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^1~"NOVA"
White dwarfs are an example of a rather exotic type of matterthat physicists call “degenerate“. Most gasses expand when you heat them up: the increasing temperature causes the molecules to zip around faster which in turn increases the gas pressure. At extreme densities – like those seen in the cores of stars – the gas behaves rather peculiarly. The pressure is no longer a slave to temperature: turn up the heat and the gas does not expand. This counterintuitive behavior is crucial to what happens next on the white dwarf’s surface. As hydrogen from the donor star comes crashing down, the crushing force of gravity compresses it into a degenerate state and the intense radiation heats the gas to many millions of degrees. But having now obtained the properties of a degenerate gas, the newly acquired hydrogen shell doesn’t expand in response to the rapid heating, but holds its pressure steady. And now things get interesting. At temperatures exceeding 16 million degrees Celsius, conditions on the surface mimic those deep in the cores of stars and a thermonuclear explosion is the result. Hydrogen is rapidly fused into helium and the resulting release of energy blows the outer hydrogen shell off the surface of the white dwarf at speeds exceeding ten million kilometers per hour. In mere days, the white dwarf can increase its brightness by 100,000 times. It can then take months – or in some cases years – for the star to slowly fade from view. ^3~Mars Tugging On Approaching NASA Rover Curiosity
http://ow.ly/cKj0M The gravitational tug of Mars is now pulling NASA's car-size geochemistry laboratory, Curiosity, in for a suspenseful landing in less than 40 hours. With Mars looming ever larger in front of it, NASA's Mars Science Laboratory spacecraft and its Curiosity rover are in the final stages of preparing for entry, descent and landing on the Red Planet at 10:31 p.m. PDT Aug. 5 (1:31 a.m. EDT Aug. 6). Curiosity remains in good health with all systems operating as expected. Today, the flight team uplinked and confirmed commands to make minor corrections to the spacecraft's navigation reference point parameters. This afternoon, as part of the onboard sequence of autonomous activities leading to the landing, catalyst bed heaters are being turned on to prepare the eight Mars Lander Engines that are part of MSL's descent propulsion system. As of 2:25 p.m. PDT (5:25 p.m. EDT), MSL was approximately 261,000 miles (420,039 kilometers) from Mars, closing in at a little more than 8,000 mph (about 3,600 meters per second). This global map of Mars was acquired on Aug. 2, 2012, by the Mars Color Imager instrument on NASA's Mars Reconnaissance Orbiter. One global map is generated each day to forecast weather conditions for the entry, descent and landing of NASA's Curiosity rover. The active dust storm observed south of Curiosity's landing site on July 31 has dissipated, leaving behind a dust cloud that will not pose a threat to the landing. The map is a rectangular projection of Mars (from 90 degrees latitude to minus 90 degrees latitude, and minus 180 degrees longitude to 180 degrees east longitude). The landing site is located on the right side of the map, near 137 degrees east longitude and 4.5 degrees south latitude. The map shows water ice clouds at equatorial latitudes that are typical for late southern winter, when Mars is farther from the sun. Along the southern (bottom) part of the map there are patches of orange clouds, indicating dust lofted into the atmosphere. Small, short-lived dust storms are common at this time of year on Mars and were taken into account when Curiosity's landing system was designed and tested. Larger and more long-lived dust storms are very rare at this time of year. For the full story: http://ow.ly/cKj0M 
A new study suggests the Milky Way Galaxy formed from the inside-out, something that Nassim Haramein's physics predicted many years ago when he concluded that a super massive black hole forms in the center of galaxies FIRST and then the rest of the galaxy with its billions of stars form emerging out from the galactic center. Previously, it was presumed that so much matter accreted that eventually the center of a collecting mass of stars would collapse, producing a super massive black hole, forming the center of a new galaxy.
Read more: www.cam.ac.uk/research/news/gaia-eso-data-show-milky-way-may-have-formed-inside-out-and-provide-new-insight-into-galactic |
^2~88 Constellations
Andromeda Antlia Apus Aquarius Aquila Ara Aries Auriga Boötes Caelum Camelopardalis Cancer Canes Venatici Canis Major Canis Minor Capricornus Carina Cassiopeia Centaurus Cepheus Cetus Chamaeleon Circinus Columba Coma Berenices Corona Australis Corona Borealis Corvus Crater Crux Cygnus Delphinus Dorado Draco Equuleus Eridanus Fornax Gemini Grus Hercules Horologium Hydra Hydrus Indus Lacerta Leo Leo Minor Lepus Libra Lupus Lynx Lyra Mensa Microscopium Monoceros Musca Norma Octans Ophiuchus Orion Pavo Pegasus Perseus Phoenix Pictor Pisces Piscis Austrinus Puppis Pyxis Reticulum Sagitta Sagittarius Scorpius Sculptor Scutum Serpens Sextans Taurus Telescopium Triangulum Triangulum Australe Tucana Ursa Major Ursa Minor Vela Virgo Volans Vulpecula ^4~
ASTEROID SAMPLES COULD REVEAL MORE ABOUT SOLAR SYSTEM ORIGIN
Recent analysis of asteroid samples by Eizo Nakamura and colleagues at Okayama University and the Japan Aerospace Exploration Agency (JAXA) has shown that the formation of planets occurs when being constantly bombarded by particles from a few nanometres to tens of kilometres in size. This work was the first reported analysis of grains taken directly from a solar body in space, an asteroid named Itokawa. The pieces of asteroid were sampled by a probe sent by the Japan Aerospace Exploration Agency (JAXA) as part of the Hayabusa mission; it is the first time samples from an asteroid have been returned to Earth. The Hayabusa mission is part of a continuing mission to understand how asteroids formed and evolved. The mission sampled fragments from the 500 metre long asteroid Itokawa in 2005 and returned them to Earth in 2010 within a capsule which was parachuted into the Australian Outback. Itokawa is the third planetary body to have samples of it returned to Earth, after Apollo/Luna samples from the Moon and 'Stardust' samples from comet Wild 2. Meteorites, asteroids that have fallen to Earth, go through significant surface changes when they enter the atmosphere. The Itokawa samples contain chondritic material which has been unmodified by the melting and differentiation that occurs to meteorites. The smallest of these samples was just 40 microns, or millionths of a metre, in diameter and they were cut into pieces using focused beams of electrically charged ions for analysis under microscopes. Analysis using mass spectrometry has confirmed that the oxygen isotope ratios differed from rocks found on Earth, confirming the extra-terrestrial origin of 4 of the 5 samples. Scanning electron microscopy identified craters 100-200 nm in size as well as particles adhered to the asteroid surface. These features show that the bombardment by particles in space occurred down to the submicrometre size, and that low-gravity bodies such as asteroids also had their surface shaped by impacts. A type of feldspar was found within the grains that form during slow cooling, from temperatures of 860 °C. As these temperatures and cooling dynamics could not be achieved in a rock with a radius of only 300 metres, it is likely the asteroid Itokawa was originally much larger. There were a large number of glassy particles on the asteroid surface as well as iron particles. The chemistry and textures of Itokawa’s surface show long-term bombardment of equilibrated chondritic material, at scales of 10−9 to 104 metres. The first dust grains ever samples from the surface of an asteroid confirm that asteroids are shaped by bombardment of high-speed microscopic grains. Scientists from the University of Manchester are now about to analyse pieces of Itokawa. 70 samples have been released for international analysis among 11 international teams; 7 of the 70 samples are being studied at the University of Manchester. The University was selected because it hosts the most sensitive system in the world for analysing the rare gases xenon and krypton. Using equipment like this, the team plans to find out how rapidly and by which processes the surface of the asteroid is being changed, and whether asteroids like Itokawa could have delivered material to Earth in the solar system’s early history. The researchers hope the work will provide more information of the early history of the solar system and the formation of the planets. The image shows microscopic views of an asteroid sample collected by Japan's Hayabusa probe. Tiny bits of grain have adhered to the sample from impacting meteorite. -TEL http://phys.org/news/2012-10-asteroid-fragments-hayabusa-hint-solar.html; http://phys.org/news/2012-03-evolving-planets-bumpy.html#jCp; http://www.space.com/14691-asteroid-impacts-hayabusa-meteorite-samples.html; Eizo Nakamura et al, Space environment of an asteroid preserved on micrograins returned by the Hayabusa spacecraft, Proceedings of the National Academy of Sciences, February 27, 2012. doi: 10.1073/pnas.1116236109 Image credit: http://www.pnas.org/content/109/11/E624.full.pdf+html |
