The Raw Story

Tuesday, 13 January 2015

One of the Milky Way's arms might encircle the entire galaxy

Given that our Solar System sits inside the Milky Way Galaxy, getting a clear picture of what it looks like as a whole can be quite tricky. In fact, it was not until 1852 that astronomer Stephen Alexander first postulated that the galaxy was spiral in shape. And since that time, numerous discoveries have come along that have altered how we picture it.

For decades astronomers have thought the Milky Way consists of four arms - made up of stars and clouds of star-forming gas - that extend outwards in a spiral fashion. Then in 2008, data from the Spitzer Space Telescope seemed to indicate that our Milky Way has just two arms, but a larger central bar. But now, according to a team of astronomers from China, one of our galaxy's arms may stretch farther than previously thought, reaching all the way around the galaxy.

This arm is known as Scutum - Centaurus, which emanates from one end of the Milky Way bar, passes between us and Galactic Center, and extends to the other side of the galaxy. For many decades, it was believed that was where this arm terminated.

However, back in 2011, astronomers Thomas Dame and Patrick Thaddeus from the Harvard - Smithsonian Center for Astrophysics spotted what appeared to be an extension of this arm on the other side of the galaxy, placing it outside of our Solar System as well.

But according to astronomer Yan Sun and colleagues from the Purple Mountain Observatory in Nanjing, China, the Scutum - Centaurus Arm may extend even farther than that. Using a novel approach to study gas clouds located between 46,000 to 67,000 light-years beyond the center of our galaxy, they detected 48 new clouds of interstellar gas, as well as 24 previously-observed ones.

For the sake of their study, Sun and his colleagues relied on radio telescope data provided by the Milky Way Imaging Scroll Painting project, which scans interstellar dust clouds for radio waves emitted by carbon monoxide gas. Next to hydrogen, this gas is the most abundant element to be found in interstellar space - but is easier for radio telescopes to detect.

Combining this information with data obtained by the Canadian Galactic Plane Survey (which looks for hydrogen gas), they concluded that these 72 clouds line up along a spiral-arm segment that is 30,000 light-years in length. What's more, they claim in their report that: "The new arm appears to be the extension of the distant arm recently discovered by Dame & Thaddeus (2011) as well as the Scutum-Centaurus Arm into the outer second quadrant."

© Yan Sun/The Astrophysical Journal Letters, Vol. 798/Robert Hurt. NASA/JPL-Caltech/SSC

Illustration of our galaxy showing the possible extension of the Scutum-Centaurus Arm.

This would mean the arm is not only the single largest in our galaxy, but is also the only one to effectively reach 360° around the Milky Way. Such a find would be unprecedented given the fact that nothing of the sort has been observed with other spiral galaxies in our local universe.

Thomas Dame, one of the astronomers who discovered the possible extension of the Scutum-Centaurus Arm in 2011, was quoted by as saying: "It's rare. I bet that you would have to look through dozens of face-on spiral galaxy images to find one where you could convince yourself you could track one arm 360 degrees around."

Naturally, the prospect presents some problems. For one, there is an apparent gap between the segment that Dame and Thaddeus discovered in 2011 and the start of the one discovered by the Chinese team - a 40,000 light-year gap to be exact. This could mean that the clouds that Sun and his colleagues discovered may not be part of the Scutum-Centaurus Arm after all, but an entirely new spiral-arm segment.

If this is true, than it would mean that our Galaxy has several "outer" arm segments. On the other hand, additional research may close that gap (so to speak) and prove that the Milky Way is as beautiful when seen afar as any of the spirals we often observe from the comfort of our own Solar System.

Further Reading: arXiv Astrophysics,

Chomsky: We Are All – Fill in the Blank.

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Another minor earthquake has rattled eastern Connecticut.

Boston College's Weston Observatory says the 2.1 magnitude earthquake at about 7:30 a.m. Tuesday was in Plainfield. It was in the same area as five small earthquakes over five hours Monday morning.

The strongest of those was 3.1 magnitude and could be felt in Massachusetts and Rhode Island.

Last Thursday, an earthquake with a magnitude of 2.0 to 2.2 was felt in Plainfield. Homeowners reported it was strong enough to shake picture frames off the walls.

A research scientist at the Weston Observatory said such a series of small earthquakes in the Northeast is not unusual because the eastern U.S. is atop a tectonic plate affected by geological pressure.

One person is dead and dozens more are injured after smoke poured into one of Washington, D.C.'s busiest metro stations Monday, creating what authorities described as a "mass casualty" incident.

The heavy smoke began billowing out of L'Enfant Plaza Metro Station around 3 p.m. after a disabled train became trapped inside an underground tunnel, DC Fire and EMS reported.

At least 83 people were taken to area hospitals for treatment, including a firefighter, and two were critically injured, authorities said.

"We have one fatality, a woman who was in distress on the train, which I'm very sorry to report," Metro General Manager and CEO Richard Sarles said at a press briefing.

More than 200 people evacuated from the scene were evaluated for possible injuries, they stated.

"People could barely breathe," passenger Denzel Hatch told NBC Washington . "They had to evacuate us through the tunnel and walk back through the front. No electricity, no visibility, nothing. Couldn't see anything at first."

The source of the smoke has yet to be determined, according to the city's Metropolitan Area Transit Authority. They say they've activated the tunnel fans to ventilate the station which is located just blocks from the U.S. Capitol.

The National Transportation Safety Board is now handling the investigation, an WMATA spokeswoman told the Daily News.

D.C. Mayor Muriel Bowser offered her sentiments to the victims as well as her thanks to the "brave first responders" in a statement released later Monday night.

"We are all saddened by today's fatality aboard the Metrorail, and our thoughts and prayers go out to the family of the passenger who passed away," she stated. "I have been in contact with the WMATA leadership, and we will continue to keep the District's resources available in the aftermath of the incident."

'Mass Casualty' is a term utilized when additional resources are potentially necessary on large scale incidents," DC Fire Fighter L36 tweeted.

The station has since closed with Green Line services suspended between Navy Yard and Mt. Vernon Square and the Yellow Line services suspended between Pentagon City and Mt. Vernon Square.

Authorities say to expect "significant delays."

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Iranian President Hassan Rouhani said Tuesday that Iran can cope with the economic turmoil of falling oil prices, adding that Saudi Arabia and Kuwait will be harder hit.

Rouhani said that while oil now only accounts for one-third of Tehran's budget, some of the Gulf states are up to 95 percent reliant on it.

"If Iran suffers from the drop in oil prices, know that other oil-producing countries such as Saudi Arabia and Kuwait will suffer more than Iran," he said.

He added that "Kuwait's budget is 95 percent reliant on oil," and 90 percent of Saudi Arabia's "annual exports are related to oil."

Rouhani was addressing a crowd in the southern city of Bushehr - home to a nuclear power plant built with the help of the Russians, which became operational in 2011.

He also said that falling prices for crude oil are the result of "a plot that will be overcome with unity and resistance."

"Those [countries] who have planned the oil price reduction against some countries should know that they will regret it," he said, without elaborating on what countries he meant.

© AFP Photo / Atta Kenare

Iranian South Pars quarter one (SPQ1) gas platform in the Gulf near Qatar's territorial waters.

Rouhani was elected in 2013 on promises to turn around Iran's sanctions-hit economy. He has successfully lifted the country out of recession and recently began to stress the importance of non-oil exports.

Iran was somewhat caught off guard by the slide in oil prices, as its current budget was based on sales at US$100 a barrel.

Tehran cut that estimate to $72 in March but oil has now hit a six-year low, with Brent crude trading at just $46.

With Rouhani at the helm, inflation rates have halved to less than 20 percent. With progress in talks regarding Iran's controversial nuclear program, some sanctions by the West have been lifted.

But as oil prices continue to tumble, there is now the prospect of a deficit in Tehran, particularly as businesses are cut off from loans in the international banking system, as most of the sanctions still remain in place.

By seeking to hammer out a deal with the six world powers, Rouhani had hoped to breathe life into the Iranian economy by opening Iran up to foreign companies and partnership deals.

Due to Western sanctions, Iran's oil exports have dropped from 2.5 million barrels a day in 2011 to about one million barrels today, according to the US Energy Information Administration (EIA).

A new NASA satellite that will peer into the topmost layer of Earth's soils to measure the hidden waters that influence our weather and climate is in final preparations for a Jan. 29 dawn launch from California.

The Soil Moisture Active Passive (SMAP) mission will take the pulse of a key measure of our water planet: how freshwater cycles over Earth's land surfaces in the form of soil moisture. The mission will produce the most accurate, highest-resolution global maps ever obtained from space of the moisture present in the top 2 inches (5 centimeters) of Earth's soils. It also will detect and map whether the ground is frozen or thawed. This data will be used to enhance scientists' understanding of the processes that link Earth's water, energy and carbon cycles.

"With data from SMAP, scientists and decision makers around the world will be better equipped to understand how Earth works as a system and how soil moisture impacts a myriad of human activities, from floods and drought to weather and crop yield forecasts," said Christine Bonniksen, SMAP program executive with the Science Mission Directorate's Earth Science Division at NASA Headquarters in Washington. "SMAP's global soil moisture measurements will provide a new capability to improve our understanding of Earth's climate."

Globally, the volume of soil moisture varies between three and five percent in desert and arid regions, to between 40 and 50 percent in saturated soils. In general, the amount depends on such factors as precipitation patterns, topography, vegetation cover and soil composition. There are not enough sensors in the ground to map the variability in global soil moisture at the level of detail needed by scientists and decision makers. From space, SMAP will produce global maps with 6-mile (10-kilometer) resolution every two to three days.

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Researchers want to measure soil moisture and its freeze/thaw state better for numerous reasons. Plants and crops draw water from the soil through their roots to grow. If soil moisture is inadequate, plants fail to grow, which over time can lead to reduced crop yields. Also, energy from the sun evaporates moisture in the soil, thereby cooling surface temperatures and also increasing moisture in the atmosphere, allowing clouds and precipitation to form more readily. In this way, soil moisture has a significant effect on both short-term regional weather and longer-term global climate.

In summer, plants in Earth's northern boreal regions -- the forests found in Earth's high northern latitudes -- take in carbon dioxide from the air and use it to grow, but lay dormant during the winter freeze period. All other factors being equal, the longer the growing season, the more carbon plants take in and the more effective forests are in removing carbon dioxide from the air. Since the start of the growing season is marked by the thawing and refreezing of water in soils, mapping the freeze/thaw state of soils with SMAP will help scientists more accurately account for how much carbon plants are removing from the atmosphere each year. This information will lead to better estimates of the carbon budget in the atmosphere and, hence, better assessments of future global warming.

SMAP data will enhance our confidence in projections of how Earth's water cycle will respond to climate change.

"Assessing future changes in regional water availability is perhaps one of the greatest environmental challenges facing the world today," said Dara Entekhabi, SMAP science team leader at the Massachusetts Institute of Technology in Cambridge. "Today's computer models disagree on how the water cycle -- precipitation, clouds, evaporation, runoff, soil water availability -- will increase or decrease over time and in different regions as our world warms. SMAP's higher-resolution soil moisture data will improve the models used to make daily weather and longer-term climate predictions."

SMAP also will advance our ability to monitor droughts, predict floods and mitigate the related impacts of these extreme events. It will allow the monitoring of regional deficits in soil moisture and provide critical inputs into drought monitoring and early warning systems used by resource managers. The mission's high-resolution observations of soil moisture will improve flood warnings by providing information on ground saturation conditions before rainstorms.

SMAP's two advanced instruments work together to produce soil moisture maps. Its active radar works much like a flash camera, but instead of transmitting visible light, it transmits microwave pulses that pass through clouds and moderate vegetation cover to the ground and measures how much of that signal is reflected back. Its passive radiometer operates like a natural-light camera, capturing emitted microwave radiation without transmitting a pulse. Unlike traditional cameras, however, SMAP's images are in the microwave range of the electromagnetic spectrum, which is invisible to the naked eye. Microwave radiation is sensitive to how much moisture is contained in the soil.

The two instruments share a large, lightweight reflector antenna that will be unfurled in orbit like a blooming flower and then spin at about 14 revolutions per minute. The antenna will allow the instruments to collect data across a 621-mile (1,000-kilometer) swath, enabling global coverage every two to three days.

SMAP's radiometer measurements extend and expand on soil moisture measurements currently made by the European Space Agency's Soil Moisture Ocean Salinity (SMOS) mission, launched in 2009. With the addition of a radar instrument, SMAP's soil moisture measurements will be able to distinguish finer features on the ground.

SMAP will launch from Vandenberg Air Force Base on a United Launch Alliance Delta II rocket and maneuver into a 426-mile (685-kilometer) altitude, near-polar orbit that repeats exactly every eight days. The mission is designed to operate at least three years.

SMAP is managed for NASA's Science Mission Directorate in Washington by the agency's Jet Propulsion Laboratory (JPL) in Pasadena, California, with instrument hardware and science contributions made by NASA's Goddard Space Flight Center in Greenbelt, Maryland. JPL is responsible for project management, system engineering, radar instrumentation, mission operations and the ground data system. Goddard is responsible for the radiometer instrument. Both centers collaborate on science data processing and delivery to the Alaska Satellite Facility, in Fairbanks, and the National Snow and Ice Data Center, at the University of Colorado in Boulder, for public distribution and archiving. NASA's Launch Services Program at the agency's Kennedy Space Center in Florida is responsible for launch management. JPL is managed for NASA by the California Institute of Technology in Pasadena.

Eruptions of volcanoes like Tavurvur in Papa New Guinea in 2006 had a greater impact on the climate in the past 15 years than had previously been appreciated and may require climate models to be revised

Small volcanic eruptions over the past 20 years have been protecting the Earth from global warming, according to a new study.

Scientists have confirmed that droplets of sulphur-rich aerosols spewed into the upper atmosphere by volcanoes have been reflecting sunlight away from the Earth.

Until recently it was thought that only particularly large eruptions had any noticeable affect on the climate.

However, the new study has confirmed results from the end of last year that showed these small eruptions can have an accumulative impact on global temperature.

This could have helped decrease the global temperatures by between 0.05°C to 0.12°C over the past 15 years.

Since 1998, the warmest year on record, the steep increase in global temperatures seen during the 1990s has levelled off, failing to match computer model predictions for climate change.

This pause, or hiatus, has been blamed on weak solar activity and increased uptake of heat by the world's oceans.

This graph shows average land and ocean temperature anomalies between 1961 and 1990 around the world

The UN's Intergovernmental Panel on Climate Change last year concluded that the deep oceans had been responsible for absorbing an increasing amount of heat, but warned that this could not continue indefinitely.

However, in a paper published in November last year, atmospheric scientists at the Massachusetts Institute of Technology found that small volcanic eruptions in the early 21st century, which had been largely overlooked, were responsible for up to a third of the hiatus in warming.

Small eruptions from volcanoes like Japan's Mount Ontake throw sulphuric acid and aerosols into the air but many of these may have been accumulating unnoticed as a layer between the troposphere and stratosphere

Now researchers at the Lawrence Livermore National Laboratory, in California, have found signs of the effects from eruptions from the late 20th century and early 21st century in the atmospheric temperature, moisture and amount of sunlight reflected from the atmosphere.

They also found that the eruption of Pinatubo, a volcano on the island of Luzon in the Philippines, which last erupted in 1991, also caused a drop in tropical rainfall.

'The fact that these volcanic signatures are apparent in multiple independently measured climate variables really supports the idea that they are influencing climate in spite of their moderate size,' said Mark Zelinka, a climate scientist at Lawrence Livermore and one of the authors of the new study.

The apparent mismatch between observed temperature increases and predictions from climate change models has led to some to claim that global warming has stalled, as seen by the black line in the graph above

'If we wish to accurately simulate recent climate change in models, we cannot neglect the ability of these smaller eruptions to reflect sunlight away from Earth.'

The findings confirm the work of Dr David Ridley, a climate scientist at MIT who was the lead author on the November study on volcanos.

He found that droplets of sulphuric acid and aerosols were accumulating at the intersection between the stratosphere and troposphere layers of the atmosphere.

Using ground, air and space based instruments, Dr Ridley and his colleagues were able to get a better estimate of the aerosols accumulating in these layers, around six to nine miles above the Earth's surface.

Globally, there are thousands of volcanoes, like this one in Russia, throwing aerosols into the atmosphere

Previously they had been missed as most satellite measurements of volcanic aerosols are restricted to the parts of the stratosphere higher than nine miles as cloud cover can interfere with measurements below that.

This means, particularly around the poles where the stratosphere extends down to six miles above the surface, a significant chunk of volcanic aerosols were being missed.

He estimated that that since 2000 volcanoes may have caused cooling of between 0.05 degrees C and 0.12 degrees C.

Dr Benjamin Santer, who led the new study, said: 'This new work shows that the climate signals of late 20th- and early 21st-century volcanic activity can be detected in a variety of different observational data sets.'

Professor Ross McKitrick, an environmental economist from the University of Guelph in Canada, said the results could mean that climate models that are used to inform policy decisions are inaccurate.

If volcanic eruptions are masking some of the impacts of greenhouse gases like carbon dioxide, then the climate may be more sensitive than previously thought, or changes in aerosols could be responsible for some of the temperature changes attributed to carbon dioxide.

He said: 'If small variations in volcanic activity turn out to have larger and more persistent climatic effects than previously thought, this should have important implications for how climate models are parameterized and how greenhouse gas attribution studies are done.

'The study seems to me to raise the possibility that commonly-used historical reconstructions of volcanic dust forcing may not have been all that reliable.

'Climate modelers rely on dust veil indexes that use measures of known historical volcanic activity to estimate optical effects in the atmosphere.

'These are then used to estimate natural forcings over the 20th century, which are then used in greenhouse gas signal detection (attribution) studies.

'If the historical reconstructions weren't capturing the full magnitude of volcanic effects on the climate, as this study suggests, that presumably means those attribution studies need re-examination as well.'

Iranian hard-liners are lashing out at Saudi Arabia, accusing it of conspiring with the West to keep oil prices low in a bid to harm the Islamic Republic's economy and pressure the country to conclude a nuclear deal with West. In retaliation, Iranian hawks are urging restive Shia Muslims in eastern Saudi Arabia to rebel against the ruling House of Saud.

Iranian hawks' accusations have mounted over the Saudi's refusal to cut production - in an effort to maintain its share of the global oil market - fueling the precipitous slide in prices. Crude oil prices have fallen by more than half since June, from $115 a barrel to below $50.

"We will not forget which countries schemed to lower the price of oil," the speaker of Iran's parliament, Ali Larijani warned darkly during a visit last month to Damascus, the Syrian capital.

U.S. officials deny any collusion between Washington and Riyadh.

"The Saudis learned their lesson from the past when they curbed production to help keep oil prices high, only to see Russia and Venezuela grab some of their market share," said a senior U.S. State Department official, who declined to be named.

The real targets of Saudi Arabia's decision not to cut production and to contribute to the falling price of oil are America's shale oil producers, the official argued.

American oil production

Thanks to shale oil, America has become the world's largest oil producer, an emergence that has reshaped the world's energy market.

Though America does not export crude oil, it imports much less now, increasing reserves around the world. Global demand for oil has fallen with the downturn in global economic activity and with increased efficiency. And consumers' switch from oil to other fuels and energy sources, including renewable energy, is helping reshape oil markets, experts say.

American shale oil producers have been hard hit by the slumping price of crude.

Prices started to tumble when the Saudi-dominated Organization of Petroleum Exporting Countries (OPEC), which controls about 40 percent of the world market, failed to decide on production curbs during a November meeting in Vienna.

Charges of price manipulation

Like Iran, whose government depends heavily on oil revenues, other economically hard-pressed exporters such as Russia, Nigeria and Venezuela have accused Saudi Arabia of manipulating oil prices for political purposes.

Kremlin aides have decried low oil prices as part of an anti-Russian plot hatched by the United States and Saudi Arabia to push their country toward collapse.

But the loudest conspiracy accusations come from Tehran.

The weekly newsletter affiliated with Iran's Islamic Revolutionary Guards Corps (IRGC), the elite military group that protects Iran's theocratic Shia Muslim regime, last month threatened revenge on the Sunni-ruled Gulf kingdom "with all the means Iran has at its disposal," Memri TV recently reported. It's part of the Middle East Media Research Institute, a U.S.-based nonprofit that monitors Mideast media.

Memri also reported that Amir Mousavi, a former IRGC diplomat and director of Iran's Center for Strategic and International Studies, recently warned, "Saudi Arabia's move is a suicidal step in the struggle against Iran in the region."

"So far, Tehran has held back and has acted in moderation," Mousavi continued. "... Saudi Arabia is certain that Iran will not respond easily, but it seems that this time the situation is different, and if necessary Saudi Arabia's economic interests in the region and in the world will be harmed."

Retaliatory measures

Some anti-Saudi Iranians already appear to be retaliating, urging disaffected Shiites in eastern Saudi Arabia to rebel. An IRGC-affiliated Twitter account on December 20 posted, "People must defend themselves against the repeated military attacks by the Al-Saud regime."

Iranian threats toward U.S. ally Saudi Arabia are nothing new. But with the region roiled by vicious sectarian struggles, the war of words risks pouring fuel - cut rate or not - on Shia-Sunni fires.

Tehran's tougher language is at odds with U.S. President Barack Obama's conciliatory comments about Iran. Last week, in an interview with , he said Iran has an opportunity via talks about a nuclear deal "to get right with the world." He held out the possibility of opening a U.S. embassy in Tehran and offered the prospect of Iran being accepted as a "successful regional power."

Nuclear talks resuming

Nuclear talks are set to resume next week in Geneva between Iran and the P5 + 1 - the United States, China, France, Russia and the United Kingdom, plus Germany. Western governments have long feared Iran has been developing a nuclear program to build weapons; Tehran insists the country needs nuclear power for energy purposes.

In November 2013, Iran made a one-year deal with world powers to freeze its nuclear program in exchange for easing international sanctions against the country. The deal since has been extended until July.

At a conference Sunday in Tehran, Iranian President Hassan Rouhani said the country needs to end its political isolation so its economy can grow. The moderate-inclined Iranian president has been criticized by Iranian hard-liners for his determination to seal a nuclear deal. Iranian hawks are wary of any compromising with the West.

The Raw Story

Focused on providing independent journalism.

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Tuesday, 13 January 2015

One of the Milky Way's arms might encircle the entire galaxy

6th earthquake in 2 days rattles Connecticut

Mysterious smoke that filled DC train station leaves one person dead and over 80 hospitalized

Rouhani: Iran will weather oil price slide, some Gulf states will suffer

NASA: Satellite to get the dirt on soil moisture

Volcano eruptions found to have cooled global temperatures since 2000

Iran accuses Saudis of oil conspiracy

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