Friday, July 24, 2009

Auroras In Northern And Southern Hemispheres Are Not Identical Identical

Norwegian researchers have shown that the auroras in the Northern and the Southern hemispheres can be totally asymmetric. These findings contradict the commonly made assumption of aurora being mirror images of each other. In a study published in the July 24 issue of Science, researchers Amy Clement and Robert Burgman from the University of Miami's Rosenstiel School of Marine and Atmospheric Science and Joel Norris from Scripps Institution of Oceanography at UC San Diego begin to unravel this mystery. Using observational data collected over the last 50 years and complex climate models, the team has established that low-level stratiform clouds appear to dissipate as the ocean warms, indicating that changes in these clouds may enhance the warming of the planet.

In this study, macaque monkeys using brain signals learned how to move a computer cursor to various targets. What the researchers learned was that the brain could develop a mental map of a solution to achieve the task with high proficiency, and that it adhered to that neural pattern without deviation, much like a driver sticks to a given route commuting to work

The mass of molecules is traditionally measured using mass spectrometry, in which samples consisting of tens of thousands of molecules are ionized, to produce charged versions of the molecules, or ions. Those ions are then directed into an electric field, where their motion, which is choreographed by both their mass and their charge, allows the determination of their so-called mass-to-charge ratio. From this, their mass can ultimately be ascertained ceasuri

Beyond asteroids

This large debris disk is similar to the Kuiper Belt, which encircles the solar system and contains a range of icy bodies from dust grains to objects the size of dwarf planets, such as Pluto.

Asteroid belts are rocky and metallic debris left over from the early stages of planet formation. Their presence around other stars signals that rocky planets like Earth could be orbiting in the system's inner regions, with massive gas planets

Becker's team found 2006 SQ372 by applying a specialized computer searching algorithm to data taken for a completely different purpose: finding supernova explosions billions of light years away to measure the expansion of the universe. The SDSS-II supernova survey scanned the same long stripe of sky, an area 1,000 times larger than the full moon, every clear night in the fall of 2005, 2006, and 2007.

circling near the belts' rims. In our own solar system, for example, there is evidence that Jupiter, which lies just beyond our asteroid belt, caused the asteroid belt to form long ago by stirring up material that would have otherwise coalesced into a planet. Nowadays, Jupiter helps keep our asteroid belt confined to a ring.

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For pressures between 100,000 and 400,000 atmospheres, the team, led by Eric Schwegler, found that ice melts as a molecular solid (similar to how ice melts in a cold drink). But in pressures above 450,000 atmospheres, there is a sharp increase in the slope of the melting curve due to molecular disassociation and proton diffusion in the solid, prior to melting, which is typically referred to as a superionic solid phase.

The simulation predict the properties of hydrogen-helium mixtures at the extreme pressures and temperatures that occur in Jupiter's interior, which cannot yet be studied with laboratory experiments. Applying techniques originally developed to study semiconductors, UC Berkeley's Burkhard Militzer, an assistant professor of earth and planetary science and astronomy, calculated the properties of hydrogen and helium for temperature, density and pressure at the surface all the way to the planet's center.

The team used computer models to study the possible atmospheric mass loss over a stellar lifecycle for exoplanets at orbiting distances of less than 0.06 AU where the planetary and stellar parameters are very well known from observations.

Sparkling away at magnitude 3.7 and appearing nearly as large as the full moon on the southern night sky, Omega Centauri is visible with the unaided eye from a clear, dark observing site. Even through a modest amateur telescope, the cluster is revealed as an incredible, densely packed sphere of glittering stars. But astronomers need to use the full power of professional telescopes to uncover the amazing secrets of this beautiful globular cluster.

The 49 planets considered in the study included hot gas giants, planets with masses similar or greater than that of Saturn and Jupiter, and hot ice giants, planets comparable to Uranus or Neptune. All the exoplanets in the sample were discovered using the transit method, where the size and mass of the planet is deduced by observing how much its parent star dims as it the planet passes in front of it.

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