News / Science & Technology

    Study: Earth-Like Planets Closer Than Expected

    This artist’s conception shows a habitable planet with two moons orbiting a red dwarf star. (CfA)
    This artist’s conception shows a habitable planet with two moons orbiting a red dwarf star. (CfA)
    VOA News
    Astronomers say there could be as many as 4.5 billion Earth-like planets orbiting stars in the Milky Way galaxy, and the nearest of them could be practically next door, in cosmic terms.

    Scientists at the Harvard-Smithsonian Center for Astrophysics, after analyzing data from NASA's Kepler space telescope, calculated that six percent of the galaxy's 75 billion red dwarf stars have potentially habitable, Earth-sized planets. Red dwarfs -- which are smaller, cooler and much dimmer than our own Sun - are the most common stars in the galaxy, so the closest Earth-like planet could be just 13 light years away, the astronomers conclude in their new study.

    "We thought we would have to search vast distances to find an Earth-like planet," said Harvard astronomer and lead author Courtney Dressing at a Cambridge, Massachusetts, news briefing. "Now we realize another Earth is probably in our own backyard, waiting to be spotted."

    Working from Kepler's 158,000-star catalog, Dressing culled all the red dwarfs and profiled their sizes and temperatures, as well as the number of planet candidates in orbit around them. She narrowed this planet list down to those of just the right size, temperature and distance from their host star to harbor liquid water and, possibly, life as we know it.

    Dressing's analysis found just three planetary candidates that were both warm and approximately Earth-sized. Statistically, that meant that six percent of all red dwarf stars throughout the galaxy should have an Earth-like planet.

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

    Our sun is surrounded by a swarm of red dwarf stars. In fact, about 75 percent of the closest stars are red dwarfs. They are good places to look for Earth-like planets not only because they are so numerous. Their smaller size also makes it easier for astronomers to spot a relatively large Earth-size planet as it transits across the star's disk.

    The Harvard astronomers say locating nearby, Earth-like worlds will require a dedicated small space telescope, or a large network of ground-based telescopes. And they are hopeful that follow-up studies with instruments like the soon-to-be-operational Giant Magellan Telescope in Chile and the James Webb Space Telescope -- due to be launched in 2018 - could eventually tell us whether any warm, transiting planets have an atmosphere and life-friendly chemistry.

    Since red dwarf stars last much longer than Sun-like stars, the astronomers say their analysis raises the possibility that life on one of their Earth-like planets would be much older and more evolved than life on Earth.

    The results of the study are published in The Astrophysical Journal.

    You May Like

    Russian-Backed Offensive in Syria Pushes War to Tipping Point

    As threat to Aleppo and rebel forces grows, US plan to negotiate becomes less and less appealing for Syrian government, says one military analyst

    IS Runs Timber Smuggling Business in Afghanistan, Officials Say

    Government turning blind eye to smuggling, according to tribal leaders; Afghanistan's forest cover dropped by 50 percent in three decades, experts say

    Video White House Seeks $1.8 Billion to Combat Zika

    Obama administration says funding would 'support essential strategies to combat the virus' such as rapidly expanding mosquito control programs, accelerating vaccine research

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    'No Means No' Program Targets Sexual Violence in Kenyai
    X
    February 08, 2016 4:30 PM
    The organizers of an initiative to reduce and stop rape in the informal settlements around Kenya's capital say their program is having marked success. Girls are taking self-defense classes while the boys are learning how to protect the girls and respect them. Lenny Ruvaga reports from Nairobi.
    Video

    Video 'No Means No' Program Targets Sexual Violence in Kenya

    The organizers of an initiative to reduce and stop rape in the informal settlements around Kenya's capital say their program is having marked success. Girls are taking self-defense classes while the boys are learning how to protect the girls and respect them. Lenny Ruvaga reports from Nairobi.
    Video

    Video New Hampshire Voters Are Independent, Mindful of History

    Once every four years, the northeastern state of New Hampshire becomes the center of the U.S. political universe with its first-in-the-nation presidential primary. What's unusual about New Hampshire is how seriously the voters take their role and the responsibility of being among the first to weigh in on the candidates.
    Video

    Video Chocolate Lovers Get a Sweet History Lesson

    Observed in many countries around the world, Valentine’s Day is sometimes celebrated with chocolate festivals. But at a festival near Washington, the visitors experience a bit more than a sugar rush. They go on a sweet journey through history. VOA’s June Soh takes us to the festival.
    Video

    Video 'Smart' Bandages Could Heal Wounds More Quickly

    Simple bandages are usually seen as the first line of attack in healing small to moderate wounds and burns. But scientists say new synthetic materials with embedded microsensors could turn bandages into a much more valuable tool for emergency physicians. VOA’s George Putic reports.
    Video

    Video Bhutanese Refugees in New Hampshire Closely Watching Primary Election

    They fled their country and lived in refugee camps in neighboring Nepal for decades before being resettled in the northeastern U.S. state of New Hampshire -- now the focus of the U.S. presidential contest. VOA correspondent Aru Pande spoke with members of the Bhutanese community, including new American citizens, about the campaign and the strong anti-immigrant rhetoric of some of the candidates.
    Video

    Video Researchers Use 3-D Printer to Produce Transplantable Body Parts

    Human organ transplants have become fairly common around the world in the past few decades. Researchers at various universities are coordinating their efforts to find solutions -- including teams at the University of Pennsylvania and Rice University in Houston that are experimenting with a 3-D printer -- to make blood vessels and other structures for implant. As VOA’s Greg Flakus reports from Houston, they are also using these artificial body parts to seek ways of defeating cancerous tumors.
    Video

    Video Helping the Blind 'See' Great Art

    There are 285 million blind and visually impaired people in the world who are unable to enjoy visual art at a museum. One New York photographer is trying to fix this situation by making tangible copies of the world’s masterpieces. VOA correspondent Victoria Kupchinetsky was there as visually impaired people got a feel for great art. Joy Wagner narrates her report.
    Video

    Video Sanders, Clinton Battle for Young Democratic Vote

    Despite a narrow loss to former Secretary of State Hillary Clinton in last week's Iowa Democratic caucuses, Vermont Senator Bernie Sanders secured more than 80 percent of the vote among those between the ages of 18 and 29. VOA correspondent Aru Pande talks to Democrats in New Hampshire about who they are leaning towards and why in this week's primary.
    Video

    Video German Artists to Memorialize Refugees With Life Jacket Exhibit

    Sold in every kind of shop in some Turkish port towns, life jackets have become a symbol of the refugee crisis that brought a million people to Europe in 2015.  On the shores of Lesbos, Greece, German artists collect discarded life jackets as they prepare an art installation they plan to display in Germany.  For VOA, Hamada Elrasam has this report from Lesbos, Greece.
    Video

    Video E-readers Help Ease Africa's Book Shortage

    Millions of people in Africa can't read, and there's a chronic shortage of books. A non-profit organization called Worldreader is trying to help change all that one e-reader at a time. VOA’s Deborah Block tells us about a girls' school in Nairobi, Kenya where Worldreader is making a difference.
    Video

    Video Genius Lets World Share Its Knowledge

    Inspired by crowdsourcing companies like Wikipedia, Genius allows anyone to edit anything on the web, using its web annotation tool
    Video

    Video In Philippines, Mixed Feelings About Greater US Military Presence

    In the Philippines, some who will be directly affected by a recent Supreme Court decision clearing the way for more United States troop visits are having mixed reactions.  The increased rotations come at a time when the Philippines is trying to build up its military in the face of growing maritime assertiveness from China.  From Bahile, Palawan on the coast of the South China Sea, Simone Orendain has this story.
    Video

    Video Microcephaly's Connection to Zika: Guilty Until Proven Innocent

    The Zika virus rarely causes problems for the people who get it, but it seems to be having a devastating impact on babies whose mothers are infected with Zika. VOA's Carol Pearson has more.
    Video

    Video Stunning Artworks Attract Record Crowds, Thanks to Social Media

    A new exhibit at the oldest art museum in America is shattering attendance records. Thousands of visitors are lining up to see nine giant works of art that have gotten a much-deserved shot of viral marketing. The 150-year-old Smithsonian American Art Museum has never had a response quite like this. VOA's Julie Taboh reports.