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Mysteries of "The Redshift Desert" --Why Do Galaxies in the Early Universe Appear Old?

Some of the faintest spectra in the universe raise a glaring question: Why do Galaxies in the early universe appear old? Until recently, astronomers have been nearly blind when looking back in time to survey an era when most stars in the Universe were expected to have formed. This critical cosmological blind-spot was removed in 2011 by a team using the Frederick C. Gillett Gemini North Telescope located on Mauna Kea, Hawaii, showing that many galaxies in the young Universe are not behaving as they would have expected some 8-11 billion years ago.
The surprise: these galaxies appear to be more fully formed and mature than expected at this early stage in the evolution of the Universe.
"Theory tells us that this epoch should be dominated by little galaxies crashing together," said Dr. Roberto Abraham (University of Toronto) who was a Co-Principal Investigator of the team that conducted the observations at Gemini. "We are seeing that a large fraction of the stars in the Universe are already in place when the Universe was quite young, which should not be the case. This glimpse back in time shows pretty clearly that we need to re-think what happened during this early epoch in galactic evolution. The theoreticians will definitely have something to gnaw on!"
These observations are from a multinational investigation, called the Gemini Deep Deep Survey (GDDS), which used a special technique to capture the faintest galactic light ever dissected into the rainbow of colors called a spectrum. In all, spectra from over 300 galaxies were collected, most of which are within what is called the "Redshift Desert," a relatively unexplored period of the Universe seen by telescopes looking back to an era when the universe was only 3-6 billion years old.


"Goldilocks Planet Will Be Found Within Next Two Years"

Certainly you remember the story of Goldilocks and the tree bears told to you as a child by a knowing adult? What does a fairy tale have to do with Space exploration? As the numbers mount, it seems to be just a matter of time before Kepler finds what astronomers are really looking for: an Earth-like planet orbiting its star in the "Goldilocks zone"—that is, at just the right distance for liquid water and life.

"I believe Kepler will find a 'Goldilocks planet' within the next two years," says Shawn Domagal-Goldman, a researcher at NASA HQ who specializes in exoplanet biology. "We'll be able to point at a specific star in the night sky and say 'There it is—a planet that could support life!'"

Kepler has already located a few Earth-sized planets, but they are too close for comfort to their parent stars. These recent finds have heightened the sense that a big discovery is just around the corner.

But finding such a planet is just the first step. Getting to know it is much more difficult.



Vaccine to stop heart attacks could be here in 5 years

A vaccine delivered in an injection or nasal spray to prevent heart attacks could be available within five years.

Scientists have discovered that the drug stimulates the body's immune system to produce antibodies which prevent heart disease by stopping fat building up in the arteries.

It is the first time that the underlying cause of heart disease has been targeted. Current treatments focus on using drugs to reduce cholesterol levels and blood pressure.

The vaccine can cut the build up of fat in arteries by up to 70 per cent, according to tests by researchers at Lund University in Sweden. The fatty deposits cause arteries to narrow, meaning the body has to work harder to pump blood, and can lead to a heart attack.

Prof Peter Weissberg, the British Heart Foundation medical director, said the vaccine was "very promising".



See where the US wind blows

Caroline Morley, online picture researcher

As a child on a breezy spring day I once lost my kite. Once my tears had dried I imagined where the wind might take it and who might find it.
Digital artists Fernanda Viégas and Martin Wattenberg might have been able to tell me: they have created a live wind map of the US that traces the paths of the winds in close to real time. Once an hour the website takes the raw data from the National Digital Forecast Database and converts it into a seething mass of lines flowing over the landscape.
The artists, who lead Google's Big Picture visualisation research group in Cambridge, Massachusetts, state: "Our medium is data visualization, a technology developed by computer scientists to extract insights from raw numbers."
In this still frame from 11 am EDT today, we can see where the kite-flying weather is. Chicago is known as the Windy City: now we can see the winds coming down from Canada and the Great Lakes. There is also a swirl in the south and the strongest winds flowing across the west and north to Canada.



Lightning directed by laser beams

IT'S not quite Zeus, but at least it's not entirely myth. Lasers have been used for the first time to trigger and divert lightning bolts.

The idea of using a powerful laser to create a low-resistance path through the atmosphere - a virtual lightning rod - gained momentum in the 1990s. Lasers were developed that could generate terawatts (trillions of watts) of power for femtoseconds (millionths of billionths of a second). These created pulses so intense that they ripped electrons from air molecules, forming channels of ionised air along the beam path. These paths focused the laser light in high intensity zones called filaments, which kept the air ionised long after the laser passed through, but failed to trigger or direct lightning.

In 2008, a group led by André Mysyrowicz of the applied optics laboratory at ENSTA ParisTech in France took a trailer-sized laser to New Mexico for field experiments with clouds. The group found that its laser filaments increased electrical activity in storm clouds, but did not trigger lightning.

Now the group has reached two milestones on the road to practical lightning protection with a more compact laser. In one experiment in a military lab in Toulouse, France, they set up a high-voltage discharge with two possible targets about 2.5 metres away. With the laser off, the artificial lightning always hit the closer target. But with the laser on, generating a filament path to the farther target, the discharge went where it was directed.



It’s the Methane, S***** (Intellectually Challenged)

by Bob Brown on March 29, 2012 at 12:01 pm |

“Natural gas” is mostly methane (CH4), a relatively potent greenhouse gas. The concentration of methane in the Earth’s atmosphere is expressed as a mole fraction, nmol/mol (parts per billion, ppb). It was about 700 ppb in 1750; in 1998, it was 1745; it stayed flat for awhile but then began rising, to over 1850 ppb by 2010.

Methane is being released into the atmosphere by natural processes, it is a strong positive feedback to GW as the protective ice cover retreats and methane is released from permafrost and methane clathrates in the ocean.

But it is also being released by commercial fuel production at an increasing rate in the name of reducing CO2 release (from coal burning e.g.). In the production process and finally in combustion it combines with oxygen to produce water and CO2. Methane stays in the atmosphere about a decade with thirty times the GHG effect of CO2. It then converts to CO2 which stays around for centuries. One way of “controlling” methane release is to burn it off, producing the less potent CO2.

Recently our commercial production of shale gas has doubled by using the process of hydraulic fracturing the shale rock to produce shale gas. In the process, the leakage of the methane to the atmosphere is about 10%. So we are increasing methane release (along with toxic metals, hydrocarbons and radioactive material in the shale) from this gas production. Again we are plunging ahead without having carefully studied the environmental repercussions.

Once the climate modelers get methane feedback into their models, with the new sources of methane, expect to see new, more dire predictions of global warming. Already predictions from those who study the processes say there is a possibility of catastrophic warming if the net GH gases get above a “tipping point” (which some say has already been passed, some say in 15-35 years).

Of course we can all hope that the scientists are all wrong.

Friday TOON Roundup 3- The Rest





Friday TOON Roundup 2- Sinking like a rock

Friday TOON Roundup 1- Supremely arrogant

The most racist POS toon I've seen yet on the Zimmerman shooting

Can't find a contact or web site for this moron other than Cagle. Anybody?
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