skin is a great example, but also the surfaces of our lungs and the digestive tract. The muscle cells of the heart, an organ we consider to be very permanent, typically continue to function for more than a decade. But if you look at a person who's 50, about half of their heart cells will have been replaced.
Our bodies are never static. We're dynamic beings, and we have to be dynamic to remain alive. This is not just true for us humans. It's true for all living things.
A figure that jumped out at me is that 40,000 tons of cosmic dust fall on Earth every year. Where does it all come from? How does it affect us?
Karel: When the solar system formed, it started to freeze gas into ice and dust particles. They would grow and grow by colliding. Eventually gravity pulled them together to form planets. The planets are like big vacuum cleaners, sucking in everything around them. But they didn't complete the job. There's still an awful lot of dust floating around.
When we say that as an astronomer, we can mean anything from objects weighing micrograms, which you wouldn't even see unless you had a microscope, to things that weigh many tons, like comets. All that stuff is still there, being pulled around by the gravity of the planets and the sun. The Earth can't avoid running into this debris, so that dust falls onto the Earth all the time and has from the very beginning. It's why the planet was made in the first place.
Nowadays, you don't even notice it. But eventually all that stuff, which contains oxygen and carbon, iron, nickel, and all the other elements, finds its way into our bodies.
When a really big piece of dust, like a giant comet or asteroid, falls onto the Earth, you get a massive explosion, which is one of the reasons we believe the dinosaurs became extinct some 70 million years ago. That fortunately doesn't happen very often. But things fall out of the sky all the time. [Laughs]
Many everyday commodities we use also began their existence in outer space. Tell us about salt.
Karel: Whatever you mention, its history began in outer space. Take salt. What we usually mean by salt is kitchen salt. It has two chemicals, sodium and chloride. Where did they come from? They were formed inside stars that exploded billions of years ago and at some point found their way onto the Earth. Stellar explosions are still going on today in the galaxy, so some of the chlorine we're eating in salt was made only recently.
You study pathology, Iris. Is physical malfunction part of the cosmic order?
Iris: Absolutely. There are healthy processes, such as growth, for which we need cell division. Then there are processes when things go wrong. We age because we lose the balance between cell deaths and regeneration. That's what we see in the mirror when we age over time. That's also what we see when diseases develop, such as cancers. Cancer is basically a mistake in the DNA, and because of that the whole system can be derailed. Aging and cancer are actually very similar processes. They both originate in the fact that there's a loss of balance between regeneration and cell loss.
Cystic fibrosis is an inherited genetic disease. You inherit an error in the DNA. Because of that, certain tissues do not have the capability to provide their normal function to the body. My work is focused on finding changes in DNA in different populations so we can understand better what kinds of mutations are the basis of that disease. Based on that, we can provide prognosis. There are now drugs that target specific mutations, as well as transplants, so these patients can have a much better life span than was possible 10 or 20 years ago.
How has writing this book changed your view of life—and your view of each other?
Karel: There are two things that struck me, one that I had no idea about. The first is what Iris described earlier—the impermanence of our bodies. As a physicist, I thought the body was built early on, that it would grow and be stable. Iris showed me, over a long series of dinner discussions, that that's not the way it works. Cells die and rebuild all the time. We're literally not what were a few years ago, and not just because of the way we think. Everything around us does this. Nature is not outside us. We are nature.
As far as our relationship is concerned, I always had a great deal of respect for Iris, and physicians in general. They have to know things that I couldn't possibly remember. And that's only grown with time.
Iris: Physics was not my favorite topic in high school. [Laughs] Through Karel and our conversations, I feel that the universe and the world around us has become much more accessible. That was our goal with the book as well. We wanted it to be accessible and understandable for anyone with a high school education. It was a challenge to write it that way, to explain things to each other in lay terms. But it has certainly changed my view of life. It's increased my sense of wonder and appreciation of life.
In terms of Karel's profession and our relationship, it has inevitably deepened. We understand much better what the other person is doing in the sandboxes we respectively play in. [Laughs]
Excerpt from wired.com
In the hunt for extraterrestrial life, scientists started by searching for a world orbiting a star just like the sun. After all, the steady warmth of that glowing yellow ball in the sky makes life on Earth possible.
But as astronomers continue to discover thousands of planets, they’re realizing that if (or when) we find signs of extraterrestrial life, chances are good that those aliens will orbit a star quite different from the sun—one that’s redder, cooler, and at a fraction of the sun’s size and mass. So in the quest for otherworldly life, many astronomers have set their sights on these small stars, known as red dwarfs or M dwarfs.
At first, planet-hunting astronomers didn’t care so much about M dwarfs. After the first planet outside the solar system was discovered in 1995, scientists began hunting for a true Earth twin: a rocky planet like Earth with an orbit like ours around a sun-like star. Indeed, the search for that kind of system drove astronomers through most of the 2000s, says astronomer Phil Muirhead of Boston University.
But then astronomers realized that it might be technically easier to find planets around M dwarfs. Detecting another planet is really hard, and scientists rely on two main methods. In the first, they look for a drop in a star’s brightness when a planet passes in front of it. In the second, astronomers measure the slight wobble of a star, caused by the gentle gravitational tug of an orbiting planet. With both of these techniques, the signal is stronger and easier to detect for a planet orbiting an M dwarf. A planet around an M dwarf also orbits more frequently, increasing the chances that astronomers will spot it.
M dwarfs got a big boost from the Kepler space telescope, which launched in 2008. By staring at small patch of the sky, the telescope searches for suddenly dimming stars when a planet passes in front of them. In doing so, the spacecraft discovered a glut of planets—more than 1,000 at the latest count—it found a lot of planets around M dwarfs. “Kepler changed everything,” Muirhead said. Because M-dwarf systems are easier to find, the bounty of such planets is at least partly due to a selection effect. But, as Muirhead points out, Kepler is also designed to find Earth-sized planets around sun-like stars, and the numbers so far suggest that M-dwarfs may offer the best odds for finding life.
“By sheer luck you would be more likely to find a potentially habitable planet around an M dwarf than a star like the sun,” said astronomer Courtney Dressing of Harvard. She led an analysis to estimate how many Earth-sized planets—which she defined as those with radii ranging from one to one-and-a-half times Earth’s radius—orbit M dwarfs in the habitable zone, the region around the star where liquid water can exist on the planet’s surface. According to her latest calculations, one in four M dwarfs hosts such a planet.
That’s higher than the estimated number of Earth-sized planets around a sun-like star, she says. For example, an analysis by astronomer Erik Petigura of UC Berkeley suggests that fewer than 10 percent of sun-like stars have a planet with a radius between one and two times that of Earth’s.
This illustration shows Kepler-186f, the first rocky planet found in a star’s habitable zone. Its star is an M dwarf. 
NASA Ames/SETI Institute/JPL-Caltech
NASA Ames/SETI Institute/JPL-CaltechTo be sure, these estimates have lots of limitations. They depend on what you mean by the habitable zone, which isn’t well defined. Generally, the habitable zone is where it’s not too hot or too cold for liquid water to exist. But there are countless considerations, such as how well a planet’s atmosphere can retain water. With a more generous definition that widens the habitable zone, Petigura’s numbers for Earth-sized planets around a sun-like star go up to 22 percent or more. Likewise, Dressing’s numbers could also go up.
Astronomers were initially skeptical of M-dwarf systems because they thought a planet couldn’t be habitable near this kind of star. For one, M dwarfs are more active, especially during within the first billion years of its life. They may bombard a planet with life-killing ultraviolet radiation. They can spew powerful stellar flares that would strip a planet of its atmosphere.
And because a planet will tend to orbit close to an M dwarf, the star’s gravity can alter the planet’s rotation around its axis. When such a planet is tidally locked, as such a scenario is called, part of the planet may see eternal daylight while another part sees eternal night. The bright side would be fried while the dark side would freeze—hardly a hospitable situation for life.
But none of these are settled issues, and some studies suggest they may not be as big of a problem as previously thought, says astronomer Aomawa Shields of UCLA. For example, habitability may depend on specific types and frequency of flares, which aren’t well understood yet. Computer models have also shown that an atmosphere can help distribute heat, preventing the dark side of a planet from freezing over.
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.
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