Robot inquisition keeps witnesses on the right track

MEMORY is a strange thing. Just using the verb "smash" in a question about a car crash instead of "bump" or "hit" causes witnesses to remember higher speeds and more serious damage. Known as the misinformation effect, it is a serious problem for police trying to gather accurate accounts of a potential crime. There's a way around it, however: get a robot to ask the questions.

Cindy Bethel at Mississippi State University in Starkville and her team showed 100 "witnesses" a slide show in which a man steals money and a calculator from a drawer, under the pretext of fixing a chair. The witnesses were then split into four groups and asked about what they had seen, either by a person or by a small NAO robot, controlled in a Wizard of Oz set-up by an unseen human.

Two groups - one with a human and one a robot interviewer - were asked identical questions that introduced false information about the crime, mentioning objects that were not in the scene, then asking about them later. When posed by humans, the questions caused the witnesses' recall accuracy to drop by 40 per cent - compared with those that did not receive misinformation - as they remembered objects that were never there. But misinformation presented by the NAO robot didn't have an effect.

"It was a very big surprise," says Bethel. "They just were not affected by what the robot was saying. The scripts were identical. We even told the human interviewers to be as robotic as possible." The results will be presented at the Human-Robot Interaction conference in Tokyo next month.

Bilge Mutlu, director of the Human-Computer Interaction Laboratory at the University of Wisconsin-Madison, suggests that robots may avoid triggering the misinformation effect simply because we are not familiar with them and so do not pick up on behavioural cues, which we do with people. "We have good, strong mental models of humans, but we don't have good models of robots," he says.

The misinformation effect doesn't only effect adults; children are particularly susceptible, explains the psychologist on the project, Deborah Eakin. Bethel's ultimate goal is to use robots to help gather testimony from children, who tend to pick up on cues contained in questions. "It's a huge problem," Bethel says.

At the Starkville Police Department, a 10-minute drive from the university, officers want to use such a robotic interviewer to gather more reliable evidence from witnesses. The police work hard to avoid triggering the misinformation effect, says officer Mark Ballard, but even an investigator with the best intentions can let biases slip into the questions they ask a witness.

Children must usually be taken to a certified forensic child psychologist to be interviewed, something which can be difficult if the interviewer works in another jurisdiction. "You might eliminate that if you've got a robot that's certified for forensics investigations, and it's tough to argue that the robot brings any memories or theories with it from its background," says Ballard.

The study is "very interesting, very intriguing", says Selma Sabanovic, a roboticist at Indiana University. She is interested to see what happens as Bethel repeats the experiment with different robot shapes and sizes. She also poses a slightly darker question: "How would you design a robot to elicit the kind of information you want?"

This article appeared in print under the headline "The robot inquisition"

It's all about how you say it

When providing new information, rather than helping people recall events (see main story), a robot's rhetoric and body language can make a big difference to how well it gets its message across.

Bilge Mutlu of the University of Wisconsin-Madison had two robots compete to guide humans through a virtual city. He found that the robot which used rhetorical language drew more people to follow it. For example, the robot saying "this zoo will teach you about different parts of the world" did less well than one saying "visiting this zoo feels like travelling the world, without buying a plane ticket". The work will be presented at the Human-Robot Interaction conference in Tokyo next month.

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S Korean activists jailed for unauthorised visit to North

SEOUL: A South Korean court jailed an elderly left-wing activist for four years on Friday for making an unauthorised trip across the border to North Korea.

Ro Su-Hui, 69, was convicted of violating a strict security law that penalises pro-Pyongyang activity and bans citizens from going to the North without prior permission.

Another activist, Won Jin-Wook, received a three-year prison sentence for communicating with North Korean officials to arrange Ro's trip.

Ro, 69, entered the North via China in March last year for a memorial service marking the 100th day since the death of long-time ruler Kim Jong-Il.

He praised new ruler Kim Jong-Un during his time in Pyongyang and was arrested in July when he returned home.

"Stern punishment is inevitable because he made a secret visit to North Korea without permission and was involved in (pro-North Korean) activities, even if he knew that his activities would be used for propaganda," the court said in its ruling.

Seoul did not send any official representatives to Kim Jong-Il's funeral and approved trips only by two private delegations.

- AFP/xq

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Alleged cop killer: I have no family, 'I'm terminating yours'

Ex-cop at center of California manhunt

Ex-cop at center of California manhunt

Ex-cop at center of California manhunt

Ex-cop at center of California manhunt

Ex-cop at center of California manhunt

Ex-cop at center of California manhunt

Ex-cop at center of California manhunt

Ex-cop at center of California manhunt

STORY HIGHLIGHTS

• NEW: With snow coming, authorities continue to hunt for the suspect near Big Bear Lake


• Police believe former cop Christopher Jordan Dorner shot three officers, killing one


• This was days after he allegedly killed two people, one a retired LAPD officer's daughter


• In an 11-page manifesto, Dorner promises "war" on police and their families

Los Angeles (CNN) -- A former Los Angeles cop with military training vowed war against other men in blue Thursday, leaving one officer dead days after he allegedly killed two other people to begin a wave of retribution for being fired, police said.

The focus of the intensive, expansive manhunt is Christopher Jordan Dorner, a 270-pound former Navy lieutenant who has professed his venom against LAPD officers he claimed ruined his life by forcing him out of his dream job.

Dorner blames one retired officer for bungling his appeal to get his job back in an 11-page manifesto, in which he also complained of mistreatment by the LAPD. In that letter -- provided to CNN by an LAPD source -- he vowed to violently target police officers and their families, whoever and wherever they are.

"I will bring unconventional and asymmetrical warfare to those in LAPD uniform whether on or off duty," Dorner wrote.

"I never had the opportunity to have a family of my own, I'm terminating yours."

Authorities believe he followed through on his threats early Thursday by shooting a Riverside, California, police officer and two others. A day earlier, Irvine police named Dorner a suspect in the double slayings Sunday of a woman -- identified by Los Angeles police as the daughter of a retired LAPD officer -- and her fiance.

"My opinion of the suspect is unprintable," said Riverside police Chief Sergio Diaz, hours after one of his officers was killed. "The manifesto, I think, speaks for itself (as) evidence of a depraved and abandoned mind and heart."

The violence, as well as Dorner's background as a police officer and expert marksman, left police on edge around Southern California.

Suspect's grudge dates back to 2007 complaint

In Torrance, LAPD officers guarding one of Dorner's alleged targets mistakenly opened fire on a blue pickup truck that resembled one Dorner was thought to be driving, said Los Angeles police Chief Charlie Beck.

The gunfire left two people wounded, Beck said. Torrance police also fired on another blue pickup, but no one was injured in that incident, according to a senior law enforcement source.

In downtown Los Angeles, police wearing body armor patrolled outside their own iconic headquarters.

Police have good reason to be fearful, the chief said.

"Of course, he knows what he's doing. We trained him," Beck said. "He was also a member of the armed forces. It is extremely worrisome and scary, especially to the officers involved."

The manhunt for Dorner spanned hundreds of miles and numerous counties. By Thursday afternoon, it was largely centered around Big Bear Lake -- about 100 miles east of Los Angeles -- where authorities found the truck the suspect allegedly used in the Riverside shooting.

Police confirmed that the vehicle, which was burnt out when it was found, belonged to Dorner by its vehicle identification number, San Bernardino County Sheriff John McMahon said.

This discovery spurred more officers to converge on the area to conduct beefed up patrols, staff checkpoints and go to every residence in the mountain community. McMahon acknowledged the fire may have been set as a diversionary tactic, though law enforcement isn't taking any chances. Early Thursday evening, he said that aerial and K9 searches on the ground will "continue as long as we can" -- though snow is coming -- and urged locals to be on alert.

"He could be anywhere at this point, and that's why we're searching door to door," the sheriff said.

1 cop dies in 'cowardly ambush'

It all started Sunday when Dorner allegedly killed two people in Irvine, according to police.

Police identified the victims as Monica Quan and her fiance Keith Lawrence.

Quan, 27, was the daughter of retired Los Angeles police Officer Randal Quan, LAPD Officer Tenesha Dobine told CNN. In his manifesto, Dorner said Quan handled his appeal.

On Tuesday, Dorner checked into the Navy Gateway Inns and Suites on San Diego's large naval base, Cmdr. Brad Fagan said.

Dorner likely had access to the hotel because he'd been honorably discharged from the Navy Reserve, said the Navy spokesman. Having retired February 1 as a lieutenant, Dorner worked with mobile inshore undersea warfare units and provided security on oil platforms in Iraq, according to Pentagon records. He was rated as a rifle marksman and pistol expert.

"He did not physically check out" Wednesday as expected, Fagan told reporters.

Police in San Diego say a man who could have been Dorner tried to hijack a boat there on Wednesday. Someone later found a wallet containing Dorner's identification and an LAPD detective's badge near the San Diego airport, according to police. It was unclear whether the badge was legitimate.

Timeline in manhunt for former L.A. cop

By about 1 a.m. Thursday, the scene had shifted about 100 miles north to Corona, California.

There, a pair of LAPD officers on a protection detail were flagged down by a citizen who reported seeing the suspect's vehicle, LAPD Deputy Chief Jose Perez said.

The officers chased the vehicle and caught up to it on an Interstate 15 off-ramp.

"The officers were fired upon with a shoulder weapon," Perez said, with one of them suffering a "graze wound" to his head. The police returned fire, while the suspect set off once again.

About 20 minutes later, two police officers were in their car at a stop light in Riverside when Dorner allegedly pulled up beside them.

That driver unleashed "multiple rounds" from a rifle at the officers, riddling the cop car with bullets and leaving a 34-year-old officer, who had been on the Riverside force for 11 years, dead, according to Diaz. The other officer, 27, was "seriously wounded but we expect a full recovery," the Riverside police chief said.

It was "a cowardly ambush," said Diaz, claiming Dorner has "no connection" to his city.

A good Samaritan picked up one of their police radios and called dispatchers to send help, Riverside police said.

KTLA: Manhunt for former cop after officers shot

Suspect calls attacks 'a necessary evil'

In addition to posting his manifesto online, Dorner reached out directly to CNN, mailing a parcel to AC360 anchor Anderson Cooper's office at CNN in New York.

The package arrived on February 1 and was opened by Cooper's assistant. Inside was a hand-labeled DVD, accompanied by a yellow Post-it note reading, in part, "I never lied" -- apparently in reference to his 2008 dismissal from the LAPD.

The package also contained a coin wrapped in duct tape. The tape bears the hand-written inscription: "Thanks, but no thanks, Will Bratton." It also had letters that may be read as "IMOA", which could be a commonly used Internet abbreviation for "Imagine a More Open America," or possibly "1 MOA," which means one minute of angle, perhaps implying Dorner was notably accurate with a firearm.

The coin is a souvenir medallion from former LAPD Chief William Bratton, of a type often given out as keepsakes. This one, though, was shot through with bullet holes: three bullet holes to the center and another shot nicked off the top.

The editorial staff of AC360 and CNN management were made aware of the package Thursday. Upon learning of its existence, they alerted Bratton and law enforcement.

Bratton headed the LAPD at the time Dorner was dismissed.

Dorner challenged his firing for years, losing at every turn. First, the police department's Board of Rights rejected his appeal. Then, in October 2011, a judge ruled against his appeal, according to court records.

Beck, the Los Angeles police chief, said Thursday that Dorner's case had been "thoroughly reviewed" and said the department would not apologize to Dorner or clear his name.

But as his manifesto shows, Dorner is showing no sign of relenting.

The suspect's manifesto

He complained he had been railroaded out of the department after reporting police brutality by another officer. Dorner also complained of a continuing culture of racism and brutality in the LAPD.

Attacks on other police officers and their families, he said, are "a necessary evil that I do not enjoy but must partake and complete for substantial change to occur within the LAPD and reclaim my name."

KCBS: Riverside officer fatally shot

"Look your wives/husbands and surviving children directly in the face and tell them the truth as to why your children are dead," Dorner wrote.

Such a chilling warning prompted Los Angeles police to set up 40 protective details in an effort to safeguard people listed in Dorner's letter, Beck said.

The chief acknowledged that this effort was taxing the department, which has been placed under tactical alert, meaning all officers must stay on duty.

"It's extremely, extremely manpower intensive," Beck said. "But the safety of my employees, people that come on the job to protect the lives of strangers, is extremely important to me. And I will expend whatever resource is necessary."

KABC: Former cop shoots three officers

CNN's AnneClaire Stapleton, Sara Weisfeldt, Barbara Starr, Pete Janos, Mallory Simon and Deanna Hackney contributed to this report.

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Despite adoption ban, N.J. couple brings home Russian tot

(CBS News) FREEHOLD, N.J. -- It's been about a month since Russian President Vladimir Putin banned Americans from adopting Russian children. It was widely seen as a retaliation for a new U.S. law targeting Russians who have violated human rights. At the time, 1,000 American families were in the middle of the adoption process.

CBS News first met Robert and Kim Summers a month ago. They were just weeks away from picking up their new son Preston from a Russian orphanage, when Putin announced the ban.

Foreign adoptions by Americans down 7 percent
U.S. family in limbo after Russia adoption ban

"I cannot put into words how my wife and I feel right now," Robert said at the time. "And we ask Putin, please, consider alternate means, but don't let these children suffer. Please. That's all we ask."

Despite the ban, the Summers decided to travel to Russia. They weren't sure whether they would return to the U.S. with their child.

"We did not know. We just prayed and kept the faith and just kept believing that, you know, all of our efforts would pay off," said Kim.

It was mid-January when they visited Preston in his orphanage outside Moscow. They finalized his paperwork and went to pick up his passport at a Russian government office.

U.S. family in limbo after Russia adoption ban
Russia seeks to reassure U.S. adoptive parents
Foreign adoptions by Americans down 7 percent

"She looked at it and she said in Russian, 'Americans? I thought there was a ban on Americans. How could we give them this passport?'" Kim recalled.

"We held our breath and I gasped for air and I said, oh no. Please, don't let us go through all this and we're going to have problems," Robert said.

Robert and Kim Summers.

/

CBS News

The Summers returned the next day and found out the ban did not apply to them because a judge had already signed off on their adoption before the law was passed.

Five days later, they left Russia and brought Preston home.

"Robert and I looked at each other and we said, it's over, it's over. And I can't even tell you the relief. And how elated we are," said Kim. "I completely understand when a mother says that she takes one look at her newborn child and is instantly in love with that child. I'm in love with him. I'm in love with him, and I do believe he's in love with us, too."

The State Department estimates just 50 American families, whose adoptions have been approved by judges, will be allowed to leave Russia with their new children. The Summers consider themselves blessed to be among them.

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Alleged Cop-Killer Has Calif. Region on Edge

The truck owned and driven by suspected cop killer Christopher Dorner during his alleged rampage through the Los Angeles area was found deserted and in flames on the side of Bear Mountain, Calif., this afternoon.

Heavily armed SWAT team members descended onto Bear Mountain from a helicopter manned with snipers today to investigate the fire. The San Bernadino Sheriff's Department confirmed the car was Dorner's.

Dorner, a former Los Angeles police officer and Navy reservist, is believed to have killed one police officer and injured two others early this morning in Riverside, Calif. He is also accused of killing two civilians on Sunday after releasing a scathing "manifesto" alleging grievances committed by the police department while he worked for it and warning of coming violence toward cops.

Read More About Chris Dorner's Allegations Against the LAPD

Heavily armed officers spent much of Thursday searching for signs of Dorner, investigating multiple false leads into his whereabouts and broadcasting his license plate and vehicle description across the California Highway System.

Around 3:45 p.m. ET, police responded to Bear Mountain, where two fires were reported, and set up a staging area in the parking lot of a ski resort. They did not immediately investigate the fires, but sent a small team of heavily armed officers up in the helicopter to descend down the mountain toward the fire.

Christopher Dorner: Ex-Cop Wanted in Killing Spree Watch Video

Engaged California Couple Found Dead in Car Watch Video

Missing Ohio Mother: Manhunt for Ex-Boyfriend Watch Video

The officers, carrying machine guns and searching the mountain for any sign of Dorner, eventually made it to the vehicle and identified it as belonging to Dorner. They have not yet found Dorner.

Late this afternoon, CNN announced that Dorner had sent a package containing his manifesto and a DVD to its offices.

PHOTOS: Former LAPD Officer Suspected in Shootings

Police officers across Southern California were on the defensive today, scaling back their public exposure, no longer responding to "barking-dog calls" and donning tactical gear outdoors.

Police departments have stationed officers in tactical gear outside police departments, stopped answering low-level calls and pulled motorcycle patrols off the road in order to protect officers who might be targets of Dorner's alleged rampage.

"We've made certain modifications of our deployments, our deviations today, and I want to leave it at that, and also to our responses," said Chief Sergio Diaz of the police department in Riverside, Calif., where the officers were shot. "We are concentrating on calls for service that are of a high priority, threats to public safety, we're not going to go on barking dog calls today."

Sgt. Rudy Lopez of the Los Angeles Police Department said Dorner is "believed to be armed and extremely dangerous."

Early Thursday morning, before they believe he shot at any police officers, Dorner allegedly went to a yacht club near San Diego, where police say he attempted to steal a boat and flee to Mexico.

He aborted the attempted theft when the boat's propeller became entangled in a rope, law enforcement officials said. It was then that he is believed to have headed to Riverside, where he allegedly shot two police officers.

"He pointed a handgun at the victim [at the yacht club] and demanded the boat," said Lt. David Rohowits of the San Diego Police Department.

Police say the rifle marksman shot at four officers in two incidents overnight, hitting three of them: one in Corona, Calif., and the two in Riverside, Calif.

Read More..

Today on New Scientist: 6 February 2013

Open Richard III DNA evidence for peer review

A good case has been made that a skeleton unearthed from a car park is that of the last Plantagenet king of England - it's time to share the data

Universal bug sensor takes guesswork out of diagnosis

A machine that can identify all bacteria, viruses and fungi known to cause disease in humans should speed up diagnosis and help to reduce antibiotic resistance

Choking China: The struggle to clear Beijing's air

As pollution levels return to normal in China's capital after a record-breaking month of smog, what can be done to banish the smog?

Genes mix across borders more easily than folk tales

Analysing variations in folk tales using genetic techniques shows that people swap genes more readily than stories, giving clues to how cultures evolve

Sleep and dreaming: Slumber at the flick of a switch

Wouldn't it be wonderful to pack a good night's sleep into fewer hours? Technology has the answer - and it could treat depression and even extend our lives too

Closest Earth-like planet may be 13 light years away

A habitable exoplanet should be near enough for future telescopes to probe its atmosphere for signs of life

Lifelogging captures a real picture of your health

How can lifelogging - wearing a camera round your neck to record your every move - reveal what's healthy and unhealthy in the way we live?

Musical brains smash audio algorithm limits

The mystery of how our brains perceive sound has deepened, now that musicians have broken a limit on sound perception imposed by the Fourier transform

Magnitude 8 earthquake strikes Solomon Islands

A major earthquake has caused a small tsunami in the Pacific Ocean, killing at least five people

Nuclear knock-backs on UK's new reactors and old waste

Plans to build new reactors in the UK are stalling as yet another company pulls out, and there is still nowhere to store nuclear waste permanently

Amateur astronomer helps Hubble snap galactic monster

An amateur astronomer combined his pictures with images from the Hubble archive to reveal the true nature of galactic oddball M106

Nightmare images show how lack of sleep kills

Fatigue has been blamed for some of worst human-made disasters of recent decades. Find out more in our image gallery

Read More..

Boeing Dreamliner to make special one-time flight

WASHINGTON: A Boeing 787 Dreamliner will fly for the first time in three weeks in a so-called ferry flight after the company won permission on Wednesday from US regulators.

In the special one-time flight, the plane -- with no passengers and just the minimum crew needed to fly it -- will travel on Thursday from Forth Worth, Texas, where it was being painted, back to Boeing's assembly plant in Everett in the northwestern state of Washington.

The 50-strong fleet of Boeing's newest plane was grounded January 16 because of repeated problems with its lithium-ion battery. One of them caught fire on an All Nippon Airways flight in Boston a week earlier.

The Federal Aviation Administration said that before the ferry flight, the crew must carry out a number of inspections to be sure the batteries and cables show no signs of damage.

"The pre-flight checklist will include a mandatory check for specific status messages that could indicate possible battery problems," the FAA said.

"While airborne, the crew must continuously monitor the flight computer for battery-related messages, and land immediately if one occurs."

- AFP/xq

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Obama agrees to give drone documents to Congress

By Lesa Jansen, CNN

updated 8:27 PM EST, Wed February 6, 2013

The U.S. MQ-9 Reaper unmanned aircraft vehicle has been used to take out key targets in the war on terror.

STORY HIGHLIGHTS

• The move comes on the eve of confirmation hearings for CIA director nominee John Brennan


• The drone program has been shrouded in secrecy, which has been criticized by senators


• The policy paper will go to congressional intelligence committees

Washington (CNN) -- Amid new controversy over his administration's targeted killing of American citizens overseas by drones, President Barack Obama has yielded to demands that he turn over to Congress classified Justice Department legal advice seeking to justify the policy, an administration official said.

The president's move comes on the eve of confirmation hearings Thursday for his CIA director nominee John Brennan and amid complaints from senators, including several Democrats, about secrecy surrounding the drone policy.

"Today, as part of the president's ongoing commitment to consult with Congress on national security matters, the president directed the Department of Justice to provide the congressional Intelligence committees access to classified Office of Legal Counsel advice related to the subject of the Department of Justice White Paper," an administration official said.

The 16-page white paper -- titled "Lawfulness of a Lethal Operation Directed Against a U.S. Citizen who is a Senior Operational Leader of Al Qaida or an Associated Force" -- is a policy paper rather than an official legal document.

Memo backs U.S. using lethal force against Americans overseas

The president, the official said, was turning over the information because he believes the scrutiny and debate is healthy.

Opinion: Bring drones out of the shadows

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Sequestration already cutting into national defense

(CBS News) WASHINGTON -- There is a much bigger Washington fiscal crisis coming in three weeks, when automatic, across-the-board budget cuts go into effect unless Congress finds another way. In Washington lingo, the budget cuts are called sequestration, and they're already cutting into national defense.

Watch: Scott Pelley speaks with President Barack Obama about sequestration, at left.

Late Wednesday afternoon, the 5,000 crew members of the aircraft carrier Truman got the word: they will not be leaving their home port of Norfolk, Va., for the Persian Gulf this Friday, as planned.

Their deployment is being postponed due to the looming budget crisis. Vice Admiral Mark Fox says that means the U.S. will have only one -- instead of the normal two -- aircraft carriers in the Persian Gulf.

Vice Admiral Mark Fox

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CBS News

"What it does change is the opportunity to have additional capability immediately," Fox says. "There will be additional time, distance associated with bringing another vessel over if that's required."

Fox says the move will save "in the hundreds of millions of dollars."

The postponement of the Truman's deployment -- along with that of a guided missile cruiser -- is the most visible effect of the threat of automatic budget cuts, known as sequestration, compounded by the absence of a new budget for fiscal year 2013. It's a double-whammy which has a normally affable Defense Secretary Leon Panetta hot under the collar.

In farewell remarks, Panetta rails against Congress, sequestration
Obama calls on Congress to avert sequester
Congress digs in for sequester battle -- again

"This is not a game," he declared Wednesday in a farewell speech at Georgetown University. "This is reality."

If sequestration takes effect at the beginning of March, Panetta says the Department of Defense will have to cut $46 billion in the remaining seven months of the fiscal year.

"We will furlough as many as 800,000 D.O.D. civilians around the country for up to 22 days," he said Wednesday. "They could face a 20 percent cut in their salary. You don't think that's going to impact on our economy?"

The cuts will not affect combat operations in Afghanistan. But troops in the field would take a hit in the pocket. A planned pay raise could be cut nearly in half.

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Galaxy May Be Full of 'Second Earths'

You may look out on a starry night and get a lonely feeling, but astronomers now say our Milky Way galaxy may be thick with planets much like Earth -- perhaps 4.5 billion of them, according to the Harvard-Smithsonian Center for Astrophysics.

Astronomers looked at data from NASA's Kepler space telescope in orbit, and conclude that 6 percent of the red dwarf stars in the Milky Way probably have Earth-like, habitable planets. That's a lot by space standards, and since red dwarfs are very common -- they make up three out of four stars in our part of the galaxy -- we may have a lot more neighbors than we thought.

The nearest of them, astronomers said today, could be 13 light-years away -- not exactly commuting distance, since a light-year is six trillion miles, but a lot closer than most yellow stars like Earth's sun.

Video: Are We Alone? Kepler's Mission

David A. Aguilar/Harvard-Smithsonian Center for Astrophysics

"We thought we would have to search vast distances to find an Earth-like planet. Now we realize another Earth is probably in our own backyard, waiting to be spotted," said Courtney Dressing, an astronomer at the Harvard-Smithsonian Center, in announcing the findings today. The results will be published in The Astrophysical Journal.

David Charbonneau, a co-author, said, "We now know the rate of occurrence of habitable planets around the most common stars in our galaxy. That rate implies that it will be significantly easier to search for life beyond the solar system than we previously thought."

Red dwarfs are older, smaller and dimmer than our sun, but a planet orbiting close to one could be sufficiently warmed to have liquid water. Dressing and her colleagues cited three possible planets that were spotted by Kepler, which was launched in 2009. One is 90 percent as large as Earth, and orbits its red sun in just 20 of our days.

There is no saying what such a world would actually be like; the Kepler probe can only show whether distant stars have objects periodically passing in front of them. But based on that, scientists can do some math and estimate the mass and orbit of these possible planets. So far, Kepler has spotted more than 2,700 of them in the small patch of sky it has been watching.

There are estimated to be 200 to 400 billion stars in the Milky Way -- which is probably a pretty average galaxy. So the new estimate implies a universe with tremendous numbers of Earth-like planets, far beyond our ability to count.

Pictures: Final Frontier: Images From the Distant Universe

Could they be friendly to life? There's no way to know yet, but space scientists say that if you have the right ingredients -- a planet the right size, temperatures that allow for liquid water, organic molecules and so forth -- and the chances may be good, even on a planet that is very different from ours.

"You don't need an Earth clone to have life," said Dressing.

Read More..