Some black holes might kill entire galaxies

Embryonic stars can be doomed even before they are born

Black holes might kill entire galaxies with blazing energy, dooming embryonic stars before they can get born and condemning the remaining stars to a slow death, scientists have found.

Although nothing can escape from a black hole, before matter falls into one, it swirls around to form a disk that heats up as it packs together, radiating energy.

Supermassive black holes are thought to reside at the center of almost every galaxy, with some growing to billions of times the mass of our sun. To see what impact these monsters might have, researchers relied on data from the Hubble Space Telescope and the Chandra X-ray Observatory, looking for galaxies with very high X-ray emissions, a classic signature of black holes devouring gas and dust. 

The scientists discovered the accretion disks of super-massive black holes in at least one-third of all the massive galaxies in the universe far outshines the combined output of the hundreds of billions of stars in their host galaxies at some point in their histories. This outpouring of energy is high enough to strip apart every massive galaxy in the cosmos 25 times over, while the X-ray emission from them turns out to dwarf that from every other source in the universe put together.

All this radiation can drive away the gas and dust that serve as the raw ingredients of new stars, permanently shutting down star formation in the surrounding galaxy. The remaining stars age, redden, die and are never replaced.

"We are left with a startling picture of the formation history of massive galaxies, where dramatic violence in the form of the torrent of radiation from matter falling into black holes leads to the death of galaxies they inhabit," said researcher Asa Bluck, an astrophysicist at the University of Nottingham in England.

"Black holes form inside their host galaxies and grow in proportion to them, forming an accretion disc which will eventually destroy the host," he added. "In this sense they can be described as viral in nature."

Still, "massive galaxies are in the minority in our visible universe," Bluck noted. "About one in a 1,000 galaxies is thought to be massive, but it may be much less."

Many other galaxies "would be too small to harbor really massive super-massive black holes, so would be unlikely to have really dramatic outpourings of radiation leading to the death of galaxies like we see in many very massive galaxies," Bluck told SPACE.com. "However, there is still likely to be some effect from this even in small systems."

When it comes to our own galaxy, "this is actually quite a big galaxy, but has an abnormally diminutive central black hole," Bluck noted. "Currently it is in a quiescent stage — not outputting much energy — but this could change in the future."

For instance, "we expect our own galaxy and Andromeda to merge in about 4 billion years or so," Bluck explained. "If this ends up providing new gas reserves and channeling this gas to the center of our galaxy — all big ifs — then there is a real chance of triggering our dormant black hole at some point in the distant future."

"But don't worry," he added, "our sun will have sputtered out by then anyway."

Asa and his colleagues detailed their findings at the Royal Astronomical Society National Astronomy Meeting in Glasgow on April 16. They will submit their research to the Monthly Notices of the Royal Astronomical Society.

 

Plasma rocket may shorten space voyages

Rocket could take astronauts to Mars in little more than a month

An innovative plasma rocket being built as a spare for one heading to the International Space Station may have a space mission of its own: visiting an asteroid.

Equipped with an electric propulsion system, the rocket, known as Variable Specific Impulse Magnetoplasma Rocket (VASIMR), is being developed to one day transport astronauts to Mars in 39 to 45 days — a fraction of the six to nine months the trip would take with conventional chemical rockets. Shorter travel time greatly reduces astronauts' exposure to potentially deadly cosmic and solar radiation, currently a show-stopper for human missions to Mars.

Setting sail for an asteroid would be a powerful demonstration of VASIMR technology, which uses radio waves to ionize propellant — such as argon, xenon or hydrogen — and heat the resulting plasma to temperatures 20 times hotter than the surface of the sun. In place of metal nozzles to control the direction of the exhaust, VASIMR uses magnetic fields.

"All of a sudden, the future is here," said VASIMR inventor and physicist Franklin Chang-Diaz, a seven-time shuttle flier who left NASA in 2005 to start a company and work full time developing the rocket.

Chang Diaz's Houston-based Ad Astra Rocket Co., which has raised millions of dollars from private investors, reached a significant milestone last year when it successfully operated a demonstrator VASIMR at full power in a vacuum chamber.

"The engine is actually firing right now," Chang-Diaz told Discovery News. "We have lots of hurdles and challenges; we have lots of work to do. But if you look at what has happened in the last five years since we left NASA, it's been amazing."

Ad Astra plans to launch its flight version VASIMR to the space station in 2014. As a backup, Chang-Diaz intends to manufacture two engines in case a launch accident or other major problem prevents the first from reaching the outpost.

Once the engine is safely installed outside the station, the spare could be tapped for a new mission — that did not require investment by NASA.

"I had this idea that maybe there's a way we can use this backup engine that he's already building," said Rob Kelso, a former shuttle flight director at NASA's Johnson Space Center in Houston now working to build innovative partnerships between NASA and commercial firms.

While the space station's VASIMR can draw power from the outpost, a free-flying engine will need its own source. As part of the proposed asteroid mission, NASA and Ad Astra would team with the Defense Advanced Research Projects Agency to use its super-efficient, 200-kilowatt solar array currently under development.

Once the rocket reached its target asteroid, the power would be available to operate science equipment and other gear.

"You could do an extraordinary mission," Chang-Diaz said. "You don't need the power system for the rocket. Once you're there, you turn off the engine and you have 200 kilowatts to do anything you want to do. You can do all kinds of unheard of things with that level of power."

In addition to radar mapping and surveys, the mission also could pick up a sample from the asteroid and return it to Earth. Scientists are interested in learning more about where asteroids came from, how they formed and whether they carry the ingredients for life.  On a practical level, learning how asteroids are structured would be useful in case one is discovered to be on a collision course with Earth and needs to be moved.

 

Bottled-up anger hurts your heart, study says

Cardiac patients who suppressed rage had triple the risk of dying

NEW YORK - People with heart disease might want to take a careful look at how they handle their feelings of anger. A new study found that heart disease patients who suppressed their anger had nearly triple the risk of having a heart attack or dying over the next 5 to 10 years.

But this doesn't mean that angry outbursts are a better way to handle these feelings, Dr. Johan Denollet of Tilburg University in The Netherlands told Reuters Health. People tend to either vent angry feelings or hold them inside, "but I think it's important for (people) to find a midway solution to resolve these angry feelings — but in a more constructive way, a more adaptive way," Denollet said.

Anger can strangle blood flow in the heart and lead to abnormal heart rhythms, and has been linked to an increased risk of heart disease. There's also evidence that suppressing anger can be harmful to the heart. In the current study, the researchers investigated the interplay among "Type D" personality, anger, anger suppression, and outcomes in heart disease patients.

People with Type D personalities are prone to suffer from anger and other negative emotions, and find it difficult to express themselves in social situations. "This is the perfect mixture so to speak to render people more liable to chronic forms of stress and tension, which may have a negative impact," Denollet said. Type D's represent about one in five people in the general population, but as many as one in three heart disease patients, the researcher noted.

In the study, 644 patients with coronary artery disease were followed for an average of about six years, during which time 20 percent had a "major adverse cardiac event," meaning they died, had a heart attack, or underwent surgery to restore blood flow to the heart. Ten percent of the entire group died or had a heart attack during the study. Twenty-seven percent of the study participants had Type D personalities.

Anger and anger suppression were related to the risk of a major adverse event, but this relationship disappeared once the researchers took factors like blood pressure and heart disease severity into account. But a significant relationship remained between suppressed anger and the risk of heart attack or death even after the researchers adjusted for these and other factors.

While 4 percent of the patients who didn't have Type D personalities had high levels of suppressed anger, nearly 20 percent of the Type D personality patients did, the researchers found. The personality type also quadrupled the risk of having a heart attack or dying during follow-up.

The findings don't mean that people with Type D personalities or people who have a tough time expressing their anger are doomed to be unhealthy, Denollet noted. "Anger is one of the emotions that (tells) us something is not going the way we would like it to go," the researcher said. People should be aware of their angry feelings and figure out where they're coming from; "it's important to take next steps and try to do something about the situation," Denollet told Reuters Health.

For some people, according to Denollet, finding a way to speak up for themselves and discuss what's angering them with other people in a "sociable, nice way" will be enough; for others, professional help such as assertiveness training and social skills training may be warranted.

 

Good or evil deeds spur ‘superpowers’

Experiments show impact on willpower, physical strength

The mere act of kindness, or one of evil, can boost willpower and physical strength, a new study suggests.

The results, based on three experiments, show that those who performed good deeds, or envisioned themselves acting charitably, were able to hold a weight or squeeze a hand grip significantly longer than those who didn't perform or think about such deeds.

But evil acts appeared to confer similar and perhaps even greater superpowers. 

"When you think of superheroes or super villains, [you think of people] that can possess huge amounts of willpower and are relatively unfazed by pain," said study researcher Kurt Gray, a doctoral student in psychology at Harvard University in Cambridge, Mass. "And because of your stereotype of heroes and villains, you kind of embody that, or transform yourself into your perception of hero and villain," when you perform good or evil acts , he said.

Weight lifting
In one experiment, 91 volunteers were asked to hold a five-pound (about 2.3-kilogram) weight for as long as they could, and then given $1 for their efforts. About half were asked if they would like to donate their dollar to the United Nations International Children's Fund, or UNICEF. Everyone in this group agreed to donate, while those not asked of course didn't donate.

All participants were then asked to hold the weight a second time. Those who had donated to charity were able to hold the weight for an average of 53 seconds, or 7 seconds longer than those who did not donate.

In a second experiment with 151 volunteers, participants held the weight while they wrote a fictional story featuring themselves either helping, harming or not causing impact on another person.

Those who wrote about helping someone were able to hold the weight 5 seconds longer than those who wrote about a neutral interaction. Envisioning evil acts seemed to confer even more strength — those who thought about harming someone else held the weight about 8 seconds longer.

The boost in strength from evil might be because participants who thought about hurting someone needed to first conquer their conscience telling them that evil is wrong.

"Evildoers have more [agency], because they need to overcome the voice of their conscience to harm others. It takes even more agency to harm those around you," Gray said. Agency refers to the ability to have self-control, tenacity or strength.

Boosting willpowerThe findings might have implications for all areas of life in which strength or willpower is needed, Gray said.

"This suggests that the way to get more willpower is to just do good or evil, hopefully good," Gray told LiveScience. "So if you want to diet better , maybe do good before you try to avoid that dessert."

 

9 ‘harmless’ habits that age you

Little things can sabotage your efforts to slow down the clock

It pretty much goes without saying that smoking cigarettes and frying your skin in the sun make you older, so kudos for quitting and slathering on the sunscreen religiously. But if you’re trying to turn back the clock — or at least slow it down a little — don’t overlook these other habits that may be sabotaging your efforts.

1. You keep your college bedtime It’s not uncommon for superbusy women to cram a day’s worth of around-the-house to-dos into the late evening hours, a practice that pushes back bedtime into — eep! — "Late Night with Jimmy Fallon" territory. The problem with this is that too-little sleep is proving to be really, really bad for your health: Research links it to high blood pressure, diabetes, weight gain, and even just looking tired and older.

Act your age: We’re not saying you need a perfect 8 hours every single night, but make sleep a priority more often and your body will thank you. Everyone's sleep needs are different; to find out what yours are, sleep experts recommend you turn off the alarm clock when you're well rested, and see how long you naturally sleep. (Most people need 7 to 8 hours.)

2. You have a soft spot for sweets
A sugar-packed diet can take its toll on your waistline, but now experts also believe it can make your skin dull and wrinkled too. To blame is a natural process known as glycation, in which the sugar in your bloodstream attaches to proteins to form harmful new molecules called advanced glycation end products (AGEs, for short). The more sugar you eat, the more AGEs you develop; these damage surrounding proteins like collagen and elastin, which keep skin firm and elastic. Once damaged, springy and resilient collagen and elastin become dry and brittle, leading to wrinkles and sagging. These aging effects start at about age 35 and increase rapidly after that, according to a study published in the British Journal of Dermatology.

Act your age: It's not easy to eliminate sugar completely, but limiting added sugar to no more than 10% of total calories can help. If you're a 45-year-old woman of average height (5-foot-4), that's 160 calories (or 10 teaspoons) from added sugar — about the number in one 12-ounce can of Coca-Cola or six Hershey's Kisses. By comparison, the average American consumes 31 teaspoons per day of added sugar, or the equivalent of 465 calories. Watch for stealthy sugar in unexpected foods, like salad dressing. Many prepared foods contain hefty amounts of sugar, but it's hidden under aliases — including barley malt, corn syrup, dextrose, fruit juice concentrate, maltose, maple syrup, molasses, and turbinado — on ingredient panels.

3. You’re stressed more often than notYou don’t feel good when you’re stressed-out — be it from work projects piling up, a miserable commute, issues with the kids, etc. — and there’s good biological proof why you shouldn’t. Stress increases the concentration of the hormones cortisol and norepinephrine in the bloodstream, kicking up blood pressure and suppressing immunity. Over time, stress that doesn’t go away can delay healing, harden your arteries, and possibly shrink areas of your brain involved in learning, memory, and mood—talk about feeling older!

Act your age: Stress will never go away completely, but how you manage everyday blips can keep hormones on a more even — and healthy — keel. Deep breathing is the top antistress pick of Prevention advisor Andrew Weil, MD: He makes time for it at least twice a day. “It only takes 2 minutes,” he says. “I do it in the morning, when I’m falling asleep in the evening, and anytime I feel upset.” Try it: Exhale strongly through the mouth, making a whoosh sound. Breathe in quietly through the nose for a count of 4. Hold your breath for a count of 7, then exhale with the whoosh for a count of 8. Repeat the cycle 3 more times.

4. You only exercise when trying to lose weightExercise is one of the best turn-back-the-clock agents around, but too many of us don’t reap its full benefits because we only associate physical activity with weight loss. If you tend to hit the gym in 2-week stints to shed a few pounds, but then take a few months off from physical activity, you’re missing out on some major health perks. Research shows that vigorous exercisers have longer telomeres — cellular biomarkers that shorten as we age — compared with healthy adults who rarely work out. Being active consistently can help fight brain fog, reduce inflammation, and prevent type 2 diabetes and other chronic conditions that crop up over time.

Act your age: Don’t let your sneakers get dusty. Choose any activity you enjoy — be it walking, cycling, or dancing — and aim for a minimum of 20 to 25 minutes a day. Break it down, if you have to, into two 10-minute sessions. Slowly increase the frequency, duration, and intensity in small increments. If you miss a day, don’t let it become a habit; just pick up again the next day.

5. You blast your iPod
Nothing makes you feel 80 years old like having to cup your ear and say “Excuse me?” to get your friend to repeat herself … again. Hearing loss typically develops slowly, the result of prolonged exposure to thousands of high-decibel insults to the ear, many of which come from exposure to everyday gadgets, like iPods or hair dryers. MP3 players set at 50% volume can pump out sounds up to 101 decibels, well over the recommended safety threshold.

Act your age: To ageproof your iPod, keep the volume as low as possible. Use noise-canceling earbuds to block out ambient sounds, reducing your need to jack up the volume. Wear earplugs when you’re around other loud noises too, like the garbage disposal, coffee grinder, lawn mower, etc.

6. You never see your girlfriends
Your friends were probably the meat and potatoes of your social calendar back in your 20s; now you spend most of your spare time shuttling your tweens around to their various get-togethers. But here’s why making time to cultivate your friendships is so key: One study found that satisfying friendships predict longevity better than even close family ties, and they can protect against obesity, depression, and heart disease, among other health problems. No wonder you always feel reenergized after a marathon catch-up call with your best college friend or a girls’ night out with your high school crew.

Act your age: Your friends keep you young — simple as that. So if hectic schedules keep you apart, consider carving a more permanent place in your schedule for friend time. Take advantage of Facebook or e-mail groups to stay in touch on a more frequent basis — even clicking through and commenting on a pal’s recently uploaded vacation photos can help you feel closer.

7. You eat fruits and veggies — but not every day
You’ve likely heard that antioxidant-packed fruits and veggies can help you stay young. These powerful compounds fight free radicals that would otherwise wreak havoc on your body and skin, damaging cells that can lead to cancer and make you look older. But here’s the rub: Antioxidants remain active for only a few hours and need to be continually replenished, so don't think you're set for the week after eating a big salad for lunch on Monday.

Act your age: ODing on veggies a couple of days a week or month—and skipping them the rest of the time—doesn’t do your body any favors. To truly maximize their age-defying benefits, aim to eat antioxidants every 4 hours or so or with every meal.

8. You’ve shunned all fat from your diet
Cutting out artery-clogging saturated and trans fats is a heart-healthy move, but when it comes to your health and vitality, equally slashing unsaturated fats, like those found in fish, nuts, and olive oil, is like throwing the proverbial baby out with the bathwater. One kind, omega-3 fatty acids, is the ultimate anti-aging fat, essential for protecting your brain, heart, bones, joints, skin, and more. Another kind, monounsaturated, can lower bad LDL cholesterol, raise cardio-protective HDL cholesterol, and decrease your risk of atherosclerosis. Plus, studies suggest that a higher intake of these fats may contribute to longer life expectancy.

Act your age: Remember that fat isn’t inherently evil, and it won’t make you fat per se. About 20 to 35% of your daily calories should come from fat (mainly healthy, unsaturated fat) like those from the above sources.

9. You can’t remember the last time you had sexYep, sex feels good and does wonders for your mood, but it’s also fantastically great for your health. Research shows that people with active sex lives have stronger immune systems, less pain, a lower cancer risk, healthier hearts, and less stress. The best news: It can even make you look younger — up to 12 years, a study shows.

Act your age: Rekindle the romance between you and your partner. To shake things up, try making the first move next time. “Some women are not active participants in their sex lives,” says Pat Covalt, PhD, author of What Smart Couples Know. “A lot of men would like to be touched more, seduced more. Everyone wants to feel wanted.”

 

Viewers prove ‘Dancing’ no day at the beach

Despite strong Viennese waltz, Pamela Anderson sent packing

“Dancing With the Stars” viewers sent former “Baywatch” babe Pamela Anderson home on Tuesday night. Anderson received a combined score of 51 for her Viennese waltz on Monday.

Erin Andrews and partner Maksim Chmerkovskiy, who also received a combined score of 51 on Monday night, joined Anderson and partner Damian Whitewood in the bottom two.

Niecy Nash received the lowest overall score during Monday's performance show (49 points) but was among the top three on Tuesday. Also among the top three were Evan Lysacek and Nicole Scherzinger.

When all is said and done, the season is quickly turning into the Evan Versus Nicole Show. And while Nicole is unquestionably the more skilled technical dancer, it's looking more and more like Evan might grab it away from her.

If indeed Nicole can't win despite her high skill level, why? Her first problem is that she has no way to improve. She was already a professional dancer when the season started, and there are no surprises left in her bag of tricks. The only thing the judges can ever find to take away from her is Derek Hough's unconventional choreography, and the audience certainly isn't going to suddenly be impressed when the choreography becomes more conventional.

It's not that the show isn't trying to leave her room for improvement. In fact, the struggle to hold down her scores has grown downright silly. Carrie Ann Inaba watched Nicole's waltz, called her the best dancer the show has ever had in 10 seasons by far and then awarded her … a 9 (as did the other judges).

Viewers probably aren't buying this "Nicole isn't any better than anyone else" narrative, however. It's very hard to win without momentum, and Nicole has no way of getting momentum.

 

Lack of sleep 'linked to early death'

Getting less than six hours sleep a night can lead to an early grave, UK and Italian researchers have warned.

They said people regularly having this little sleep were 12% more likely to die over 25 years or less than those who got an "ideal" six to eight hours.

They also found an association between sleeping for more than nine hours and early death, although that much sleep may merely be a marker of ill health.

Sleep journal reports the findings, based on 1.5m people in 16 studies.

The study looked at the relationship between sleep and mortality by reviewing earlier studies from the UK, US and European and East Asian countries.

Premature death from all causes was linked to getting either too little or too much sleep outside of the "ideal" six to eight hours per night.

But while a lack of sleep may be a direct cause of ill-health, ultimately leading to an earlier death, too much sleep may merely be a marker of ill health already, the UK and Italian researchers believe.

Time pressures

Professor Francesco Cappuccio, leader of the Sleep, Health and Society Programme at the UK's University of Warwick, said: "Modern society has seen a gradual reduction in the average amount of sleep people take and this pattern is more common amongst full-time workers, suggesting that it may be due to societal pressures for longer working hours and more shift-work.

"On the other hand, the deterioration of our health status is often accompanied by an extension of our sleeping time."

If the link between a lack of sleep and death is truly causal, it would equate to over 6.3 million attributable deaths in the UK in people over 16 years of age.

Prof Cappuccio said more work was needed to understand exactly why sleep seemed to be so important for good health.

Professor Jim Horne, of the Loughborough Sleep Research Centre, said other factors may be involved rather than sleep per se.

"Sleep is just a litmus paper to physical and mental health. Sleep is affected by many diseases and conditions, including depression," he said.

And getting improved sleep may not make someone better or live longer, he said.

"But having less than five hours a night suggests something is probably not right.

"Five hours is insufficient for most people and being drowsy in the day increases your risk of having an accident if driving or operating dangerous machinery."