News / Science & Technology

    Gassy Exoplanet has Earth-like Mass

    KOI-314c, shown in this artist's conception, is the lightest planet to have both its mass and physical size measured. (Harvard-Smithsonian Center for Astrophysics)
    KOI-314c, shown in this artist's conception, is the lightest planet to have both its mass and physical size measured. (Harvard-Smithsonian Center for Astrophysics)

    Related Articles

    Astronomers Discover Earth-sized 'Lava Planet'

    Life on the planet is unlikely as surface temperatures rang from 2,000 to 2,800 Celsius

    Study Finds Billions of Earth-like Planets

    Until now it was not known how common potentially habitable planets existed near sun-like stars, researchers say

    Astronomers Spot Water on Five Exoplanets

    NASA says the planets are likely 'hot Jupiters'
    VOA News
    Astronomers have discovered what they’re saying is the first planet outside our solar system, or exoplanet, with the same mass as Earth. But although its weight is similar to Earth, the planet is 60 percent larger in diameter.

    KOI-314c, which likely has a thick gaseous atmosphere, orbits a dim red dwarf star and is about 200 light-years away. The astronomers said it circles its star every 23 days and that its temperature is around 220 degrees Fahrenheit, too hot for life as we know it.

    "This planet might have the same mass as Earth, but it is certainly not Earth-like," says David Kipping of the Harvard-Smithsonian Center for Astrophysics (CfA), lead author of the discovery. "It proves that there is no clear dividing line between rocky worlds like Earth and fluffier planets like water worlds or gas giants."

    KOI-314c is only 30 percent denser than water. This suggests that the planet is enveloped by a significant atmosphere of hydrogen and helium hundreds of miles thick. It might have begun life as a mini-Neptune and lost some of its atmospheric gases over time, boiled off by the intense radiation of its star.

    Weighing such a small planet was a challenge. Conventionally, astronomers measure the mass of an exoplanet by measuring the tiny wobbles of the parent star induced by the planet's gravity. But this method is extremely difficult for a planet with Earth's mass. The previous record holder for a planet with a measured mass (Kepler-78b) weighed 70 percent more than Earth.

    To weigh KOI-314c, the team relied on a different technique known as transit timing variations (TTV). This method can only be used when more than one planet orbits a star. The two planets tug on each other, slightly changing the times that they transit their star.

    Using this technique, the astronomers actually found two planets. The second planet in the system, KOI-314b, is about the same size as KOI-314c but significantly denser, weighing about 4 times as much as Earth. It orbits the star every 13 days.

    The discovery was serendipitous, as the team was looking for exomoons, not exoplanets.

    "When we noticed this planet showed transit timing variations, the signature was clearly due to the other planet in the system and not a moon. At first we were disappointed it wasn't a moon but then we soon realized it was an extraordinary measurement," said Kipping.

    Kipping presented this discovery, which was based on data from NASA’s Kepler spacecraft, at the 223rd meeting of the American Astronomical Society.

    You May Like

    Video Pop Icon Prince Quietly Helped Afghan Orphans for Years

    He sent thousands of dollars to help an aid group rebuild a training center for orphan boy and girl scouts in Kabul, but kept his involvement secret

    Mali, a Way Station for Syrians Headed to Europe

    Another door may be closing for Syrians fleeing the conflict in their country, this time in Africa

    Britain’s Muslims See London Mayor Race as Victory

    Mere running of 45-year-old former government minister and son of Pakistani immigrants Sadiq Khan seen by many as turning point

    This forum has been closed.
    Comments
         
    There are no comments in this forum. Be first and add one

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Donations Rescue Afghan Parents, Children From Forced Labori
    X
    May 05, 2016 6:44 PM
    A Facebook campaign organized by a VOA radio host raised 150,000 Afghan rupees to rescue a family from forced labor at a brick kiln in Nangarhar province – the result of the father’s unpaid debt. Video by a VOA reporter in Jalalabad went viral this week and triggered the Facebook campaign.
    Video

    Video Donations Rescue Afghan Parents, Children From Forced Labor

    A Facebook campaign organized by a VOA radio host raised 150,000 Afghan rupees to rescue a family from forced labor at a brick kiln in Nangarhar province – the result of the father’s unpaid debt. Video by a VOA reporter in Jalalabad went viral this week and triggered the Facebook campaign.
    Video

    Video Kurdish Troops Recount Firefight Which Killed US Navy SEAL

    A U.S. Navy SEAL killed Tuesday, when Islamic State fighters punched through Kurdish lines in northern Iraq, was part of a quick reaction force sent to extract other U.S. troops trapped by the surprise offensive. VOA's Kawa Omar spoke with Kurdish troops in the town of Telskuf -- the scene of what U.S. officials called a "dynamic firefight."
    Video

    Video British Lawmakers Warn EU Exit Talks Could Last A Decade

    Leaving the European Union would mean difficult negotiations that could take years to complete, according to a bipartisan group of British lawmakers. While the group did not recommend a vote either way, the lawmakers noted trade deals between the EU and non-EU states take between four and nine years on average. Henry Ridgwell reports on the mounting debate over whether Britain should stay or exit the EU as the June vote approaches.
    Video

    Video NASA Astronauts Train for Commercial Space Flights

    Since the last Shuttle flight in 2011, the United States has been relying on Russian rockets to launch fresh crews to the International Space Station. But that may change in the next few years. NASA and several private space companies are developing advanced capsules capable of taking humans into low orbit and beyond. As VOA's George Putic reports, astronauts are already training for commercial spacecraft in flight simulators.
    Video

    Video US Worried Political Chaos in Iraq Will Hurt IS Fight

    The White House is expressing concern about rising political chaos in Iraq and the impact it could have on the fight against the Islamic State. The U.S. says Iraq needs a stable, central government to help push back the group. But some say Baghdad may not have a unified government any time soon. VOA's White House correspondent Mary Alice Salinas reports.
    Video

    Video Press Freedom in Myanmar Fragile, Limited

    As Myanmar begins a new era with a democratically elected government, many issues of the past confront the new leadership. Among them is press freedom in a country where journalists have been routinely harassed or jailed.
    Video

    Video Taliban Threats Force Messi Fan to Leave Afghanistan

    A young Afghan boy, who recently received autographed shirts and a football from his soccer hero Lionel Messi, has fled his country due to safety concerns. He and his family are now taking refuge in neighboring Pakistan. VOA's Ayaz Gul reports from Islamabad.
    Video

    Video Major Rubbish Burning Experiment Captures Destructive Greenhouse Gases

    The world’s first test to capture environmentally harmful carbon dioxide gases from the fumes of burning rubbish took place recently in Oslo, Norway. The successful experiment at the city's main incinerator plant, showcased a method for capturing most of the carbon dioxide. VOA’s Deborah Block has more.
    Video

    Video EU Visa Block Threatens To Derail EU-Turkey Migrant Deal

    Turkish citizens could soon benefit from visa-free travel to Europe as part of the recent deal between the EU and Ankara to stem the flow of refugees. In return, Turkey has pledged to keep the migrants on Turkish soil and crack down on those who are smuggling them. Brussels is set to publish its latest progress report Wednesday — but as Henry Ridgwell reports from London, many EU lawmakers are threatening to veto the deal over human rights concerns.
    Video

    Video Tensions Rising Ahead of South China Sea Ruling

    As the Philippines awaits an international arbitration ruling on a challenge to China's claims to nearly all of the South China Sea, it is already becoming clear that regardless of which way the decision goes, the dispute is intensifying. VOA’s Bill Ide has more from Beijing.
    Video

    Video Painting Captures President Lincoln Assassination Aftermath

    A newly restored painting captures the moments following President Abraham Lincoln’s assassination in 1865. It was recently unveiled at Ford’s Theatre in Washington, where America’s 16th president was shot. It is the only known painting by an eyewitness that captures the horror of that fateful night. VOA’s Julie Taboh tells us more about the painting and what it took to restore it to its original condition.
    Video

    Video Displaced By War, Syrian Artist Finds Inspiration Abroad

    Saudi-born Syrian painter Mohammad Zaza is among the millions who fled their home for an uncertain future after Syria's civil war broke out. Since fleeing Syria, Zaza has lived in Lebanon, Egypt, Jordan and now Turkey where his latest exhibition, “Earth is Blue like an Orange,” opened in Istanbul. He spoke with VOA about how being displaced by the Syrian civil war has affected the country's artists.

    Special Report

    Adrift The Invisible African Diaspora