Earth-sized planets in habitable zones are more common than previously thought

Mar. 12, 2013 ? The number of potentially habitable planets is greater than previously thought, according to a new analysis by a Penn State researcher, and some of those planets are likely lurking around nearby stars.

"We now estimate that if we were to look at 10 of the nearest small stars we would find about four potentially habitable planets, give or take," said Ravi Kopparapu, a post-doctoral researcher in geosciences. "That is a conservative estimate," he added. "There could be more."

Kopparapu detailed his findings in a paper accepted for publication in Astrophysical Journal Letters. In it, he recalculated the commonness of Earth-sized planets in the habitable zones of low-mass stars, also known as cool stars or M-dwarfs.

Scientists focus on M-dwarfs for several reasons, he explained. The orbit of planets around M-dwarfs is very short, which allows scientists to gather data on a greater number of orbits in a shorter period of time than can be gathered on Sun-like stars, which have larger habitable zones. M-dwarfs are also more common than stars like Earth's Sun, which means more of them can be observed.

According to his findings, "The average distance to the nearest potentially habitable planet is about seven light years. That is about half the distance of previous estimates," Kopparapu said. "There are about eight cool stars within 10 light-years, so conservatively, we should expect to find about three Earth-size planets in the habitable zones."

The work follows up on a recent study by researchers at the Harvard-Smithsonian Center for Astrophysics which analyzed 3,987 M-dwarf stars to calculate the number of Earth-sized planet candidates in cool stars' habitable zones -- a region around a star where rocky planets are capable of sustaining liquid water and therefore life. That study used habitable zone limits calculated in 1993 by Jim Kasting, now an Evan Pugh Professor in Penn State's Department of Geosciences. Kopparapu noticed that its findings, based on data from NASA's Kepler satellite, didn't reflect the most recent estimates for determining whether planets fall within a habitable zone.

These newer estimates are based on an updated model developed by Kopparapu and collaborators, using information on water and carbon dioxide absorption that was not available in 1993. Kopparapu applied those findings to the Harvard team's study, using the same calculation method, and found that there are additional planets in the newly determined habitable zones.

"I used our new habitable zone calculations and found that there are nearly three times as many Earth-sized planets in the habitable zones around these low mass stars as in previous estimates," Kopparapu said. "This means Earth-sized planets are more common than we thought, and that is a good sign for detecting extraterrestrial life."

Share this story on Facebook, Twitter, and Google:

Other social bookmarking and sharing tools:

---

Story Source:

The above story is reprinted from materials provided by Penn State. The original article was written by Anne Danahy.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

---

Journal Reference:

1. Ravi kumar Kopparapu. A revised estimate of the occurrence rate of terrestrial planets in the habitable zones around kepler m-dwarfs. Accepted to Astrophysical Journal Letters, 2013 [link]

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/most_popular/~3/QxbJe7eOkMc/130312152047.htm

Jack Klugman merry Christmas a christmas story twas the night before christmas santa Capital STEEZ George Bush

PFT: NFL, GE to partner in concussion study

AP

The Seahawks have made a bold, aggressive move to trade for Vikings receiver Percy Harvin, the 2009 NFL offensive rookie of the year.

And while the deal hinges on both Harvin passing a physical and the Seahawks and Harvin working out a contract, a source with knowledge of the situation tells PFT that the terms of a new contract are in place.

Harvin currently is traveling to Seattle.? On Tuesday morning, he?ll take a physical.? If he passes the physical (and it will be regarded as a shock if he doesn?t), the trade will be called in to the NFL after the new league year begins at 4:00 p.m. ET, and the contract will be signed.

Despite a report that Harvin wants to be paid in the range of Cardinals receiver Larry Fitzgerald and Lions receiver Calvin Johnson, both of those players are in the range of $16 million.? Per the source, Harvin?s deal won?t be close.

In reality, Harvin?s deal will be more in line with the current one-up high-jump that began last year with Bucs receiver Vincent Jackson with five years, $55.5 million, and which was extended by Chiefs wideout Dwayne Bowe and his five-year, $56 million deal.

Key factors to consider when assessing Harvin?s deal include the fact that he was still under contract for one year at $2.775 million; Jackson and Bowe were both starting from scratch.? While the total money could push Harvin past the $12 million annual threshold, the new-money analysis would yield a lower average.? A

Also, Harvin has been a major pain in the butt for the Vikings, pretty much since he got there.? The Vikings were ready to move on for a reason, and the Seahawks are assuming the risk that Harvin will bring with his immense talent a penchant for causing problems.? Getting Harvin into the second tier of receiver contracts given his history would be an accomplishment.

If Harvin becomes a headache, the Seahawks can?t claim ignorance.? Offensive coordinator Darrell Bevell spent two years with Harvin in Minnesota.? Bevell has seen the highs and the lows, and everything in between.

But, in reality, Bevell needs Harvin to be on his best behavior for only one year.? After making it to the interview list for multiple teams after the 2012 season, another potent performance by Seattle could launch Bevell into a head-coaching job of his own.

Which would put him miles and miles away from Seattle before Percy starts causing problems in the Pacific Northwest.

Source: http://profootballtalk.nbcsports.com/2013/03/11/nfl-ge-to-partner-in-concussion-study/related/

PSEG hocus pocus hocus pocus mta schedule PECO Hurricane Sandy update ellen degeneres

McConnell intends to force vote on defunding Obamacare (Washington Post)

Share With Friends: | | Politics - Top Stories News, News Feeds and News via Feedzilla.

Source: http://news.feedzilla.com/en_us/stories/politics/top-stories/290926555?client_source=feed&format=rss

food network good friday f/a 18 f 18 crash virginia tenebrae the lake house petrino arkansas

Man Overboard: GNOME Cofounder Joins the Mac Side

It seems that the FOSS community sees its ranks expand just about every day, as new fans of free and open source software join the fold. What's much less common is to see former advocates of Linux and FOSS change their minds and depart. That's pretty much what happened last week, when GNOME cofounder Miguel de Icaza announced that he has abandoned desktop Linux in favor of Apple's Mac platform.

Source: http://ectnews.com.feedsportal.com/c/34520/f/632000/s/296f5798/l/0L0Stechnewsworld0N0Crsstory0C774920Bhtml/story01.htm

weather new orleans orcl the hartford illinois primary 2012 michael bay zsa zsa gabor illinois primary

AP source: Obama poised to pick Perez for Labor

WASHINGTON (AP) ? Two people familiar with the process say President Barack Obama is close to naming Thomas Perez, a civil rights official in the Justice Department, as his choice to head the Department of Labor.

His nomination could come as early as Monday, the people familiar with the process said Saturday. They spoke on condition of anonymity because the official announcement has not yet been made.

If confirmed, Perez would replace Hilda Solis, who resigned in January.

White House spokesman Matt Lehrich declined to comment.

Perez was the first Latino elected to the Montgomery County Council in Maryland, where he served from 2002 to 2006.

Perez, 51, has led the Justice Department's Civil Rights Division since 2009 and previously served as Maryland's labor secretary. He is expected to have solid support from organized labor and the Hispanic community, which is eager to have Hispanic representation in Obama's Cabinet.

Perez would come to the Labor Department as Obama pushes a major immigration overhaul, which could include changes in how employers hire guest workers. Labor Department officials have also taken a prominent role in supporting Obama's effort to raise the federal minimum wage from $7.25 to $9 an hour.

At the Justice Department, Perez played a leading role in the decision to challenge voter ID laws in Texas and South Carolina that could restrict minority voting rights. A federal court later struck down the Texas law and delayed implementation of the law in South Carolina until after the 2012 election.

Perez was easily confirmed by the Senate for his Justice Department post, but since then, some GOP lawmakers have criticized his role in persuading the city of St. Paul, Minn., to withdraw a lending discrimination lawsuit from the Supreme Court. In exchange, the Justice Department declined to join two whistle-blower lawsuits against St. Paul that could have returned millions in damages to the federal government.

The St. Paul case had challenged the use of statistics to prove race discrimination under the 1968 Fair Housing Act, and Justice Department officials were concerned the court could strike down the practice.

A letter last year from four Republican lawmakers, including Sen. Chuck Grassley of Iowa and Rep. Darrell Issa of California, criticized Perez for a "quid pro quo arrangement" that potentially cost taxpayers more than $180 million.

Associated Press

Source: http://hosted2.ap.org/APDEFAULT/89ae8247abe8493fae24405546e9a1aa/Article_2013-03-10-US-Labor-Secretary/id-2a5e525d4a454332ade5d9801faee9b0

matt cain adastra holocaust remembrance day chesapeake energy dick clark death yom hashoah yolo

Xi3 starts Piston pre-orders: buy an early Steambox for under $1,000

While Xi3's Piston may only be a Steambox through its software optimization, that still leaves us with a milestone on our hands now that the system is available for pre-orders: it's the first Valve-blessed PC on sale. If you're willing to set aside just under $1,000 ($900 during SXSW), you can claim a Big Picture-friendly mini PC with an embedded, 3.2GHz version of AMD's quad-core A10 in addition to 8GB of RAM and a 128GB solid-state drive. There's no mention of the conventional spinning storage referenced at CES. Expansion is limited to larger-capacity SSDs, although that's not surprising when the entire computer is smaller than a GeForce GTX Titan. The real jolt will be the launch timing. Xi3 won't have Pistons shipping until around the holidays, which could leave some of us hunting for less-than-official (if considerably larger) substitutes for the full Steam experience.

Filed under: Desktops, Gaming

Comments

Via: Joystiq

Source: Xi3

Source: http://www.engadget.com/2013/03/10/xi3-starts-piston-pre-orders/

paul ryan michele bachmann donald trump Election 2012 map Election Results Map Early voting results BBC

10 things you need to know today: March 9, 2013

Venezuela mourns Hugo Chavez, the papal election process begins, and more in our roundup of the stories that are making news and driving opinion

1. UNEMPLOYMENT AT LOWEST LEVEL SINCE 2008
The Labor Department on Friday reported that the economy added 236,000 jobs in February, bringing the unemployment rate to 7.7 percent, down from 7.9 percent in January. The jobless rate is now at its lowest level since December 2008 ? before Barack Obama was sworn in for his first term as president. The report was almost uniformly positive, greatly outpaced analysts' expectations, and bolstered optimism that the labor market could finally escape the years-long pattern of plodding improvement that has so far characterized the economic recovery. "It's an outstanding report," says TD Bank Group economist Craig Alexander. "Not only are the headlines good but the details are good as well." [The Week]
??????????????????????????????

2.?CHAVEZ REMEMBERED AT STAR-STUDDED STATE FUNERAL
An A-list crowd of prominent Venezuelan celebrities gathered in Caracas on Friday to mourn their deceased president, Hugo Chavez, who died on Tuesday at the age of 58. Thirty-two heads of state, including Cuban President Raul Castro and Iranian President Mahmoud Ahmadinejad?were also in attendance to pay their respects. Following the ceremony, Nicolas Maduro, Chavez's vice president, was sworn in as interim president. [CNN]
??????????????????????????????

SEE MORE: Has the stock rally restored America's wealth?

3. CARDINALS WILL BEGIN CONCLAVE TO ELECT NEW POPE
Rome's Catholic cardinals voted Friday to begin the conclave ? or secret election ? of a new pope on Tuesday. All cardinals under the age of 80 are permitted to vote during the closed-door process. While there is so far no clear favorite, most recent conclaves have decided on a new pope within two days. [CNN]
??????????????????????????????

4.?SOUTH DAKOTA SIGNS LAW ALLOWING TEACHERS TO CARRY GUNS IN CLASS
Gov. Dennis?Daugaard?signed a bill into law on Friday that will allow teachers in South Dakota to carry guns in the classroom. While other states have provisions in their gun laws that make it possible for teachers to carry guns in class, South Dakota appears to be the first state to create a law explicitly for this reason. About two dozen states have proposed similar bills since the deadly shootings in December at Sandy Hook Elementary School in Newtown, Conn., but all of them have stalled. Supporters of the South Dakota law say it's important for the state, where some schools are too far from emergency responders. Opponents say the measure was rushed and doesn't make children safer. [New York Times]
??????????????????????????????

SEE MORE: Elizabeth Warren takes off the gloves

5.?GOOGLE SLASHES JOBS AT MOTOROLA
Google is laying off 1,200 employees at its Motorola Mobility unit. The cuts amount to 10 percent of the Motorola workforce. The internet search giant had already eliminated 4,000 Motorola jobs when it acquired the company in August. The latest move reinforces the impression some had that Google was more interested in Motorola's patents than its products. Motorola staffers got the latest news in a company email saying that "our costs are too high, we're operating in markets where we're not competitive and we're losing money." [Wall Street Journal]
??????????????????????????????

6.?CHINA'S EXPORTS SURGE UNEXPECTEDLY
New data from China showed that the country's exports jumped by 21.8 percent in February, crushing expectations. Analysts had expected a single-digit increase. The surge could be a sign of strengthening global demand. Offsetting the news: China's imports were surprisingly weak, falling 15 percent from a year earlier. On balance, analysts said, the data at least suggest that the world's second biggest economy is continuing on the path to recovery in 2013, after finishing strong in 2012. [Associated Press,?Reuters]
??????????????????????????????

SEE MORE: Scientists say Earth is hotter today than it has been for nearly all of the last 11,000 years

7.?PAST DECADE RANKS AMONG THE HOTTEST
A study published in the journal Science suggests that average global temperatures were higher in the past decade than they've been over most of the past 11,300 years. The decade 2000-2009 was one of the warmest since modern record-keeping began, but global mean temperatures didn't breach the levels of the early Holocene period, which they are now on track to do. If the scientists' forecasts are correct, the planet will be warmer in 2100 than it has been for 11,300 years. [Wall Street Journal]
??????????????????????????????

8.?WRIGLEY'S TO DEBUT CAFFEINATED CHEWING GUM
Wrigley's, the world's largest chewing gum company, is set to debut its Alert Energy Caffeine Gum at convenience stores next month. Each piece of gum will contain about half as much caffeine as a cup of coffee. The company has addressed the inevitable health concerns surrounding its product by stating that Alert Energy is marketed to adults ages 25 and older, adding that each package contains a warning label that says the gum is "not recommended for children or persons sensitive to caffeine." [Wall Street Journal]
??????????????????????????????

SEE MORE: The daily gossip: Disney is already making an Oz the Great and Powerful sequel, and more

9.?DOZENS SICKENED AT 'WORLD'S TOP' RESTAURANT
More than 60 people fell ill in February after dining at Copenhagen's Noma restaurant, which was rated the world's best restaurant from 2010-2012 by Restaurant Magazine. The sickened patrons suffered from vomiting and diarrhea during a five-day period, health officials said. It's unclear what caused the outbreak, but reports say the source may have been a sick kitchen employee. The managers of Noma have apologized. Noma charges up to $260 for a meal ? without drinks ? and reservations often must be made months in advance. [BBC]
??????????????????????????????

10.?BIEBER LASHES OUT AT PHOTOGRAPHER
Hours after getting treatment at a hospital for apparent breathing problems, 19-year-old singer Justin Bieber was captured on camera lunging at a photographer. The teen had fallen ill during a Thursday concert in London and was rushed to a hospital after finishing his show. On Friday, before getting into a car, Bieber's bodyguard restrained him when the young singer became angry and tried to push away a paparazzo. "Sometimes when people r shoving cameras in your face all day and yelling the worst thing possible at u...well I'm human," Bieber tweeted after the incident. [E Online]

SEE MORE: The week's best of the internet

View this article on TheWeek.com Get 4 Free Issues of The Week

Other stories from this section:

Like on Facebook?-?Follow on Twitter?-?Sign-up for Daily Newsletter

Source: http://news.yahoo.com/10-things-know-today-march-9-2013-081500323.html

mitt romney tax return flip saunders academy award nominations cynthia nixon cspan state of the union drinking game oscar noms