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The Platypus is stranger than you think.

Platypuses have no nipples.  After the young hatch, the mother oozes milk from the pores all over her body.

The male platypus has a poison barb on the inside of its hind legs.  The purpose of this weapon is uncertain.

While often compared to the beaver, the platypus is only about 20 inches in length -- more comparable to the size of the muskrat.

The Platypus bill is actually just an elongated muzzle covered with much the same kind of tough skin found on a dog's nose.  This bill contains an electrically-sensitive organ that can detect the electrical signatures of the small aquatic animals it eats.

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Welcome to Everything Science
The alpine marmot spreads into the Catalan Pyrenees PDF Print
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Everything Biology
Written by Everything Science   
Mar 09, 2010 at 12:00 AM

Researchers from the Centre for Ecological Research and Forestry Applications (CREAF) and the Autonomous University of Barcelona (UAB) have demonstrated, using a map of the potential distribution, the alpine marmot's capacity for adaptation in the fields of the Pyrenees. Its quick proliferation makes it a successful example of species introduction.

alpine marmot
The alpine marmot spreads into the Catalan Pyrenees.

Credit: Maximilian Naar.

At the end of the Pleistocene (10,000 years ago), the increase in temperatures brought an end to the alpine marmot (Marmota marmota) in the Pyrenees, but between 1950 and 1988, the French government introduced around 400 specimens into the Pyrenees. The first appearances in Spain date back to 1962-1964 in the valley of Otal (Huesca).

"As an herbivore that lives in colonies, its impact on the flora of the alpine and subalpine fields can be significant. In addition, it can be a key competitor for other herbivores that it coexists with, like the ptarmigan", Bernat Claramunt, main author and researcher in CREAF and in UAB, explains to SINC adding that the impact on the ptarmigan is "very low".

But to determine the magnitude of the direct or indirect effects of the presence of the alpine marmot on the alpine community, the team of scientists from CREAF-UAB, together with the association for environmental studies LUTRA, has ascertained the potential extent of the expansion of this species.

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Scientists discover 'catastrophic event' behind the halt of star birth in early galaxy formation PDF Print
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Everything Space
Written by Everything Science   
Mar 09, 2010 at 12:00 AM

Scientists have found evidence of a catastrophic event they believe was responsible for halting the birth of stars in a galaxy in the early Universe.

The researchers, led by Durham University's Department of Physics, observed the massive galaxy as it would have appeared just three billion years after the Big Bang when the Universe was a quarter of its present age.

 
galaxy growth
This is an observation showing gas in the galaxy SMM J1237+6203 seen using the Gemini Observatory’s Near-Infrared Integral Field Spectrometer (NIFS). The contours show how the blast of energy is traveling through the galaxy.

Credit: Dave Alexander/Mark Swinbank, Durham University, and Gemini Observatory

According to their findings the galaxy exploded in a series of blasts trillions of times more powerful than any caused by an atomic bomb. The blasts happened every second for millions of years, the scientists said.

The explosions scattered the gas needed to form new stars by helping it escape the gravitational pull of the galaxy called SMM J1237+6203, effectively regulating its growth, the scientists added.

They believe the huge surge of energy was caused by either the outflow of debris from the galaxy's black hole or from powerful winds generated by dying stars called supernovae.

The research, funded by the Royal Society and the Royal Astronomical Society, is published in the Monthly Notices of the Royal Astronomical Society. Observations were carried out using the Gemini Observatory's Near-Infrared Integral Field Spectrometer (NIFS).

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Biggest, deepest crater exposes hidden, ancient moon PDF Print
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Everything Space
Written by Everything Science   
Mar 06, 2010 at 12:00 AM

Shortly after the Moon formed, an asteroid smacked into its southern hemisphere and gouged out a truly enormous crater, the South Pole-Aitken basin, almost 1,500 miles across and more than five miles deep.

"This is the biggest, deepest crater on the Moon -- an abyss that could engulf the United States from the East Coast through Texas," said Noah Petro of NASA's Goddard Space Flight Center in Greenbelt, Md. The impact punched into the layers of the lunar crust, scattering that material across the Moon and into space. The tremendous heat of the impact also melted part of the floor of the crater, turning it into a sea of molten rock.

 
elevation map
This elevation map covering the eastern portion of South Pole-Aitken basin, including the Apollo Basin, was made using data from Japan’s Kaguya spacecraft. The false colors indicate height; red represents highlands, and blue represents the lowest areas. Dashed circles mark the location of the main and inner ring of Apollo.

Credit: Japan Aerospace Exploration Agency/NASA

That was just an opening shot. Asteroid bombardment over billions of years has left the lunar surface pockmarked with craters of all sizes, and covered with solidified lava, rubble, and dust. Glimpses of the original surface, or crust, are rare, and views into the deep crust are rarer still.

Fortunately, a crater on the edge of the South Pole-Aitken basin may provide just such a view. Called the Apollo Basin and formed by the later impact of a smaller asteroid, it still measures a respectable 300 miles across.

"It's like going into your basement and digging a deeper hole," said Petro. "We believe the central part of the Apollo Basin may expose a portion of the Moon's lower crust. If correct, this may be one of just a few places on the Moon where we have a view into the deep lunar crust, because it's not covered by volcanic material as many other such deep areas are. Just as geologists can reconstruct Earth's history by analyzing a cross-section of rock layers exposed by a canyon or a road cut, we can begin to understand the early lunar history by studying what's being revealed in Apollo."

Petro presents his result Thursday, March 4 during the Lunar and Planetary Science meeting in Houston, Texas.

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Dark matter lens used to measure age of universe PDF Print
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Everything Space
Written by Everything Science   
Mar 01, 2010 at 12:00 AM

Astronomers from the United States and Europe have used a gravitational lens -- a distant, light-bending clump of dark matter -- to make a new estimate of the Hubble constant, which determines the size and age of the universe.

A paper describing the work appears in the March issue of The Astrophysical Journal.

 
dark matter lens

This image taken by the Hubble Space Telescope shows gravitational lens B1608. The objects A, B, C and D are all images of the same background object, distorted by the lens. G1 and G2 are two galaxies within the lens itself.

Credit: Hubble Space Telescope

The Hubble constant has previously been calculated by using NASA's Hubble Space Telescope to look at distant supernovae, and by measurements of the cosmic microwave background -- radiation leftover from the Big Bang, said Chris Fassnacht, associate professor of physics at UC Davis. The new method provides an independent check on the other two, he said.

A gravitational lens is a distant object, such as a galaxy surrounded by dark matter, that exerts a gravitational pull on light passing through it. Other galaxies behind the lens, from our point of view, appear distorted. In the case of the object B1608+656, astronomers on Earth see four distorted images of the same background object.

Fassnacht began studying B1608+656 as a graduate student a decade ago. Because the mass distribution of the lens is now well understood as a result of recent Hubble Space Telescope observations, it is possible to use it to calculate the Hubble constant, he said.

It works something like this. Two photons of light leave the background galaxy at the same time and travel around the lens, their paths distorted in different ways by the gravitational field so that they arrive on Earth at slightly different times. Based on that time delay, it is possible to calculate the distance of the entire route, and then infer the Hubble constant.

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