New Map of Big Bang Light Hints at Exotic Physics

Europe's Planck spacecraft has revealed the most detailed map yet of the earliest light in the universe, which reveals some tantalizing anomalies that could point toward new physics.

The new map tracks small temperature variations in the glow pervading space called the cosmic microwave background (CMB). This light was released just 380,000 years after the Big Bang, and contains a record of how our universe came to be.

By and large, the new data from Planck agree with cosmologists' leading ideas about how the universe formed. The theory of inflation suggests that after the Big Bang, the universe ballooned rapidly from its tiny, hot state, doubling in size every 10^-35 seconds (a decimal point followed by 34 zeroes and a one).

But where the basic models of inflation say this expansion should have happened uniformly in all directions, the new Planck results suggest that might not have been the case. [Universe's CMB Radiation Explained (Infographic)]

"One of the features of inflation is it says there should be no preferred direction — everywhere in the universe should be more or less the same," astrophysicist Marc Kamionkowski of Johns Hopkins University said today (March 21) during a NASA press call. "But when you look at the amplitudes, even by eye you can tell that one side of the universe looks different from the other side."

That is to say, the temperature variations in the CMB appear to be sized and spaced differently when Planck looks in one direction, than when it looks in the other.

There are other anomalies as well. The variations don't appear to behave the same on large scales as they do on small scales, and there are some particularly large features, such as a hefty cold spot, that were not predicted by basic inflation models.

Ultimately, the data show "some features that are surprising and very, very intriguing," said Charles Lawrence, U.S. Planck project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
"Hopefully in the process of understanding those features better we will be able to glimpse answers to some of our deepest questions."

Indeed, the map's deviations from what was predicted are not cause for disappointment among scientists, but rather exhilaration. They could even lead toward unraveling the mysteries of dark matter and dark energy, two perplexing constituents of the universe that have yet to be explained by mainstream theories.

For example, the new CMB measurements produce a new estimate for the age and expansion rate of the universe, which the Planck scientists calculate to be 13.8 billion years old, and 41.73 miles (67.15 kilometers) per second per megaparsec, respectively. The expansion rate is also known as the Hubble constant, and the new estimate is significantly lower than the values derived through other astronomical observations.

"This is one of the most exciting parts of the data, is this apparent tension between these different ways to estimate how rapidly the universe is expanding," said Martin White, U.S. Planck scientist at the University of California, Berkeley. "The hope would be that this is actually pointing toward some deficiency in the models or some extra physics."

The expansion rate of the universe is deeply connected to the idea of dark energy, which is the name scientists have given to whatever is causing the universe's expansion to accelerate. The finding could point toward a new direction of thinking about dark energy, including the possibility that it has changed over time.

"If it was different than the simplest models, if the amount of dark energy was somehow increasing with time in a given volume of space, then that would alleviate some of the tension," White said, and added, "that's a pretty radical thing to propose."

And getting to the bottom of the other anomalies in the Planck data may point to even more radical conclusions, such as the idea of multiple universes and bubble universes created by areas of the primordial universe that inflated at different rates.

It turns out that collisions between these bubbles of space-time are one possible explanation for why inflation might not have proceeded uniformly in all directions.

"The fact that these anomalies not only exist but exist on the very largest scales gives us some hope that we may be actually able to say something in the future about a multiverse," Kamionkowski said.

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Down with Light Pollution: Illinois Town Prizes Its Dark Side (SPACE.com)

A small town in Illinois has become the world's third International Dark Sky Community, a place that aims to protect the quality of its dark, star-filled sky by controlling the amount of outdoor lighting.

The town of Homer Glen was designated an International Dark Sky Community on Nov. 21. The town is located 30 miles (48 kilometers) southwest of Chicago, and residents there have worked hard to promote the dark sky movement by raising awareness about the negative effects of light pollution from wasteful outdoor lighting.

The International Dark-Sky Association is a U.S.-based non-profit organization that was founded in 1988 to champion the dark sky movement. A primary goal of the organization's International Dark Sky Places program is to preserve the quality of dark skies around the world, which are valuable assets to astronomers and skywatchers.

Homer Glen's proximity to Chicago prompted officials to start education campaigns for smart lighting policy. Excessive outdoor lighting can cause what is known as sky glow above the horizon, which can reduce the quality of astronomical observations.

A group of citizens from Homer Glen started an advocacy group called the Illinois Coalition for Responsible Outdoor Lighting. Their efforts resulted in the 2010 adoption of a statewide resolution condoning responsible outdoor lighting.

Local astronomy groups in Homer Glen also organize stargazing events twice a year for roughly 250 members of the public. [Telescopes for Beginners]

But the dark sky movement is about more than just astronomy. The initiative is aimed at raising awareness of other negative effects of light pollution, including energy, health and ecological concerns.

In a ceremony in 2008 hosted by the International Dark-Sky Association and the World Wildlife Fund (WWF), then-Lieutenant Governor of Illinois Pat Quinn praised Homer Glen for its "environmentally friendly" outdoor lighting policies and its promotion of Earth Hour, which is an annual global event organized by the WWF that encourages people to turn off lights and appliances for one hour to raise awareness about climate change.

"Homer Glen's dark sky ordinance conserves energy, protects wildlife, and reminds all of us of the natural beauty of a starry night," Quinn said in a statement.

Flagstaff, Ariz. was the first city to earn the International Dark Sky Community title, followed by Borrego Springs, Calif.

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Perseid Meteor Shower Light Show Peaks Tonight (SPACE.com)

In a double weekend treat, one of the most well-known and reliable meteor showers — the Perseid meteor shower — will reach its peak overnight Friday (Aug. 12) as the International Space Station flies across the sky above many U.S. cities.

The annual Perseid meteor shower returns this week, but is expected to hit its peak activity in the overnight hours of Friday and Saturday (Aug. 13). While the full moon of August may interfere with the meteor display, the best time to catch the pretty light show (weather permitting) is during the predawn hours, especially on Saturday morning, experts at NASA advise. 

And if you're looking skyward before dawn this week, you might also be able to glimpse the space station overhead. [Photos: Amazing Perseid Meteor Shower Displays]

The International Space Station will be making a series of early morning flybys over the U.S. throughout this week and into the weekend, NASA officials said. The massive orbiting complex shines bright enough that its visibility in the sky is not drowned out by moonlight or city lights.

NASA's space station tracker lists local flyby times, including those for several major cities such as Chicago, Dallas, Los Angeles and New York, that are expected to have good viewing opportunities on Friday and Saturday.

NASA is inviting the public to participate in a Perseids webchat and "all-night" meteor shower viewing party, hosted by astronomer Bill Cooke and his team from NASA's Marshall Space Flight Center in Huntsville, Ala. The webchat will begin at 11:00 p.m. EDT (0300 GMT) on Friday (Aug. 12) and will last until 5:00 a.m. EDT (0900 GMT) on Saturday (Aug. 13).

The Perseid meteor shower occurs every year as Earth passes through a stream of dust particles and debris from the Comet Swift-Tuttle. As these specks of comet dust hit the top of Earth's atmosphere at speeds of up to 140,000 miles per hour (225,000 kilometers per hour), they are heated and form bright meteor streaks that can be seen across the sky.

These meteors stream out of the constellation of Perseus, which is how the meteor shower got the name "Perseids." [Top 10 Perseid Meteor Shower Facts]

Skywatchers around the world are currently counting more than a dozen Perseids each hour, according to NASA and the International Meteor Organization. The light show should reach its peak between Aug. 12 and 13, as Earth orbits near the heart of the comet debris stream.

This year, however, the full moon occurs one hour after the peak of the Perseid meteor shower, which could outshine some of the fainter Perseids that would normally be visible against a darker sky, according to NASA. But before dawn, the full moon will be relatively low and the meteor count should be high at that time. [Video: Perseid Meteor Shower 2011 Guide]

The meteor shower will likely be viewed best under dark country skies, which will help eliminate light pollution.

Gaherty also reminds meteor watchers to have patience, as the streaks usually come in bunches, with wait times in between. He recommends budgeting at least an hour or two of skywatching to catch a good glimpse of this year's shower. 

Editor's note: If you snap an amazing photo of a Perseid meteor this year and would like to share it with SPACE.com for a possible story or gallery, please contact managing editor Tariq Malik at: tmalik@space.com.

You can follow SPACE.com staff writer Denise Chow on Twitter @denisechow. Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

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Climate scientists shine new light on methane mystery

Farmers work in a padi field at Khokana village, located south of Nepal's capital Kathmandu July 27, 2011.

Credit: Reuters/Navesh Chitrakar

By David Fogarty

SINGAPORE | Thu Aug 11, 2011 7:25am EDT

SINGAPORE (Reuters) - Atmospheric levels of methane, 20 times more powerful than carbon dioxide (CO2) at trapping heat, stayed steady for two decades to 2006 on wider fertilizer use to grow rice or a surge in natural gas demand, according to two separate studies in the journal Nature.

Climate researcher Fuu Ming Kai from the Massachusetts Institute of Technology's Singapore research center said in one study that methane output from rice fields in the Northern Hemisphere dropped during the period as fertilizers replaced manure and because of reduced water use.

In the second study, Murat Aydin at the University of California, Irvine, concluded that a drop in methane emissions from more efficient burning of fossil fuels and a surge in natural gas demand.

The studies aim to solve a puzzle that has confounded climate scientists for years: why did methane levels in the atmosphere, after rising steadily for many years, taper off in the mid-1980s in a dip lasting two decades?

Solving the puzzle is crucial because methane levels have risen more than 150 percent since the start of the industrial revolution, compared with CO2's 40 percent increase, and are on the rise again.

While the studies reach different conclusions, both studies point to human activities as the reason for the slowdown.

"In general most of the methane sources come from the Northern Hemisphere," Fuu told Reuters.

The main methane sources come from burning fossil fuels, rice paddies, coal mines, livestock and clearing and burning of tropical forests.

"We looked at the isotope data to see how it's changed over the past 20 to 30 years. And what we saw is a trend in the isotope signature and especially in the Northern Hemisphere."

Fuu said long-term data and comparing methane levels between the both hemispheres helped researchers conclude that about half the decrease in Northern Hemisphere methane emissions could be explained by reduced emissions from rice agriculture in Asia over the past three decades.

"It is important to know what the mechanism is behind the slow down. If you know this, you can adopt a suitable policy to reduce methane emissions," Fuu said.

Aydin concluded the drop coincided with rapid natural gas production as the fuel became increasingly price competitive with oil and other fossil fuel, instead of flaring it off. The gains came even though overall fossil fuel use increased as cleaner burning technologies helped keep methane emissions in check, he said.

"We speculate that the rising economic value of natural gas during the late 20th Century and the deployment of cleaner technologies led to sharp reductions in the release of light hydrocarbons into the atmosphere," the study says.

(Editing by Ed Lane)

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Thunder on Saturn Moon Could Shed Light on Lightning (SPACE.com)

Nola Taylor Redd, SPACE.com Contributor
Space.com Nola Taylor Redd, Space.com Contributor
space.com – Tue Jun 7, 10:14 am ET

Future missions to the Saturn moon Titan may look for lightning in a novel way — by searching for its rumbling companion, thunder.

Detecting thunder on the frigid, distant moon won't be as simple as pointing a microphone and reading the signal. Sound waves are shaped and altered by the material they travel through, and Titan's air is much different than Earth's.

To help identify any possible signals, two teams of scientists modeled what the sound wave for a thunderclap would look like where lightning touches down on Titan, and how it would shift after traveling through the moon's atmosphere. [Photos: The Rings and Moons of Saturn]

Different atmospheres make (different) waves

Nitrogen dominates the frosty air of Titan, the only moon in the solar system known to have a significant atmosphere. Methane clouds cross the planet, periodically raining liquid hydrocarbons onto the surface.

Many scientists hope that such storms bring with them lightning. The electrical discharge creates pockets of high temperatures that could allow the creation of complicated molecules. These, in turn, could have implications for the possibility of life on the moon.

The characteristics that make Titan's atmosphere so different from Earth also make it, from an acoustical standpoint, better.

"Sound carries farther on Titan than on Earth, or even Mars or Venus," Andri Petculescu, who worked on both of the recent studies, told SPACE.com.

Because of this, a detector could hear thunder rumble from relatively far away. But it would have to be created specifically for Titan.

"You can't bring any microphone off the shelf, designed for Earth, and assume it would work on Titan without modifications," Petculescu said. "Future missions would have microphones tailored for Titan's conditions."

Researchers would also have to keep in mind that lightning isn't the only possible source of loud noises on Titan. Petculescu pointed out that a meteorite hitting the surface or detonating in the air would boom loudly, much like thunder. The need to identify the distinguishing features of thunder is critical.

The two studies are part of a larger project to determine how thunder sounds on Titan, and to develop an accurate soundscape for the moon. Scientific documentaries, planetarium shows and even science fiction movies could utilize such a tool to accurately replicate the sounds heard by an astronaut standing on the surface of Titan, or various other planetary environments.

Petculescu described the various noises that could conceivably be heard on Titan, from the cascading of a methane creek to the rumble of thunder in the distance.

Scientists presented the two related projects at the May meeting of the Acoustical Society of America in Seattle..

Exploring Titan

Much of what scientists know about Titan comes from NASA's Cassini satellite, which studies the moon as part of its path around Saturn. In 2005, the Huygens probe, released from Cassini, took 2 1/2 hours to pass through the atmosphere and touch down on the surface of Titan.

The instruments on board Huygens were designed to study the surrounding atmosphere. The data was relayed from the probe to Cassini and back to Earth.

Because scientists knew about the potential for clouds — and thus lightning — Huygens was built with the idea that it might, in fact, be struck on the way in.

Neither Huygens nor Cassini (which is still sending information back to Earth) has detected lightning. However, NASA is presently exploring the possibility of another trip to the moon. The Titan Mare Explorer (TiME) is one of three missions considered for launch in 2016. If selected, it will attempt to land in and float on one of the large methane seas on the surface of Titan.

Unfortunately, the current proposal for TiME does not plan to include the equipment necessary to search for thunder. Studying the storms around the seas, however, will help scientists to understand more about how the weather cycle affects the moon.

The selection process will continue over the upcoming months, as teams continue to demonstrate progress.

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