Opps. Let's just post the story:
Planets in Sky with Diamonds
Uranus, Neptune Gasses May Produce Jewels
S A N F R A N C I S C O, Sept. 30 ? Uranus and Neptune may
be giant diamond factories, pressing out millions of the
precious stones under the pressure of billions of tons of
hydrogen, researchers said today.
Experiments that aimed to re-create the heat and pressure on the two
planets produced tiny diamonds ? and what looked a lot like oil, Robin
Benedetti and colleagues at the University of California at Berkeley
reported in the journal Science.
Benedetti and colleagues set up an experiment in which they tried to
simulate the enormous pressures and heat that are believed to exist on
Uranus and Neptune.
Reproduced High Pressure
Knowing there are large amounts of methane in their atmospheres,
Benedetti used special equipment to subject the methane to the
equivalent of the pressures on Uranus and Neptune ? 100,000 to
500,000 times the atmospheric pressure on Earth.
?I squeezed a little piece of methane between two diamonds,?
Benedetti, a graduate student studying planetary physics, said in an
interview.
Then she added heat.
?I shone an infrared laser onto it and I found a significant chemical
reaction when it got hot...Some of the methane decomposed completely
to carbon in diamond form.?
Methane is a molecule made up of four hydrogen atoms linked to a
carbon atom.
Carbon Leftovers Cling Together
Some of the hydrogen in the methane broke away from the carbon,
leaving the carbon to form pure diamonds. The hydrogen and a few of
the carbon atoms that were left chained into hydrocarbons, Benedetti?s
team reported.
She looked at the tiny diamonds in a microscope and also used a
technique known as X-ray crystallography to image them.
Spectral images of the soup she made showed the hydrocarbons were
very similar to oil, she said, although she stressed it was not exactly like
the fuel oil pumped on Earth.
What was more interesting to Benedetti than the creation of two of
the most precious minerals on Earth was the ability to model in the
laboratory what is happening on a planet billions of miles away.
Not Just a Gassy Blob
Once thought to be two big frozen, gassy blobs, Neptune and Uranus
have, in recent years, shown themselves to be dynamic, interesting
planets, both with rings like Saturn?s.
Astronomers have gleaned a lot of information from spectral images
taken with telescopes, and from images collected by the Voyager 2
mission when the tiny spacecraft flew by the two planets.
?If you picture it in your mind, there is a big atmosphere of hydrogen
and helium. Underneath that, there is a soup of water, ammonia and
methane under pressure from the kilometers of hydrogen above,?
Benedetti said.
The methane would be under so much pressure from the weight of
the hydrogen and helium above that it would be solid, rather than in the
gas form more common on Earth, she added.
?Either underneath or mixed in with the water and ammonia and
methane there are rocks and metals and stuff.?
Benedetti said this was one of the first pictures anyone has drawn of
what is actually going on in the outer planets.
?We used to just make these lists ? that inside these planets there is
hydrogen and helium and ammonia and methane and water,? she said.
?Now we know a little bit of what they are doing.?
PHIL |
