Today at New Scientist: 21 January 2013

Twitter reveals how Higgs gossip reached fever pitch

Anyone who fondly remembers the heady days of excitement preceding the Higgs boson announcement last year can now relive the experience

Vibrating navigator shows cyclists the way

A buzzing GPS-fuelled belt that tells cyclists when to turn might help them keep their eyes on the road and save lives

Call off the pregnancy police - women want the truth

Pregnant women can do without being made to feel guilty and burdened by wrong or contradictory advice. Just give them the facts, says Linda Geddes

Supernova-powered bow shock creates cosmic spectacle

The infrared vision of NASA's Spitzer Space Telescope shows how a massive speeding star is electrifying its surroundings

First video of squid sex reveals deep-sea Kama Sutra

Watch a pair of squid caught in the act for the first time in an unexpected sexual position

Let's be clear on health risks from radiation

Should Californians have had iodine after Fukushima? In Radiation Robert Peter Gale and Eric Lax clear up the confusion over radiation and health

Wind power delivers too much to ignore

Although aesthetic concerns need to be heard, qualms about wind's reliability are wide of the mark, argues an energy policy researcher

Quadruple DNA helix discovered in human cells

The classic double helix has been joined by a four-stranded version that may play a role in cancer

Turn up the bass to scare birds away from planes

Subwoofers that blast out sounds too low to be heard by humans can keep birds out of busy air space, and prevent them colliding with planes

Earth may be crashing through dark matter walls

If the universe is a patchwork quilt of exotic force fields, we should be able to detect dark matter whenever we cross between patches

Blinded by sun? Let your steering wheel guide you

A steering wheel that buzzes when drivers are dazzled by bright lights and drift from their lane could help curb accidents

NASA planet-hunter is injured and resting

The Kepler space telescope has put its search for alien Earths on hold while it recovers from a stressed reaction wheel

High-tech Dreamliner's wings clipped by battery trouble

Boeing's 787 Dreamliner is replete with cutting-edge technology. But problems with its complex systems now have the planes grounded around the world

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India, Australia to start nuclear energy talks

NEW DELHI: India and Australia plan to begin civil nuclear cooperation talks in March after Canberra agreed last year to open negotiations to export uranium fuel to the energy-hungry South Asian nation.

The two countries will hold the first round of talks in the Indian capital, Indian foreign minister Salman Khurshid said in a statement.

"We shall be commencing negotiations on a Civil Nuclear Energy Cooperation Agreement in March," Khurshid said after discussions with his Australian counterpart, Bob Carr, in the Indian capital.

Australia had earlier refused to sell uranium to India as it has not signed the Nuclear Non-Proliferation Treaty but reversed its stand last October as it sought to improve ties with one of Asia's third biggest economy.

"India is a key part of Australia's future," Carr said.

The two countries have said the formal negotiations could last up to two years.

New Delhi -- backed by the United States -- won a special exemption in 2008 from the Nuclear Suppliers Group (NSG), which governs global nuclear trade, to allow it to buy reactors and fuel from overseas.

India, which has tense relations with its nuclear-armed neighbour Pakistan, had been subject to a global embargo since the 1970s when it first conducted a nuclear weapons test.

New Delhi has sought to forge close ties with a host of countries with deposits of uranium, including Mongolia, Tajikistan and Canada.

India is heavily dependent on coal and produces less than three percent of its energy from its existing atomic plants. The government hopes to raise the figure to 25 percent by 2050.

Although Australia does not use nuclear power itself, it is the world's third-ranking uranium producer and holds an estimated 23 percent of the world's reserves.

-AFP/ac

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Bad parking job? Text the driver through the license plate

Be a good samaritan and warn a car owner.

(Credit:
Screenshot by Amanda Kooser/CNET)

Trying to find parking in San Francisco sometimes feels likes a car-based version of "Survivor." It's not pretty. Cars block driveways, drivers forget to curb their wheels, lights get left on, and meters run out. These are all reasons why you might want to contact a vehicle's owner. If everyone in San Francisco signed up for CurbTXT, then it would be easy to get in touch.

Drivers can sign up for CurbTXT by registering their license plates and phone numbers. A sticker on the
car gives people an anonymous way to contact the driver through text messaging by referencing the plate number. The service forwards the message to the owner.

CurbTXT is a sweet idea. It could turn San Francisco into a wonderland of parking good deeds, helping people avoid fines and giving them the opportunity to move their vehicles before they get towed.

CurbTXT faces an uphill battle as far as adoption. It also opens up the possibility of prank texts like "OMG your car is full of monkeys!!!" To combat that, users can report inappropriate messages and abusers will be blocked.

According to the Evernote blog, dozens of texts have been sent through the service since it launched last fall. That's not much, but CurbTXT founders have chatted with people from the San Francisco board of supervisors about getting city support for the project. Until then, the service is getting users through flyers and word-of-mouth.

(Via Opportunity Notes)

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Attack at Algeria Gas Plant Heralds New Risks for Energy Development

The siege by Islamic militants at a remote Sahara desert natural gas plant in Algeria this week signaled heightened dangers in the region for international oil companies, at a time when they have been expanding operations in Africa as one of the world's last energy frontiers. (See related story: "Pictures: Four New Offshore Drilling Frontiers.")

As BP, Norway's Statoil, Italy's Eni, and other companies evacuated personnel from Algeria, it was not immediately clear how widely the peril would spread in the wake of the hostage-taking at the sprawling In Amenas gas complex near the Libyan border.

Map by National Geographic

Algeria, the fourth-largest crude oil producer on the continent and a major exporter of natural gas and refined fuels, may not have been viewed as the most hospitable climate for foreign energy companies, but that was due to unfavorable financial terms, bureaucracy, and corruption. The energy facilities themselves appeared to be safe, with multiple layers of security provided both by the companies and by government forces, several experts said. (See related photos: "Oil States: Are They Stable? Why It Matters.")

"It is particularly striking not only because it hasn't happened before, but because it happened in Algeria, one of the stronger states in the region," says Hanan Amin-Salem, a senior manager at the industry consulting firm PFC Energy, who specializes in country risk. She noted that in the long civil war that gripped the country throughout the 1990s, there had never been an attack on Algeria's energy complex. But now, hazard has spread from weak surrounding states, as the assault on In Amenas was carried out in an apparent retaliation for a move by French forces against the Islamists who had taken over Timbuktu and other towns in neighboring Mali. (See related story: "Timbuktu Falls.")

"What you're really seeing is an intensification of the fundamental problem of weak states, and empowerment of heavily armed groups that are really well motivated and want to pursue a set of aims," said Amin-Salem. In PFC Energy's view, she says, risk has increased in Mauritania, Chad, and Niger—indeed, throughout Sahel, the belt that bisects North Africa, separating the Sahara in the north from the tropical forests further south.

On Thursday, the London-based corporate consulting firm Exclusive Analysis, which was recently acquired by the global consultancy IHS, sent an alert to clients warning that oil and gas facilities near the Libyan and Mauritanian borders and in Mauritania's Hodh Ech Chargui province were at "high risk" of attack by jihadis.

"A Hot Place to Drill"

The attack at In Amenas comes at a time of unprecedented growth for the oil industry in Africa. (See related gallery: "Pictures: The Year's Most Overlooked Energy Stories.") Forecasters expect that oil output throughout Africa will double by 2025, says Amy Myers Jaffe, executive director of the energy and sustainability program at the University of California, Davis, who has counted 20 rounds of bidding for new exploration at sites in Africa's six largest oil-producing states.

Oil and natural gas are a large part of the Algerian economy, accounting for 60 percent of government budget revenues, more than a third of GDP and more than 97 percent of its export earnings. But the nation's resources are seen as largely undeveloped, and Algeria has tried to attract new investment. Over the past year, the government has sought to reform the law to boost foreign companies' interests in their investments, although those efforts have foundered.

Technology has been one of the factors driving the opening up of Africa to deeper energy exploration. Offshore and deepwater drilling success in the Gulf of Mexico and Brazil led to prospecting now under way offshore in Ghana, Mozambique, and elsewhere. (See related story: "New Oil—And a Huge Challenge—for Ghana.") Jaffe says the Houston-based company Anadarko Petroleum has sought to transfer its success in "subsalt seismic" exploration technology, surveying reserves hidden beneath the hard salt layer at the bottom of the sea, to the equally challenging seismic exploration beneath the sands of the Sahara in Algeria, where it now has three oil and gas operations.

Africa also is seen as one of the few remaining oil-rich regions of the world where foreign oil companies can obtain production-sharing agreements with governments, contracts that allow them a share of the revenue from the barrels they produce, instead of more limited service contracts for work performed.

"You now have the technology to tap the resources more effectively, and the fiscal terms are going to be more attractive than elsewhere—you put these things together and it's been a hot place to drill," says Jaffe, who doesn't see the energy industry's interest in Africa waning, despite the increased terrorism risk. "What I think will happen in some of these countries is that the companies are going to reveal new securities systems and procedures they have to keep workers safe," she says. "I don't think they will abandon these countries."

This story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge.

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President Obama Calls for 'Collective Action'

Invoking the nation's founding values, President Obama marked the start of his second term today with a sweeping call for "collective action" to confront the economic and social challenges of America's present and future.

"That is our generation's task, to make these words, these rights, these values -- of life, and liberty, and the pursuit of happiness -- real for every American," Obama said in an inaugural address delivered from the west front of the U.S. Capitol.

"Being true to our founding documents does not require us to agree on every contour of life; it does not mean we will all define liberty in exactly the same way, or follow the same precise path to happiness. Progress does not compel us to settle centuries-long debates about the role of government for all time," he said, giving nod to the yawning partisan divide.

"But it does require us to act in our time."

The call to action, on the eve of what's shaping up to be another contentious term with Republicans and Congress, aimed to reset the tone of debate in Washington and turn the page on the political battles of the past.

"For now decisions are upon us, and we cannot afford delay. We cannot mistake absolutism for principle, or substitute spectacle for politics, or treat name-calling as reasoned debate," Obama said. "We must act, knowing that our work will be imperfect."

Pablo Martinez Monsivais/AP Photo

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The address, lasting a little less than 20 minutes, laid out in broad terms Obama's vision for the next four years, alluding to looming policy debates on the war in Afghanistan, deficit reduction, immigration, and overhaul of Social Security and Medicare.

Obama also became the first president, at least in recent inaugural history, to make explicit mention of equality for gay and lesbian Americans. He made repeated mentions of "climate change," something no president has said from such a platform before.

The president stuck closely to his campaign themes, offering few new details of his policy proposals, however. Those are expected to come next month in the State of the Union address Feb. 12.

"A decade of war is now ending. An economic recovery has begun. America's possibilities are limitless, for we possess all the qualities that this world without boundaries demands: youth and drive; diversity and openness; an endless capacity for risk and a gift for reinvention," Obama said, sounding optimistic tones.

"We are made for this moment, and we will seize it," he said, "so long as we seize it together."

Hundreds of thousands packed the National Mall in chilly 40-degree temperatures and brisk wind to hear Obama's remarks and witness the ceremonial swearing-in. While the crowds were smaller than four years ago, the U.S. Park Police said the Mall reached capacity and was closed shortly before Obama took the podium.

Shortly before the address, Obama placed his left hand on the stacked personal Bibles belonging to President Abraham Lincoln and Dr. Martin Luther King Jr., and raised his right to repeat the oath administered by Supreme Court Chief Justice John Roberts.

"I, Barack Hussein Obama, do solemnly swear that I will faithfully execute the office of president of the United States," he said, "and will to the best of my ability, preserve, protect and defend the Constitution of the United States."

Obama and Biden were both officially sworn in during private ceremonies Sunday, Jan. 20, the date mandated by the Constitution for presidents to begin their terms.

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Quadruple DNA helix discovered in human cells

Sixty years after James Watson and Francis Crick established that DNA forms a double helix, a quadruple-stranded DNA helix has turned up.

Quadruple helices that intertwine four, rather than two, DNA strands had been made in the laboratory, but were regarded as curiosities as there was no evidence that they existed in nature. Now, they have been identified in a range of human cancer cells.

The four-stranded packages of DNA, dubbed G-quadruplexes, are formed by the interaction of four guanine bases that together form a square. They appear to be transitory structures, and were most abundant when cells were poised to divide. They appeared in the core of chromosomes and also in telomeres, the caps on the tips of chromosomes that protect them from damage.

Because cancer cells divide so rapidly, and often have defects in their telomeres, the quadruple helix might be a feature unique to cancer cells. If so, any treatments that target them will not harm healthy cells.

"I hope our discovery challenges the dogma that we really understand DNA structure because Watson and Crick solved it in 1953," says Shankar Balasubramanian of the University of Cambridge, UK.

Tagged with antibodies

Balasubramanian's team identified the four-stranded structures in cancer cells with the help of an antibody that attaches exclusively to G-quadruplexes. To stop them from unravelling into the ordinary DNA, they exposed the cells to pyridostatin, a molecule that traps quadruple helices wherever they form.

This enabled the researchers to count how many formed at each stage of cell multiplication. The G-quadruplexes were most abundant in the "S-phase" – when cells replicate their DNA just prior to dividing.

"I expect they will also exist in normal cells, but I predict that there will be differences with cancer cells," says Balasubramanian. His hunch is that the G-quadruplexes are triggered into action by chaotic genomic mutations and reorganisations typical of cancerous or precancerous cells.

"This research further highlights the potential for exploiting these unusual DNA structures to beat cancer, and the next part of this is to figure out how to target them in tumour cells," says Julie Sharp of Cancer Research UK, which funded the research.

Another important question that Balasubramanian's and other teams will try to answer is whether G-quadruplexes play a role in embryo development, and whether such a role is mistakenly reactivated in cancer cells. "We plan to find out whether the quaduplexes are a natural nuisance, or there by design," he says.

Journal reference: Nature Chemistry, DOI: 10.1038/NCHEM.1548

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Football: Dempsey late show gives United frostbite

LONDON: A stoppage-time goal by Clint Dempsey saw Tottenham Hotspur snatch a 1-1 draw at home to Manchester United on Sunday that prevented the Premier League leaders from restoring their seven-point lead.

United had taken the lead through Robin van Persie in the 25th minute and looked set to hold on for a narrow victory until Dempsey scrambled the ball home from close range in injury time at a snow-sprinkled White Hart Lane.

The result means that second-place Manchester City are now five points behind United, while Spurs finish the weekend trailing third-place Chelsea by four points and leading Everton by the same distance.

It was only the fifth time this season that Alex Ferguson's side have failed to take maximum points from a league game and they have taken just a point from Spurs, who prevailed 3-2 at Old Trafford in September.

Persistent snowfall in north London had put the fixture in jeopardy, but the game survived a pitch inspection 70 minutes prior to kick-off and as the game got under way, the snow had started to ease.

Spurs looked to take the initiative, Dempsey seeing a volley blocked by Nemanja Vidic and the recalled Scott Parker shooting over from 22 yards, but United threatened first when van Persie headed straight at Hugo Lloris.

Few players have caused Patrice Evra problems as consistently as Aaron Lennon in recent seasons and the Spurs winger left the Frenchman trailing in the 14th minute before drawing a save from De Gea with a low shot.

United started the game with Wayne Rooney on the bench but there is always danger when van Persie is around and in the 25th minute the Dutchman struck for the 10th time in as many league games to put the visitors ahead.

Danny Welbeck drifted in from the left before spraying the ball wide to England colleague Tom Cleverley, and his curling cross was headed in at the back post by the leaping van Persie.

Spurs resumed their assault on the United goal but both Jermain Defoe and Gareth Bale were thwarted by agile saves from De Gea, who readjusted well to block the Welshman's deflected shot shortly before half-time.

Defoe shot wide early in the second period, before Bale shaped a beautiful effort with the outside of his left foot that drifted over.

De Gea then produced an incredible reaction save with his legs to thwart Dempsey, who was able to take aim at an exposed goal from just eight yards after a slalom into the box by Mousa Dembele.

United manager Ferguson introduced Rooney with half an hour remaining and he immediately had a penalty appeal rejected after being caught by Steven Caulker just inside the Tottenham area.

Spurs resumed their pressure, De Gea saving at his near post from Dempsey, before Welbeck narrowly failed to convert a low cross from Rafael at the other end.

A clear sight of goal arrived for the hosts in the 78th minute, but when Lennon sent Defoe clear, his former West Ham United team-mate Rio Ferdinand slid in from nowhere to prevent an equaliser with a vital block.

Ferdinand then produced a telling intervention with five minutes left, bravely getting his head to a fierce Bale strike to divert the ball narrowly wide of the left-hand post.

It seemed Spurs were destined to leave empty-handed, but with the final whistle beckoning, Dempsey thrashed a loose ball into the bottom-left corner to give United's pursuers a glimmer of hope in the title race.

-AFP/ac

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Is your landlord after your electronics?

But what if you use it in the corridor?

(Credit:
Jason Cipriani/CNET)

Sometimes, readers send me things to incite an emotion or two.

Sometimes it's laughter. Sometimes it's nausea. Sometimes, though, it's mere bafflement.

An example of this last one came from a reader in Houston. She sent me a lease agreement created by a company called Fine Arts Apartments.

She asked me to focus on one particular clause: "No use of electronics in common areas."

This seemed so peculiarly draconian that I wondered how it might have come about.

Did it really mean that you couldn't walk along the corridors of one of Fine Arts Apartments' buildings listening to Beethoven or Nirvana on your
iPod? Did it mean you couldn't take pictures of its no doubt pristine paintwork with your Samsung Galaxy S3?

Then I wondered about what sort of mind might have written these words, which appear to threaten that if you so much as whip your
iPad out in common parts, you could be breaking the terms of your lease.

Reaching bravely for my electronics, I contacted Arne Haarhaus, who represents the management of Fine Arts Apartments.

I wondered what he had against electronics. I wondered what would happen if there had been an emergency and someone had whipped out their cell phone to, for example, warn of a hirsute intruder in the building.

Haarhaus insisted that of course he wasn't part of some movement that wished to take us back to the times when we communicated via stone
tablets, rather than silver ones.

He's keen on beginning his sentences with the phrase "of course."

"Of course everyone can use any device in an emergency," he wrote in an e-mail. "Of course everyone with any special needs can use what she or he needs to use."

The intention of the clause was merely to keep the noise down in the building, he said. This is commendable. Of course.

He continued: "Since we had some experience with friends of tenants who walk up and down the bedroom window of a neighbor, we decided to write something like this and explain it at every lease signing -- everyone who signed a lease like this knows what the intent is."

But Mr. Haarhaus, my lawyer always tells me that when words are written down clearly, they mean what they say. And this lease also appeared to include the threat of a three-day notice of eviction for transgression.

Haarhaus continued: "No one ever had been evicted about anything like this, and would not."

More Technically Incorrect

But my lawyer would say the terms of the lease are clear. Why wouldn't people be evicted if they break the terms?

"Because we do not know if it was an emergency or not," he replied.

Indeed. So while no one enjoys noise from others keeping them up at night, why bother to have such a clause?

It wasn't my intention to harass Haarhaus. It just seemed such an odd thing to have written. He assured me that this wasn't any sort of anti-gadget crusade.

Shortly afterward, however, I received another e-mail from him.

"Probably you heard about the dogs," he wrote. "We have told everyone with this terms (sic) that we do not allow dogs at anytime."

The dogs? Wait, what does this have to do with the electronics clause?

"This was part of 3-day notices in the past," he continued.

Ah, so he enforces some clauses, but not the gadget clause? I was becoming confused.

As if returning to the principle of gadgets and emergencies, he added: "Of course we do allow medical dogs."

Even if they make a noise, it seems.

I am sure that Fine Arts Apartments' units suit many people. Those who comment on Yelp seem reasonably divided about how fine they are. One might expect that.

But I haven't heard of a clause in a lease agreement that baldly bans the use of all electronics in the common areas. Perhaps readers have.

"Maybe we should use a different text; we will review this wording," Haarhaus finally conceded.

Maybe.

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Attack at Algeria Gas Plant Heralds New Risks for Energy Development

The siege by Islamic militants at a remote Sahara desert natural gas plant in Algeria this week signaled heightened dangers in the region for international oil companies, at a time when they have been expanding operations in Africa as one of the world's last energy frontiers. (See related story: "Pictures: Four New Offshore Drilling Frontiers.")

As BP, Norway's Statoil, Italy's Eni, and other companies evacuated personnel from Algeria, it was not immediately clear how widely the peril would spread in the wake of the hostage-taking at the sprawling In Amenas gas complex near the Libyan border.

Map by National Geographic

Algeria, the fourth-largest crude oil producer on the continent and a major exporter of natural gas and refined fuels, may not have been viewed as the most hospitable climate for foreign energy companies, but that was due to unfavorable financial terms, bureaucracy, and corruption. The energy facilities themselves appeared to be safe, with multiple layers of security provided both by the companies and by government forces, several experts said. (See related photos: "Oil States: Are They Stable? Why It Matters.")

"It is particularly striking not only because it hasn't happened before, but because it happened in Algeria, one of the stronger states in the region," says Hanan Amin-Salem, a senior manager at the industry consulting firm PFC Energy, who specializes in country risk. She noted that in the long civil war that gripped the country throughout the 1990s, there had never been an attack on Algeria's energy complex. But now, hazard has spread from weak surrounding states, as the assault on In Amenas was carried out in an apparent retaliation for a move by French forces against the Islamists who had taken over Timbuktu and other towns in neighboring Mali. (See related story: "Timbuktu Falls.")

"What you're really seeing is an intensification of the fundamental problem of weak states, and empowerment of heavily armed groups that are really well motivated and want to pursue a set of aims," said Amin-Salem. In PFC Energy's view, she says, risk has increased in Mauritania, Chad, and Niger—indeed, throughout Sahel, the belt that bisects North Africa, separating the Sahara in the north from the tropical forests further south.

On Thursday, the London-based corporate consulting firm Exclusive Analysis, which was recently acquired by the global consultancy IHS, sent an alert to clients warning that oil and gas facilities near the Libyan and Mauritanian borders and in Mauritania's Hodh Ech Chargui province were at "high risk" of attack by jihadis.

"A Hot Place to Drill"

The attack at In Amenas comes at a time of unprecedented growth for the oil industry in Africa. (See related gallery: "Pictures: The Year's Most Overlooked Energy Stories.") Forecasters expect that oil output throughout Africa will double by 2025, says Amy Myers Jaffe, executive director of the energy and sustainability program at the University of California, Davis, who has counted 20 rounds of bidding for new exploration at sites in Africa's six largest oil-producing states.

Oil and natural gas are a large part of the Algerian economy, accounting for 60 percent of government budget revenues, more than a third of GDP and more than 97 percent of its export earnings. But the nation's resources are seen as largely undeveloped, and Algeria has tried to attract new investment. Over the past year, the government has sought to reform the law to boost foreign companies' interests in their investments, although those efforts have foundered.

Technology has been one of the factors driving the opening up of Africa to deeper energy exploration. Offshore and deepwater drilling success in the Gulf of Mexico and Brazil led to prospecting now under way offshore in Ghana, Mozambique, and elsewhere. (See related story: "New Oil—And a Huge Challenge—for Ghana.") Jaffe says the Houston-based company Anadarko Petroleum has sought to transfer its success in "subsalt seismic" exploration technology, surveying reserves hidden beneath the hard salt layer at the bottom of the sea, to the equally challenging seismic exploration beneath the sands of the Sahara in Algeria, where it now has three oil and gas operations.

Africa also is seen as one of the few remaining oil-rich regions of the world where foreign oil companies can obtain production-sharing agreements with governments, contracts that allow them a share of the revenue from the barrels they produce, instead of more limited service contracts for work performed.

"You now have the technology to tap the resources more effectively, and the fiscal terms are going to be more attractive than elsewhere—you put these things together and it's been a hot place to drill," says Jaffe, who doesn't see the energy industry's interest in Africa waning, despite the increased terrorism risk. "What I think will happen in some of these countries is that the companies are going to reveal new securities systems and procedures they have to keep workers safe," she says. "I don't think they will abandon these countries."

This story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge.

Read More..

President Obama Sworn In for Second Term

President Barack Obama and Vice President Joe Biden today officially embarked on their second term, taking the Constitutionally mandated oath of office in two separate private ceremonies inside their homes.

Shortly before noon in the Blue Room of the White House, Obama raised his right hand, with his left on a family Bible, reciting the oath administrated by Chief Justice John Roberts. He was surrounded by immediate family members, including first lady Michelle Obama and daughters, Malia and Sasha.

"I did it," he said to his daughters after taking the oath.

Biden was sworn in earlier today by Justice Sonia Sotomayor, the first Hispanic to administer a presidential oath, in a ceremony at his official residence at the U.S. Naval Observatory. He was joined by more than 120 guests, including cabinet members, extended family and his wife, Dr. Jill Biden.

Because Jan. 20 -- the official date for a new presidential term -- falls on a Sunday this year, organizers delayed by one day the traditional public inauguration ceremony and parade down Pennsylvania Avenue.

Michael Reynolds-Pool/Getty Images

Vice President Joe Biden Sworn in for 2nd Term Watch Video

President Obama's 2nd Inauguration: Hundreds of Thousands to Attend Watch Video

Obama and Biden will each repeat the oath on Monday on the west front of the Capitol, surrounded by hundreds of dignitaries and members of Congress. An estimated 800,000 people are expected to gather on the National Mall to witness the moment and inaugural parade to follow.

The dual ceremonies in 2013 means Obama will become the second president in U.S. history to take the presidential oath four times. He was sworn in twice in 2008 out of an abundance of caution after Roberts flubbed the oath of office during the public administration. This year Roberts read from a script.

Franklin Roosevelt was also sworn in four times but, unlike Obama, he was elected four times.

This year will mark the seventh time a president has taken the oath on a Sunday and then again on Monday for ceremonial purposes. Reagan last took the oath on a Sunday in 1985.

Both Obama and Biden took the oath using a special family Bible. Obama used a text that belonged to Michelle Obama's grandmother LaVaughn Delores Robinson. Biden placed his hand on a 120-year-old book with a Celtic cross on the cover that has been passed down through Biden clan.

The official inaugural activities today also included moments of prayer and remembrance that marked the solemnity of the day.

Obama and Biden met at Arlington National Cemetery for a brief morning ceremony to place a wreath on the Tomb of the Unknowns, honoring military service members who served and sacrificed. The men stood shoulder to shoulder, bowing their heads as a bugler played "Taps."

Biden, who is Catholic, began the day with a private family mass at his residence. The president and first family attended church services at Metropolitan African Methodist Episcopal Church, a historically black church and site of two pre-inaugural prayer services for former President Bill Clinton and Vice President Al Gore and their families.

The Obamas and Bidens plan to participate in a church service on Monday morning at St. John's Episcopal, across Lafayette Park from the White House. They will also attend a National Prayer Service on Tuesday at the National Cathedral.

Later on Sunday evening, the newly-inaugurated leaders will attend a candlelight reception at the National Building Museum. The president and vice president are expected to deliver brief remarks to their supporters.

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