The Ottumwa Courier

Community News Network

July 18, 2013

Origin of gold found in rare neutron-star collisions

Gold — atomic number 79, element symbol Au, the most widely beloved of the precious metals — might have its origin in extremely rare and violent explosions in the far reaches of outer space. The bling apparently begins with a blam.

For many years, scientists had theorized that the heavy elements of the periodic table, such as gold, platinum, lead and uranium, had their origin in supernova explosions. But the source, scientists announced Wednesday, might be even more exotic: the collision of two ultra-dense objects called neutron stars.

"We now have kind of a smoking gun," said Edo Berger, an astronomer who led the research at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

The elements on Earth are all of cosmic origin. Carbon and oxygen atoms in our bodies, for example, come from the interior of stars, where they were formed under high pressure and heat. They were later spewed into the universe in supernova explosions. It is literally true, as Carl Sagan was fond of saying, that we are all star stuff.

But what hasn't been known is whether these supernova events could account for the heaviest of the elements. A heavy element such as gold has 79 protons, 79 electrons and 118 neutrons. That's a lot of mass for one atom. Most of the elements are simpler; gold and the other heavy elements are cosmically extravagant.

The neutron stars might provide the explanation.

Neutron stars are the collapsed cores of stars that have exploded in a supernova. A neutron star might be roughly the diameter of Washington but contain as much mass as our sun, all of it crammed together by the force of gravity, until even the atoms have collapsed, leaving the object with the density of an atomic nucleus.

A teaspoon full of neutron-star material would weigh, on Earth, about 5 billion tons, Berger said.

Text Only
Community News Network
  • VIDEO: Boston bomb scare defendant appears in court

    The man accused of carrying a backpack containing a rice cooker near the Boston Marathon finish line on the anniversary of the bombings was arraigned Wednesday. He's being held on $100,000 bail.

    April 17, 2014

  • Consumer spending on health care jumps as Affordable Care Act takes hold

    Nancy Beigel has known since September that she would need hernia surgery. She couldn't afford it on her $11,000 yearly income until she became eligible for Medicaid in January through President Barack Obama's signature health care law.

    April 17, 2014

  • The case for separate beds

    The other night I slept on a twin bed in the guest room of the house I share with my husband and our two kids.
    It was the best night's sleep I've had in years.

    April 17, 2014

  • Raw oysters spike U.S. rise in bacterial infections, CDC reports

    Raw oysters, so good with hot sauce, increasingly can carry something even more unsettling to the stomach: A bacteria linked to vomiting, diarrhea and pain.

    April 17, 2014

  • To sleep well, you may need to adjust what you eat and when

    Sleep.  Oh, to sleep.  A good night's sleep is often a struggle for more than half of American adults.  And for occasional insomnia, there are good reasons to avoid using medications, whether over-the-counter or prescription.

    April 16, 2014

  • Doctors to rate cost effectiveness of expensive cancer drugs

    The world's largest organization of cancer doctors plans to rate the cost effectiveness of expensive oncology drugs, and will urge physicians to use the ratings to discuss the costs with their patients.

    April 16, 2014

  • Low blood-sugar levels make for grousing spouses

    Husbands and wives reported being most unhappy with their spouses when their blood-sugar levels were lowest, usually at night, according to research released this week in the Proceedings of the National Academy of Sciences. Missing a meal, dieting or just being hungry may be the reason, researchers said.

    April 16, 2014

  • Screen Shot 2014-04-16 at 12.51.22 PM.png VIDEO: Toddler climbs into vending machine

    A child is safe after climbing into and getting stuck inside a claw crane machine at a Lincoln, Neb., bowling alley Monday.

    April 16, 2014 1 Photo

  • portraitoflotte.jpg VIDEO: From infant to teen in four minutes

    Dutch filmmaker Frans Hofmeester’s time lapse video of his daughter, Lotte — created by filming her every week from her birth until she turned 14 — has become a viral sensation.

    April 16, 2014 1 Photo

  • Victimized by the 'marriage penalty'

    In a few short months, I'll pass the milestone that every little girl dreams of: the day she swears - before family and God, in sickness and in health, all in the name of love - that she's willing to pay a much higher tax rate.

    April 15, 2014

Obituaries
Record
Facebook
AP National