Strange dark stuff is making the universe too bright

LIGHT is in crisis. The universe is far brighter than it should be based on the number of light-emitting objects we can find, a cosmic accounting problem that has astronomers baffled.

"Something is very wrong," says Juna Kollmeier at the Observatories of the Carnegie Institution of Washington in Pasadena, California.

Solving the mystery could show us novel ways to hunt for dark matter, or reveal the presence of another unknown "dark" component to the cosmos.

"It's such a big discrepancy that whatever we find is going to be amazing, and it will overturn something we currently think is true," says Kollmeier.

The trouble stems from the most recent census of objects that produce high-energy ultraviolet light. Some of the biggest known sources are quasars – galaxies with actively feeding black holes at their centres. These behemoths spit out plenty of UV light as matter falling into them is heated and compressed. Young galaxies filled with hot, bright stars are also contributors.

Ultraviolet light from these objects ionises the gas that permeates intergalactic space, stripping hydrogen atoms of their electrons. Observations of the gas can tell us how much of it has been ionised, helping astronomers to estimate the amount of UV light that must be flying about.

But as our images of the cosmos became sharper, astronomers found that these measurements don't seem to tally with the number of sources found.

Kollmeier started worrying in 2012, when Francesco Haardt at the University of Insubria in Como, Italy, and Piero Madau at the University of California, Santa Cruz, compiled the results of several sky surveys and found far fewer UV sources than previously suggested.

Then in February, Charles Danforth at the University of Colorado, Boulder, and his colleagues released the latest observations of intergalactic hydrogen by the Hubble Space Telescope. That work confirmed the large amount of gas being ionised. "It could have been that there was much more neutral hydrogen than we thought, and therefore there would be no light crisis," says Kollmeier. "But that loophole has been shut."

Now Kollmeier and her colleagues have run computer simulations of intergalactic gas and compared them with the Hubble data, just to be sure. They found that there is five times too much ionised gas for the number of known UV sources in the modern, nearby universe.

Strangely, their simulations also show that, for the early, more distant universe, UV sources and ionised gas match up perfectly, suggesting something has changed with time (Astrophysical Journal Letters,doi.org/tqm).

This could be down to dark matter, the mysterious stuff thought to make up more than 80 per cent of the matter in the universe.

The leading theoretical candidates for dark matter are weakly interacting massive particles, or WIMPs. There are many proposed versions of WIMPs, including some non-standard varieties that would decay and release UV photons.

Knowing that dark matter in the early universe worked like a scaffold to create the cosmic structure we see today, we have a good idea how much must have existed in the past. That suggests dark matter particles are stable for billions of years before they begin to decay.

Theorists can now consider the UV problem in their calculations and see if any of the proposed particles start to decay at the right time to account for the extra light, says Kathryn Zurek, a dark matter expert at the University of Michigan in Ann Arbor. If so, that could explain why the excess only shows up in the modern cosmos.

If WIMPS aren't the answer, the possible explanations become even more bizarre, such as mysterious "dark" objects that can emit UV light but remain shrouded from view. And if all else fails, there's even a chance something is wrong with our basic understanding of hydrogen.

"We don't know what it is, or we would be reporting discovery instead of crisis," says Kollmeier. "The point is to bring this to everyone's attention so we can figure it out as a community."

This article appeared in print under the headline "Why is the cosmos too bright to bear?"

• 17 July 2014 by Lisa Grossman

In Tanzania, ‘Living Walls’ Take Root to Protect Threatened Lions

Elvis Kisimir is a moon-faced and soft-spoken 31-year-old Maasai with a fondness for lions. That makes him the odd man out in the East African tribe of pastoralists whose conflict with the big cats is legendary.

But Elvis has a vision for the future that’s every bit as large as the history that precedes him. That vision is the Living Wall project — an effort to radically change not just his peoples’ interactions with lions but the very way they think of the animals, which are now critically endangered in the region.

“This work is my life now,” he told me. “I want this area to be an example for the world of a functioning, healthy ecosystem where both people and wildlife live in harmony together.”

A Fierce History

The Maasai are perhaps best known for their coming-of-age ritual in which young morani warriors venture into the bush draped in bright red waistcloths, armed only with spears, to kill a lion as a traditional test of manhood. Nowadays, however, this practice is on the wane. Maasai adolescents — like their peers elsewhere in Africa — tend to be more adept with soccer balls and video games than they are with spears and the ancient art of tracking carnivores through the open bush.

That was certainly true of the young Elvis. Aside from occasionally hearing their roars at night, he had little contact with lions growing up in a village on Tanzania’s Maasai Steppe. His first encounter with the king of beasts came from a video about their social life, which his tour-guide father brought home with him one day.

It was not exactly a case of love at first sight. The big cats appeared scary and alien, a relic of the wild Africa that Elvis and his Christian forebears (his grandfather was one of the first Maasai to be baptized) had presumably left behind them.

Still, his curiosity was aroused. When Elvis asked his Maasai elders about lions, they spoke of the respect with which the species was regarded in their culture: though they were hunted, at the same time lions were deeply admired as embodiments of independence, courage, canny intelligence and majestic strength.

Changing Times

This traditional bond with lions among the Maasai is now fraying. Former Maasai nomads are becoming sedentary, many taking up farming, and the population in the region is booming, with people from other tribal groups moving into their traditional territory. Climate change is also causing inconsistent rainfall, which is drying out the rangeland, forcing the Maasai to search even harder to find forage for their livestock.

These changes have put increasing pressure on the region’s wildlife as well, which frequently finds itself in conflict with humans over limited resources. Lions come into villages at night to kill livestock, and the Maasai retaliate by killing lions, not in the traditional way with spears, but more often with poisoned meat and guns, sometimes wiping out whole prides at a time.

“The lions just don’t roar like they used to,” Elvis says.

More widely, big cats are in crisis throughout Africa. There may be as few as 400 lions left in the whole of West Africa, where much of their historical habitat has been converted into farmland. On the vast savannahs of southern and the eastern Africa, of which Tanzania is a part, their populations have also dwindled — down to an estimated 30,000 from over 90,000 animals 50 years ago.

Elvis worried that if the lions disappeared, the Maasai would be in danger of their cultural identity disappearing too.

Living Walls

In 2010, Elvis interviewed for a job as a program officer for the African People and Wildlife Fund — and that was when he met Mama Simba (“mother lion”).

Mama Simba’s real name is Laly Lichtenfeld; the moniker was given to her by the local Maasai because of her zealous advocacy for the species. Elvis was intrigued by her plan to build new fences to protect the cattle — the corrals made of thorny bushes that many local people used were permeable and difficult to maintain.

Laly proposed building a new kind of fence, made of wooden poles and chain link, that could not be penetrated by lions. But like other Maasai, Elvis didn’t like the idea of using wooden poles, which could rot and would need frequent replacement. Why not use living trees instead, he suggested — like the African myrrh, which the Maasai traditionally use as the outer wall of their family enclosures?

Thus was born the idea for the Living Walls. Over time, Elvis worked together with other Maasai to tweak the design for the fences, reinforcing the gates and digging the chain link into the ground to prevent incursions.

The Living Wall team strip limbs from the myrrh trees in the dry season, let them dry out, and then stick the limbs in the ground and wait for the rains, when the seemingly dead poles sprout to life. Then they affix the chain link to the growing trees. As the tree root systems spread, they prevent honey badgers and hyenas from tunneling under the fence, while the thickening tree canopies prevent lions from getting in from above.

At Peace With Lions

There are now over 350 such livestock enclosures in use, and Elvis’s team of local builders cannot put them up them fast enough to meet the growing demand. The Maasai themselves cover a portion of the cost for the fence on their land, while the African People and Wildlife Fund — for whom Elvis now works — pays the rest. In return, recipients must pledge that they will not engage in retribution attacks. Previously nearly 60 lions were killed annually in retribution attacks in the region surrounding Tarangire National Park; since the fences started being built in 2008, that number is down to 10 or fewer.

Earlier this year, the Tanzanian government received funding from the United Nations Development Program to bring Living Walls elsewhere in Tanzania. Elvis regularly travels to Longido District near the Kenyan border to train people there on how to install them. The idea has also spread into Kenya, where the walls are being built near Amboseli National Park, as well as to Mozambique.

Equally important as building the fences, says Elvis, is educating villagers, and especially the young. Occasionally even now a band of morani ventures out to kill a lion. “When that happens,” Elvis says, “I join them. I don’t try to stop them. But then I start to talk about what amazing animals lions are, and how important they are in Maasai culture. They slow down and listen. Because I am their elder, they pay attention to what I say.”

The young warriors are so intrigued to hear Elvis share his knowledge and passion for lions that they forget they are out to kill one, he says with a chuckle. Eventually they call off the hunt.

“I want to help people to eliminate their fear of living with lions,” says Elvis. “I want them to understand that when lions are healthy the ecosystem is healthy and in balance and the Maasai community is also healthy.”

As this message begins to spread, peace is breaking out between lions and their human neighbors in one small corner of Tanzania.

By Richard Schiffman | July 16, 2014 10:00 am

Computer Models Show What Exactly Would Happen To Earth After A Nuclear War

You've seen what a nuclear winter looks like, as imagined by filmmakers and novelists. Now you can take a look at what scientists have to say. In a new study, a team of four U.S. atmospheric and environmental scientists modeled what would happen after a "limited, regional nuclear war." To inexpert ears, the consequences sound pretty subtle—two or three degrees of global cooling, a nine percent reduction in yearly rainfall. Still, such changes could be enough to trigger crop failures and famines. After all, these would be cooler temperatures than the Earth has seen in 1,000 years.

Let's take a detailed look at some of these super-fun conclusions, shall we?

First, what happened?

The team imagines 100 nuclear warheads, each about the size of the atomic bomb the U.S. dropped on Hiroshima, detonate over the Indian subcontinent. The team members are imagining an India-Pakistan nuclear war. It seems unfair to single out these nations, but I guess they're the poster children because they have relatively small nuclear stockpiles compared to countries such as the U.S., Russia and China. The idea is, If these lightweights can do this to Earth, imagine what the bigwigs can do.

After the Indian-Pakistani nuclear exchange…

• Five megatons of black carbon enter the atmosphere immediately. Black carbon comes from burned stuff and it absorbs heat from the sun before it can reach the Earth. Some black carbon does eventually falls back to Earth in rain.
• After one year, the average surface temperature of the Earth falls by 1.1 kelvin, or about two degrees Fahrenheit. After five years, the Earth is, on average, three degrees colder than it used to be. Twenty years on, our home planet warms again to about one degree cooler than the average before the nuclear war.
• Earth's falling temperatures reduces the amount of rain the planet receives. Year five after the war, Earth will have 9 percent less rain than usual. Year 26 after the war, Earth gets 4.5 percent less rain than before the war.
• In years 2-6 after the war, the frost-free growing season for crops is shortened by 10 to 40 days, depending on the region.
• Chemical reactions in the atmosphere eat away Earth's ozone layer, which protects Earth's inhabitants from ultraviolet radiation. In the five years after the war, the ozone is 20 to 25 percent thinner, on average. Ten years on, the ozone layer has recovered so that it's now 8 percent thinner.
• The decreased UV protection may lead to more sunburns and skin cancers in people, as well as reduced plant growth and destabilized DNA in crops such as corn.
• In a separate study, published in 2013, International Physicians for the Prevention of Nuclear War estimated 2 billion people would starve in the wake of a 100-A-bomb war.

Okay, I know I've just made your day with this list. Still, there's a point to all this doom and gloom, the modelers write in their paper. The scientists want to motivate countries to destroy the estimated 17,000 nuclear weapons they still hold.

Will this work? Well, scientists and artists have been imagining the dire consequences of an atom-bomb war for decades. The very idea of a "nuclear winter" entered the popular imagination in 1983, when a study, authored by a team including Carl Sagan, first proposed that soot from fires after a nuclear war would block sunlight from reaching Earth.

Twenty-five years later, environmental scientists began using modern climate models to figure out what might happen after a nuclear war. Yep, these are the same models that scientists use to predict the effects of human-driven global warming. This new paper combined a number of those state-of-the-art models. If you check out the paper, published in the journal Earth's Future, you can see how these conclusions compare to previous climate-model-based calculations. Different modeling efforts have come up with slightly different years for when the Earth would be coldest after a nuclear war, for example, but they generally agree that the effects would be, well, severe and long-term.

By Francie Diep

New map fingers future hot spots for U.S. earthquakes

Earthquake risk assessments can seem pretty abstract at first glance, with their “percent probabilities” and “peak ground accelerations.” But the U.S. Geological Survey’s (USGS’s) national hazard maps, updated periodically, pack a powerful punch: Insurance companies and city planners rely heavily on the maps, which influence billions of dollars in construction every year. Today, USGS scientists released the most recent earthquake hazard assessments for the country. Although the picture hasn’t changed much on a national scale since the last report in 2008, the devil is in the details, the report’s authors say—and some areas in the country are now considered to be at higher risk for powerful quakes than once thought.

The best-known earthquake zones—California, the Pacific Northwest, and the Intermountain West—still dominate the hazard picture. Farther east, hot spots around the New Madrid Seismic Zone in the center of the country and Charleston, South Carolina, reflect the memory of powerful historical quakes (in 1811 to 1812 and 1886, respectively). But, in fact, all 50 states have the potential for earthquakes, and damaging ground shaking could happen in 42 of the 50 states within 50 years, the new report suggests. Of those, 16 states, all of which have had earthquakes of at least magnitude 6 in historical times, are considered highly likely to experience damaging ground shaking.

To assess the risk of where and how often future earthquakes will occur, and how hard the ground will shake, scientists are constantly seeking new data from these regions and using them to develop new ways of modeling ground motion, says Mark Petersen, a seismologist at USGS in Golden, Colorado, and the lead author of the new report. Among the latest temblors incorporated into the assessment is the 2011 5.8-magnitude Virginia earthquake, which “helped us understand better ground shaking in the central and eastern United States,” Petersen says. New data also came from the U.S. Nuclear Regulatory Commission (NRC), which in 2010 published its own risk assessment for earthquake damage to its power plants in the central and eastern United States. These all suggest the region has the potential to experience an even more powerful quake. 

Modern earthquake risk in the New Madrid Seismic Zone—which experienced three powerful quakes 200 years ago but nothing on that order since—remains a bone of contention. Some seismologists—most notably Seth Stein of Northwestern University in Evanston, Illinois—contend that ongoing quakes in the region are aftershocks of the three big ones, not signs of new seismic activity, and that USGS is overestimating the risk there. However, others dispute this; a paper published in Science earlier this year suggested that the region is still very much alive. All of this makes for a headache for those trying to sort out appropriate building codes and engineering designs; to try to bring some harmony to the dispute, the latest hazard assessment incorporated a model that followed some of Stein’s ideas, including using GPS to detect tectonic strain in the region, as well as the data from NRC. The result—though unlikely to settle the debate anytime soon—was “a broader range of [earthquake] magnitudes and recurrence rates for New Madrid than we had before,” Petersen says.

In California, the 2014 assessment has been significantly adjusted, thanks in large part to the brand-new Uniform California Earthquake Rupture Forecast model, which allows scientists to come up with rupture scenarios that are “plausible” for the state’s complex network of faults, Petersen says. That changed the hazards on a highly local basis, but also extended the potential for damage farther across the state.

Some of the biggest change in earthquake risk is in the Cascadia Subduction Zone, which extends from British Columbia down to northern California. The powerful shaking from several recent subduction zone earthquakes around the world—notably the 9.0-magnitude Tohoku earthquake in 2011 and the 8.2-magnitude quake off the coast of Chile in 2014—and geologic evidence from deep-sea cores of powerful quakes in the past now suggest that southern Cascadia could experience an earthquake as powerful as magnitude 9.3.

One thing the new report doesn’t include is hazard due to induced seismicity—earthquakes related to human activities, such as reintroducing wastewater into injection wells. That’s a layer that USGS plans to include, Petersen says—but right now, it’s not quite clear how to do it. “We basically want to treat them separately from the other earthquakes,” he adds, because mapping the hazards from human activities requires “a different logic tree.” USGS is now planning regional workshops to discuss how to incorporate the hazard into its next generation of maps.

There is indeed a growing sense of urgency to the question. “I think it’s incredibly striking what’s happened the last few years with the increase of seismicity in the eastern and central U.S.,” says Emily Brodsky, a seismologist at the University of California, Santa Cruz. “It really changes the story and the hazard implications. We’re dealing with places that historically have not thought a lot about earthquakes.”

It’s still an open question whether human-induced earthquakes will actually rupture in similar ways to natural quakes, Brodsky adds. “That is the question we really need to assess—whether or not anything is different physically, or whether they’ll interact, have connected ruptures.” And that’s one of the big general innovations in the new report, she adds—incorporating the way ruptures will actually connect and interact with one another, potentially creating a much larger and more catastrophic event than would occur from an individual rupture. Modeling rupture connectivity doesn’t just apply to California’s complicated network of faults—it can also have implications for the hazard assessed from induced quakes, she says.

By Carolyn Gramling

Carolyn is a staff writer for Scienceand is the editor of the In Brief section.

Scientists rebuild ocean in the middle of desert

An artificial ocean in the Arizona desert is on the rise—again. A biosphere built there in 1991 by a team studying space colonization contains a 676,000-gallon ocean that once had a healthy coral reef. The project eventually collapsed, and now a University of Arizona marine biologist is planning to revive the waters with organisms like starfish, sea urchins, and horn sharks. The hope is that the artificial sea will eventually serve as a laboratory for other researchers and engineers, National Geographic reports.

Source: National Geographic

Report: Climate changing more rapidly than at any point on record

A new look at the “vital signs” of Earth’s climate reveals a stark picture of declining health. As global temperatures rise, so do sea level and the amount of heat trapped in the ocean’s upper layers. Meanwhile, mountain glaciers and Arctic sea ice are melting away beneath an atmosphere where concentrations of three key planet-warming greenhouse gases continue to rise.

“Data show that the climate is changing more rapidly now than it has at any time in the historical record,” says Thomas Karl, director of the National Oceanic and Atmospheric Administration’s (NOAA’s) National Climatic Data Center in Asheville, North Carolina. “The numbers speak for themselves.”

The numbers speak pretty loudly, too. Depending on which data set scientists look at, 2013 falls somewhere between the second warmest and sixth warmest year since record keeping began in 1880. Global sea level reached a new record high last year—about 3.8 centimeters (1.5 inches) above the average measured by satellites between 1993 and 2010. Overall, sea level is rising about 3 millimeters (one-eighth of an inch) each year. And for the 23rd straight year, mountain glaciers on the whole lost more ice than they gained, says Jessica Blunden of ERT Inc., who works with Karl at the climate monitoring agency in Asheville. “Changes in these [glaciers] are visible and obvious signs of climate change,” Blunden says.

The new study, State of the Climate in 2013, was released online today in the Bulletin of the American Meteorological Society. The detailed, peer-reviewed analysis was based on data from environmental monitoring stations on land, sea, and ice and from sensors on satellites and planes. More than 400 scientists from 57 countries contributed to the report. (Previous State of the Climate reports, issued annually since 1991, can be found here.)

Increases in the levels of three key greenhouse gases are likely to be the root of recent warming, scientists suggest. The global average concentration of carbon dioxide reached more than 395 parts per million last year, a 2.8 ppm increase over 2012 levels, according to the new report. Levels of both methane and nitrous oxide (N2O), which on a pound-for-pound basis trap heat more effectively than CO2, rose last year about 0.3%. (Nevertheless, about two-thirds of the atmosphere’s heat-trapping power comes from CO2, which is much more prevalent than the other two gases, the researchers report. Carbon dioxide levels are now in uncharted territory, the scientists say: Ice core records reveal that until the early 20th century, CO2 concentrations hadn’t risen above 300 ppm during the previous 800,000 years.)

From pole to pole, few parts of the globe are being spared warm-up. In the Eurasian Arctic, average temperatures last summer ranged between 1°C and 3°C warmer than the average temperatures there from 2007 through 2012. Fairbanks, Alaska, had a record number of days (36) in which the daily high temperature reached 27°C (80°F) or higher. All that warmth is seeping into the ground, too. Permafrost temperatures measured 20 meters below ground at many sites in Alaska reached record highs last year, the scientists report. And 2013’s Arctic sea ice coverage in September, the month it usually falls to its lowest for the year, was 18% below the average coverage for that month from 1981 through 2010. Although not a record low amount, the scientists note that September sea ice coverage is declining almost 14% per decade since satellites started measuring sea ice extent in 1979.

At the other end of Earth, 2013’s average annual temperature at the South Pole was –47.4°C (–53.3°F): chilly, yes, but nevertheless a record high since scientists started collecting weather data there in 1957.

In between, China, Japan, and South Korea suffered their warmest summer on record, and Australia really suffered: With large swaths of the Land Down Under tallying summertime highs above 45°C (113°F), Australia had its warmest year since record keeping began in 1910.

The amount of heat stored in the upper 700 meters of the world’s oceans, which has increased substantially over the past 2 decades, also reached a record level last year. That increased heat content helps boost the strength of typhoons and hurricanes, Karl suggests. In the next couple of months, he notes, NOAA will release a report that discusses how climate change might be related to several episodes of extreme weather last year.

By Sid Perkins

Sid is a freelance science journalist.

Hardcore pot smoking could damage the brain's pleasure center

It probably won’t come as a surprise that smoking a joint now and then will leave you feeling … pretty good, man. But smoking a lot of marijuana over a long time might do just the opposite.

Scientists have found that the brains of pot abusers react less strongly to the chemical dopamine, which is responsible for creating feelings of pleasure and reward. Their blunted dopamine responses could leave heavy marijuana users living in a fog—and not the good kind.

After high-profile legalizations in Colorado, Washington, and Uruguay, marijuana is becoming more and more available in many parts of the world. Still, scientific research on the drug has lagged. Pot contains lots of different chemicals, and scientists don’t fully understand how those components interact to produce the unique effects of different strains. Its illicit status in most of the world has also thrown up barriers to research. In the United States, for example, any study involving marijuana requires approval from four different federal agencies, including the Drug Enforcement Administration. Politics also plays a role in marijuana research.

One of the unanswered questions about the drug is what, exactly, it does to our brains, both during the high and afterward. Of particular interest to scientists is marijuana’s effect on dopamine, a main ingredient in the brain’s reward system. Pleasurable activities such as eating, sex, and some drugs all trigger bursts of dopamine, essentially telling the brain, “Hey, that was great—let’s do it again soon.”

Scientists know that drug abuse can wreak havoc on the dopamine system. Cocaine and alcohol abusers, for example, are known to produce far less dopamine in their brains than people who aren’t addicted to those drugs. But past studies had hinted that the same might not be true for those who abuse marijuana.

Nora Volkow, the director of the National Institute on Drug Abuse in Bethesda, Maryland, decided to take a closer look at the brains of marijuana abusers. For help, she and her team turned to another drug: methylphenidate (aka Ritalin), a stimulant known to increase the amount of dopamine in the brain. The researchers gave methylphenidate to 24 marijuana abusers (who had smoked a median of about five joints a day, 5 days a week, for 10 years) and 24 controls.

Brain imaging revealed that both groups produced just as much extra dopamine after taking the drug. But whereas the controls experienced increased heart rates and blood pressure readings and reported feeling restless and high, the marijuana abusers didn’t. Their responses were so weak that Volkow had to double-check that the methylphenidate she was giving them hadn’t passed its expiration date.

This lack of a physical response suggests that marijuana abusers might have damaged reward circuitry in their brains, Volkow and her team report online today in the Proceedings of the National Academy of Sciences. Unlike cocaine and alcohol abusers, marijuana abusers appear to produce the same amount of dopamine as people who don’t abuse the drug. But their brains don’t know what to do with it. This disconnect could be “a key mechanism underlying cannabis addiction,” says Raul Gonzalez, a neuropsychologist at Florida International University in Miami who was not involved with the research. The study “suggests that cannabis users may experience less reward from things others generally find pleasurable and, contrary to popular stereotypes, that they generally feel more irritable, stressed, and just plain crummy. This may contribute to ongoing and escalating cannabis use among such individuals.”

But do marijuana abusers smoke a lot because they feel crummy, or do they feel crummy because they smoke a lot? Volkow doesn’t know. Not being able to tease out cause and effect “is a limitation in a study like this one,” she says. Perhaps the abusers already had less reactive dopamine systems and started smoking a ton of pot to cope with their general malaise. Or maybe prolonged marijuana abuse is actually damaging their brains’ reward circuitry, leading to the apathy and social withdrawal that marijuana abusers often experience.

The lessons for recreational users of marijuana, if any, are unclear. This study used “hardcore volunteer[s]” who were “using quite a lot of cannabis,” says Paul Stokes, a psychiatrist at Imperial College London who wasn’t involved in the research. As such, “it probably tells you more about cannabis dependence than about recreational use.” But when he did a similar brain imaging study of people who smoked marijuana no more than once a week, he observed “similar themes” when it came to dopamine.

All of these are important questions to answer, Volkow says. As availability of the drug increases, she says, it’s something “we all need to know.”

By 

Lizzie Wade

Lizzie is Science's Latin America correspondent, based in Mexico City.

NASA Seeks Extraterrestrial Life in Universe

Extraterrestrial life is seen from the television and big screen every year. NASA is looking to turn the theory of fiction into universal exploratory endeavors. Earlier this week at NASA headquarters in Washington, a panel of space program scientists dropped an amazing goal. They estimate it will take approximately 20 years for Earthlings to find alien life. The agency is so focused on this initiative they will launch the Transiting Exoplanet Surveying Satellite in just three years. The specialists shared there could be as many as 100 million words within the Milky Way galaxy housing a form of alien life.

One of the focal points of exploration is none other than Jupiter’s moon, Europa. The icy world of Europa is slightly smaller than the Earth’s moon. It is possible Europa houses an ocean with a rocky seafloor, beneath its icy cloak. If scientists can prove water exists on the orb, it can open doors of opportunity.

For centuries the age-old question of “are we alone?” has haunted scientists, and they intend to finally place their questions to rest. NASA has a space mission planned for Europa by the early 2020s, knowing it can take a few years to land on its potential surface. The agency will select 20 proposals in the spring of 2015 to receive funding to begin instrument development for the planned travel. Over the past few years, NASA has monitored Europa and discovered “plumes of water coming out of the cracks.” 

Outside of the prospect of water, researchers state there is an “orange gunk” on the surface, and they want to know what that could possibly be.

Sara Seager an astronomer from MIT in Cambridge, Mass., joined the panel this past Monday in Washington. She stated for years humanity has searched and wondered about finding alien life. Seager has been part of a search group called “Earth 2.0,” which seeks to find evidence of extraterrestrial life.

The search is on and NASA is happy to lead the way. Beyond Europa, researchers and scientists are monitoring and considering different resources to expand their search.

Extraterrestrial life has long been denied by Washington, as millions of “alien abduction” stories have piled up over the decades.

Are we alone? It is a question NASA is officially working on to solve.

NASA Thinks Alien Planet Could Soon Be Discovered Which Holds Life

Scientists at NASA believe that if everything goes according to plan, an alien planet very much like Earth could soon be discovered which holds life. So with that there has come a strong desire to find that planet and such an undertaking has been growing each year and it appears the interest is only getting stronger. NASA thinks the finding of such a world could easily happen within the next two decades.

At a NASA panel review where main attention was on the search for life in the cosmos, the deliberations focused on the questions whether Earth is alone or not in the Universe, along with the high-tech advances that have been made in the last 10 years that might permit scientists to come up with an answer to such questions.

Matt Mountain, who is the director of the Space Telescope Science Institute, spoke at the panel and explained about how it would be when the news broke that scientists had discovered Earth 2.0. He wanted people to imagine the moment when the entire globe woke up to the news that the Earth’s loneliness in space and time might have actually ended and it was possible that those on Earth might no longer be alone in space.

NASA seems to be very determined on discovering Earth 2.0, and with the brand new James Webb Space Telescope that is planned to launch into the cosmos in the year 2018, this is extremely possible. So within the next 20 years, it could happen that scientists might very well find one or more planets which are Earth-like and have on life on them somewhere out in the Universe.

At the present time, it is believed there are about 100 billion planets in the cosmos, and scientists think that quite a few of them could support some sort of life. The task that is facing NASA at the present time is finding out where such planets are located and then it would lead to the next undertaking, which would be producing the technology to get human beings there.

The search has brought scientists this far thanks in part to the Kepler space telescope. It was able to pinpoint numerous planets in its life span, even though it was unable to find any planets that were good enough to be considered to be just like Earth. The James Webb telescope is intended for that very purpose, since it will be placed about 930,000 miles away from the Earth which is around four times the expanse of the Earth from the Moon.

While the Webb telescope will have the capability to find Earth-like planets, it will not be able to tell if the planets are sheltering life on the exterior. The NASA scientists believe that if everything goes as they have planned, they actually think an alien planet very much like Earth could be discovered within the next two decades which holds life. So with that there has come a mission to find that planet and such an undertaking has seen growing amounts of attention with each year that passes.

By Kimberly Ruble

Sources:

The Huffington Post

Extreme Tech

Tech Times

Nasa Astronomer Kevin Hand: 'Extraterrestrial Life Can be Found on Jupiter's Moon Europa'

A Nasa scientist has said that we are close to finding extraterrestrial life in the universe.

Astronomer Kevin Hand has said that the Goldilocks Zone, the habitable band around a star that can support liquid water as it is neither too cold nor too hot, is likely to harbour intelligent life.

Scientists believe that tidal flexing, an effect of the tidal forces between an orbiting natural satellite, and geothermal energy expands this habitable area to include Jupiter's moon Europa.

Speaking at the Palaeontological Society of Southern Africa's 18th biennial conference, Hand said: "For the first time in our history we have the tools and technology to do this experiment and go out to these worlds.

Although Europa is covered in thick ice, its smooth surface had led scientists to believe that a water ocean exists beneath it, which could potentially hold extraterrestrial life.

Nasa is planning a mission to Europa in 2022 that will likely map the surface of the moon, but the mission to find life there might only begin in 2040.

The frozen shell of Europa also poses as difficulty, as the lander would have to drill through as much as 15km of ice to get to the ocean believed to be 100km deep.

"The submersibles we have today would do fine in exploring Europa, the only problem is getting them there," he said, as quoted by South Africa's Times Live.

There might be organisms around the ocean's hydrothermal vents, which emit geothermal heated water, such as microbial life or potentially more complex forms. There is a possibility of the existence of intelligent life.

Hand added that he is optimistic that in the near future, the agency will discover life somewhere in the universe.

"I think in the next 20 years we will find out if we are not alone in the universe," he said, adding that finding such life might be as simple as the Mars Rover discovering a fossil on the surface of the planet.

Meanwhile, speaking to BBC 5 Live, a professor of astronomy at the University of Nottingham said we were "pretty close" to finding life outside Earth.

Prof Michael Merrifield said observatories are making unprecedented discoveries about hundreds and potentially thousands of other worlds in our galaxy which could be inhabited.

NASA: We will find alien life within 20 years

Using new telescope technology, NASA scientists expect to confirm we're not alone in the Universe in the next 20 years. But they're not necessarily looking for E.T.

Dr. Matt Mountain is director of the Space Telescope Science Institute in Baltimore.

"We could be on the cusp of making such a great discovery that would change human history."

Dr. Mountain was one of the scientists who discussed the possibility this week at NASA's Washington headquarters.

"New technology and science are about to converge to a point when we can probably launch a telescope that can actually search the nearby stars for intelligent signs of life."

Dr. Mountain says one of his telescopes, the James Webb Space Telescope, will be launched in 2018. But he says what they find may be more like an amoeba rather than intelligent life.

"We don't know if we're going to find aliens walking around. We're looking for evidence of life in the atmospheres and we won't know whether there's just an amoeba or actually animals crawling around or in fact some sort of intelligent being."

Searching for Alien Life in the Universe? Don't Look for E.T

WASHINGTON — For the first time in history, humanity is within reach of finding Earth-like planets where life exists, but these extraterrestrials may not take the form of intelligent beings, experts say.

NASA's next-generation James Webb Space Telescope — set to launch in 2018 — and its larger successors will give scientists the opportunity to look for signatures of life in the atmospheres of planets outside the solar system, known as exoplanets. But these telescopes won't be capable of detecting whether the life forms are brainy beings or single-celled microbes.

"We believe we're very close to finding life on another planet," Sara Seager, an astronomer at MIT in Cambridge, Massachusetts, told a packed audience Monday (July 14) here at NASA Headquarters in Washington, D.C. Seager, who has been at the forefront of the search for a so-called "Earth 2.0," was part of a panel discussion about finding extraterrestrial life.

NASA's Kepler Space Telescope, which launched in 2009, has helped scientists discover thousands of exoplanets. Astronomers now know that basically every star in the Milky Way galaxy has at least one planet orbiting it, Seager said. And as many as one in five planets around sunlike stars may possess an Earth-like planet in the so-called habitable zone, orbiting just at the right distance from its parent star where liquid water — and therefore life — might exist.

John Mather, a Nobel laureate and astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, is also excited about the possibility of finding inhabited alien worlds. Mather is the project scientist for the James Webb Space Telescope (JWST), the $8.8 billion successor to the iconic Hubble Space Telescope.

Among other things, JWST will look for signs of life, or biosignatures — such as oxygen, carbon dioxide or water — in the atmospheres of exoplanets. The telescope will search for these biosignatures by analyzing the light that passes through the atmospheres of the planets as they orbit in front of their host stars.

But even with JWST, scientists would have to be "really lucky" to identify inhabited planets, because the light given off by these worlds is very faint, and the spacecraft can't collect enough light to see most of them, the panelists said. To really kick-start the search, NASA will need bigger telescopes, with mirrors that measure about 30 to 60 feet (10 to 20 meters) across — much larger than JWST's 21-foot (6.5 m) mirror, they said.

Still, if scientists find biosignatures in the atmosphere of an exoplanet, these clues will only tell them that some kind of life exists on the alien world — it won't tell them what form it takes, Seager said. For example, the extraterrestrial life could consist of simple bacteria or amoebas, instead of complex, multicellular beings.

JWST and its immediate successors won't be able to look for signals sent by intelligent life either, but if they find planets with any signs of life, other telescopes engaged in the Search for Extra-Terrestrial Intelligence (SETI) could focus on those planets and listen for radio waves or other signals that could point to a technologically advanced alien civilization. In fact, astronomers at the SETI Institute in Mountain View, California, are already making follow-up observations of exoplanets found by the Kepler spacecraft, Seager said.

Ultimately, humans may want to send probes or even manned spacecraft to planets that show signs of life — but with the limitations of current rocket technology, getting there would take much longer than a human lifetime.

By Tanya Lewis, Staff Writer

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