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An international team has discovered the Spanish participation possible minimum mass for the emergence of a galaxy in which stars form. The statistic suggests that dark matter halos that surround galaxies must have at least a mass of 300 billion solar masses.
Only when it reaches a minimum halo mass of 300 billion suns, a galaxy forming stars can start efficiently”, explained to SINC Valtchanov Bruno Altieri and Ivan, two of the authors of the study published today Nature and researchers from the European Space Astronomy Centre (ESA) in Villanueva de la Canada (Madrid).
Scientists believe that the paradigm of cold dark matter (one of the proposals to explain the formation of cosmic structures) galaxies form early in the universe with dark matter halos of mass close to one million solar masses . Later, these halos begin to grow mass concentration or by the merger of other halos.
The study, led by the University of California (USA), when the mass of these halos exceeds 300 billion solar masses are statistically galaxies start forming stars.
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Researchers at the Institute of Physics Corpuscular (IFIC) and other European groups have studied the effects of the presence of dark matter in the Sun According to his calculations, the particles of low mass dark matter might be transferring energy from the core to the outer regions Sun, which influence the number of neutrinos reaching Earth
We assume that dark matter particles interact weakly with the atoms of the Sun, and what we have done is to calculate between what range can cause these interactions to better describe the structure and evolution of the Sun”, explains Marco Taoso SINC, researcher IFIC, a joint CSIC and University of Valencia.
Astrophysical observations suggest that our galaxy is placed in a halo of dark matter particles. According to the models, some of these particles, WIMPs (Weakly Interacting Massive Particles: weakly interacting massive particles) interact weakly with other normal, like atoms, and may be accumulating in the interior of stars. The study, published recently in the journal Physical Review D, explores this issue in the case of the Sun
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A team of researchers coordinated by the Astronomical Observatory of Paris (France) publishes today Nature details of the astronomical object most distant confirmed so far, the galaxy UDFy-38135539, as suggested by some images from the Hubble telescope. The authors report that its light was emitted more than 13 billion years, and that this galaxy has a redshift (redshifIn English) record of 8.6. UDFy-38135539 is also of interest for being a beacon of “reionization epoch” of the early universe.
An international team of astronomers has measured the distance to the most distant galaxy known. Through careful analysis of the faint glow of the galaxy, they found that the observed light was emitted when the Universe was only 600 million years old, “known as redshift of 8.6 (z = 8.55), as advises the European Southern Observatory (ESO).
The supertelescopio Very Large Telescope (VLT) ESO in Chile has allowed the observations, the first confirmation of a galaxy whose light is clearing the opaque fog of hydrogen filling the universe at that early period. This is the galaxy UDFy-38135539 and details of the research appears this week in the journal Nature.
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The European Space Agency (ESA ) has made the video Tracing the galaxy : from Hipparcos to Gaia (Charting the Galaxy – from Hipparcos to Gaia) to explain the details of the Gaia mission , a satellite that will map nearly a thousand million stars in the Milky Way. Now a group of researchers from the Department of Astronomy and Meteorology at the University of Barcelona has translated the video, which is distributed podcast, So that is already available in Castilian and Catalan.
The video Tracing the galaxy : from Hipparcos to Gaia (Charting the Galaxy – from Hipparcos to Gaia) the ESA said that the satellites the Gaia, which is slated for 2012 , will map more than a thousand million stars in space with an unprecedented degree of accuracy , and test theories about the origin and evolution of our galaxy. For each object , calculated parameters (position, speed, distance, physical, etc.). and give us a map of our galaxy in six dimensions.
Currently, the Gaia satellite is in the final stages of construction, assembly and testing. Some of the mirrors are finished others are being polished. In the central structure has a bull riding three feet in diameter and 80 % of the detectors also are ready.
In this project, working together over 400 European scientists, involved thirty researchers and technicians of the Department of Astronomy and Meteorology of the UB. Since this group has been carried out with the collaboration of the Generalitat of Catalonia , the translation and dubbing of video to bring the mission to the public.
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For the first time, a team of astronomers has been successful in investigating the earliest stages of the evolutionary history of our galaxy, the Milky Way. Scientists at the Institute of Astronomy Argelander at the University of Bonn and Max-Planck Institute for Radio Astronomy in Bonn, have concluded that our galaxy moved from its original homogenous state to a lumpy in just a few hundred million years.
The team of Pavel Kroupa and Michael Marks studied spherical groups of stars (globular clusters) found in the halo of the Milky Way, outside the spiral arms in one of which is the sun Every one of those globular clusters containing hundreds of thousands of stars and is believed to have formed at the same time as the protogalaxy that eventually became the Milky Way today.
Globular star clusters can be considered as fossils of early history of the galaxy, as has been shown that these clusters retain traces of the conditions under which they formed. The stars of the clusters were formed from a cloud of molecular gas (hydrogen relatively cold), which is not completely exhausted in the process of star formation. The residual gas was expelled by the winds and radiation from the newborn population of stars.
Due to this expulsion of gas, globular clusters underwent a process in which they lost to the stars that formed in its borders. This means that the current appearance of the clusters was directly influenced by what happened in his childhood.
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Astronomers have long known that in the hearts of most galaxies are massive black holes. Many of them may be up to billions more massive than our Sun. It seems that they can completely stop the process of star formation and the galaxy to condemn to a slow death.
Before the mass attracted by strong gravity, “falls” into a black hole, circling around her spiral, heat and radiates energy into the surroundings. For supermassive black holes may be the flow of energy so intense that the mass absorbed in September more than hundreds of billions of nearby stars.
One consequence is that the flow of energy from the galaxies ‘scattered’ gas and dust, then the material from which new stars are born. If this happens, the galaxy gradually “goes out”, because the old stars burn out and are replaced by new.
Asa Bluck from Nottingham University to meet the Royal Astronomical Society, presented the results of his team, the images taken in visible, infrared and X-ray spectrum studied the properties of some hundreds of galaxies.
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Some new images captured by the Hubble Space Fermi Gamma, NASA, shows the places where certain supernova remnants emit radiation one billion times more energetic than visible light. The images are astronomers a step closer to knowing in detail the origin of cosmic rays, consisting of particles that are among the most energy in the universe.
Cosmic rays consist mainly of protons that move through space at nearly the speed of light. On his journey through the galaxy, the particles are deflected by magnetic fields. This changes their paths and masks its origin.
Clearly know the origin of cosmic rays is one of the main objectives of the Fermi Telescope, as noted by Stefan Funk, an astrophysicist at the Kavli Institute for Cosmology and Particle Astrophysics (KIPAC), located partly in the Laboratory SLAC National Accelerator Facility, and partly at the University of Stanford, California.
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For the first time, astronomers have made direct measurements of the size and brightness regions where stars are born in a galaxy far away, thanks to a chance discovery with telescope APEX.
This galaxy is so distant and light has so many weather to reach us, as we see it as there was 10 billion years. A gravitational lensing cosmic bigger the galaxy, giving us a close-up view impossible to obtain otherwise. This lucky reveals a vibrant and vigorous activity star formation in galaxies in the early universe with stellar nurseries are forming hundred times faster than in more recent galaxies. This search is published online in the journal Nature.
The astronomers were busy observing a cluster Solid , Using the submillimeter wavelengths, when they discovered a new galaxy of unusual brightness, more distant than the cluster. It’s very distant galaxy the brightest ever observed in the submillimeter. It is so bright because the grains of cosmic dust in the galaxy shine after being heated by the radiation stars. This new galaxy was named SMM J2135-0102.
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Astronomers have glimpsed through physical trick back in time until only three billion years after the Big Bang and watched the area in which the stars had formed. It turned out that the then new stellar nurseries hurled stalwart 250 times faster than the similar region in our galaxy today.
Managed to identify four areas of star formation in distant galaxy from which to us went ten billion light years. Each of them in September more than a hundred times brighter than areas in which the stars formed in our galaxy, such as the Orion nebula.
So detailed images of stellar ‘population growth has so far managed to obtain only the galaxies in our vicinity. Look so far back in time and space, this time managed by the effect of gravitational lensing.
Observed area is hidden behind a giant cluster of galaxies nearer. They its gravity bends electromagnetic radiation like optical lens, which makes it difficult for the underlying galaxy appears to be sixteen times brighter and larger than life.
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The Herschel telescope, parked 1.5 million kilometers from Earth, was discovered in the Orion nebula, a number of chemicals important for the existence of life. This does not mean that Orion life actually exists. The nebula is very tempestuous.
Orion Nebula in our galaxy lies at a distance of about 1,600 light-years from Earth. The huge clouds of gas and dust in it created new stars. Analyzing the spectrum of infrared radiation captured in it, astronomers discovered the presence of a number of simple inorganic and organic substances, which may arise from complex organic molecules.
Infrared radiation from the Orion brought as evidence of the presence of water, carbon monoxide, formaldehyde, methanol, dimetyleteru, hydrocyanic acid or carbon dioxide.
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