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The winds faster come from galaxies containing active galactic nuclei brighter
Massive flows of molecular gas that escape galaxies have been observed directly for the first time ESA Herschel Space Observatory. The winds recorded to be extraordinary for both size and speed: The fastest observed so far moves at a speed of more than one thousand kilometers per second.
The discovery is significant because its stars form the interstellar gas in galaxies and streams as intense as those found in some of them could herald the arrest of the formation of new stars in those cosmic structures.
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Two U.S. astronomers have discovered that small and faint stars known as red dwarfs are much more prolific than previously thought. So much so that experts say is likely that the total number of stars in the universe is three times higher than that previously thought. The study appears this week in the journal Nature.
Red dwarfs are relatively small and dim compared to stars like our Sun, and so astronomers were not able to detect so far in different galaxies to the Milky Way or in their nearest neighbors. For this reason scientists did not know the proportion of red dwarfs are within the stellar population of the universe.
Two astronomers from the Universities of Yale and Princeton (USA) have used instruments powerful Keck Observatory in Hawaii to detect the faint traces of red dwarfs in eight relatively nearby massive galaxies. Elliptical galaxies is located between 50 and 300 million light years away.
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Astronomers have developed a technique to trace the large cosmic structures without needing to detect individual galaxies.
Tables of Pointillist painters – primarily Georges Seurat and Paul Signac in the late nineteenthe century – are formed of points of color that , when viewed at a distance , merge into each other to reveal a broader picture.
Tzu -Ching Chang , University of Taipei , Taiwan , and colleagues have demonstrated the validity of a similar technique to study the large-scale structures in the Universe.
Studying the distribution of galaxies across a billion light years – the major structures – is an important issue to test cosmological models , and determine the amount of matter in the total energy of the universe . It seeks particularly to bridge the gap between large structures and heterogeneities in the early Universe , visible in the temperature fluctuations of the background radiation (the first light emitted in the Universe) .
The traditional approach is to identify the individual galaxies . One of the most comprehensive survey is the catalog SDSS2 , which locates a million galaxies up to distances of a few billion light years ( or a ” redshift ” z = 0,3).
The alternative method proposed by T.-C. Chang and his colleagues would trace the cosmic structures at higher redshift , that is to say further in the past . The astronomers used the radiotelescope at Green Bank , Virginia , United States , to conduct a survey of a large portion of the sky at 21 cm wavelength , for a redshift ( depth ) 0 53 to 1.12.
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About a quarter of the globular star clusters in our Milky Way came here from other galaxies, the team of scientists from Swinburne University of Technology in Australia. These globular clusters in other galaxies were formed and then traveled to ours, the Milky Way.
These star clusters made their journey in the last few billion years.
Previously, many astronomers have suspected that some globular star clusters, each containing between 10,000 and several million stars were beyond our galaxy, but it was difficult to identify with certainty which ones.
Using data collected by the Hubble Space Telescope, astronomer Duncan Forbes of that Australian university, and his Canadian colleague Terry Bridges, examined globular star clusters in the Milky Way.
The researchers then prepared the largest database of high quality that is aware of, to record the age and chemical properties of each of these clusters.
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With the cooperation of the doctoral Akosh Bogdan, the Max Planck Institute for Astrophysics, Marat Guilfanov, a researcher at the Institut d’Etudes Spatiales (IKI) of Russian Academy of Sciences, has refuted a hypothesis, which held firm until ‘Then, on the formation of Type Ia supernovae [1]. Their research showed that the most likely cause of the explosions of supernovae of this type was the merger of two white dwarf – the remains of stars “dead”. This conclusion is of exceptional importance for cosmology, since it is precisely these supernovae, which determine the pace of expansion of the Universe.
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A team of European researchers, which have involved a scientist at the Center for Astrobiology (CSIC-INTA), has found that the distant galaxy surveys that are performed with telescopes in the spectrum of hydrogen (the so-called Lyman-alpha line) do not collect 90% of the galaxies, as published in this week’s magazine Nature.
For some time, the scientific community was aware that most polls in the most distant regions of the Universe, based on the detection of light emitted by distant galaxies thousands of millions of years, did not detect a significant fraction of these objects. A job with the participation of the Astrobiology Center (Joint Center for Scientific Research Council-CSIC, and the National Institute of Aerospace Technology-INTA), has concluded that the unrecorded amount is 90% of distant galaxies. The research results are published in the latest issue of Nature.
The work, which has had the collaboration of CSIC researchers J. Miguel Mas-Hesse at the Center for Astrobiology, has been developed using a specific probe with two of the four giant telescopes (8.2 m diameter) providing the Very Large Telescope (VLT) of European Southern Observatory (ESO), the main intergovernmental European astronomical organization, which operates in three areas of Chile.
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New experimental data refute rival theories that the dynamics in an era primordial universe would have deviated from the description given by Einstein’s theory
An analysis of over 70,000 galaxies carried out by a research collaboration between ‘University of California at Berkeley, University of Zurich and Princeton University shows that the universe, at least up to a distance of 3.5 billion light years from Earth, follows the rules of the theory of general relativity.
Through the calculation of the number of galaxies that aggregate into Cluster and analyzing their speed and distortions due to intervening material, researchers have shown that Einstein’s theory explains the structure and dynamics of the universe than we do the next best alternative theories to the theory of general relativity.
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A team of U.S. and Swiss astrophysicists has found that general relativity theory of Einstein work at scales as large as those between the galaxies, published today by the journal Nature. To perform the study, researchers have relied on a sample of some 70,000 galaxies and have defined a new parameter for quantification.
A group of scientists from the Center of Princeton University (USA) and the Institute of Theoretical Physics at the University of Zurich (Switzerland) have tested the theory of Einstein’s general relativity and conclude that really works to large scales, between two and 50 megaparsecs (a parsec light equivalent to 3.2616 years) at a redshift of 0.32 in the spectrum. “We’ve done the first step of an amount that can detect deviations from general relativity, and so far it confirms the predictions, thus increasing our confidence in the theory and the current cosmological framework,” Reyes told SINC Reinabelle, lead author of the study published today Nature and researcher at Princeton University.
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A team of astronomers has found the first clear evidence of a binary quasar in a pair of galaxies that are merging to very actively. Quasars are extremely galactic nuclei bright surrounding supermassive black holes and quasars are binary pairs that orbit each other quasars.
Binary quasars, like other quasars, are believed to be the product of merging galaxies. So far, however, no quasar binary had been observed in some galaxy that was unequivocally in the act of merging.
That situation has changed with the images of a captured binary quasar by the Carnegie Institution’s telescope in Chile. These images show two different galaxies with “tails”, produced by the forces Tide of their mutual gravitational attraction.
John Mulchaey, an astronomer at the Carnegie Institute, commented fundamental for the detection of merging galaxies.
Most if not all, large galaxies like our own, the Milky Way harbor a supermassive black hole at their centers. Since the galaxies interact and merge with some regularity, astronomers have assumed that binary black holes supermassive have been common in the universe, especially during the remote past.
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The universe is 13.75 billion years old, confirmed U.S. scientists who predicted that the age of the cosmos using the galaxies as a so-called gravitational lenses. Scientists using this method, also confirmed the value of the Hubble constant, which indicates the speed with which they distance themselves from the individual stars. Information server brought space.com.
So far, the valuation of the Hubble constant used observations of supernovae and monitoring of residual microwave radiation after the big bang. Astrophysicists at Stanford University used to calculate the effect of gravitational lenses and confirmed the values to which it was otherwise. The results confirmed the strength of dark matter, responsible for the accelerated expansion of the universe.
The value of the Hubble constant is by most measurements 72 kilometers per second per megaparsec (megaparsec is 3.26 million light years). This means that every megaparsec distance from Earth, galaxy recedes by 72 kilometers per second.
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