Latest Big Bang Stories
Weak gravitational lensing is a uniquely promising way to learn how much dark matter there is in the Universe and how its distribution has evolved since the distant past. New work by a team led by a cosmologist from the U.S. Department of Energy's Lawrence Berkeley National Laboratory has made major progress in extending the use of gravitational lensing to the study of much older and smaller structures than was previously possible.Until recently, weak lensing had been limited to calculating...
For more than two decades, the cold dark matter theory has been used by cosmologists to explain how the smooth universe born in the big bang more than 13 billion years ago evolved into the filamentary, galaxy-rich cosmic web that we see today.There's been just one problem: the theory suggested most galaxies should have far more stars and dark matter at their cores than they actually do. The problem is most pronounced for dwarf galaxies, the most common galaxies in our own celestial...
Scientists have made many discoveries about the origins of our 13 billion-year-old universe. But many scientific mysteries remain. What exactly happened during the Big Bang, when rapidly evolving physical processes set the stage for gases to form stars, planets and galaxies? Now astrophysicists using supercomputers to simulate the Big Bang have a new mathematical tool to unravel those mysteries, says Daniel R. Reynolds, assistant professor of mathematics at SMU.Reynolds collaborated with...
Astronomers, using NASA's Hubble Space Telescope, have broken the distance limit for galaxies by uncovering a primordial population of compact and ultra-blue galaxies that have never been seen before. They are from 13 billion years ago, just 600 to 800 million years after the Big Bang.These newly found objects are crucial to understanding the evolutionary link between the birth of the first stars, the formation of the first galaxies, and the sequence of evolutionary events that resulted in...
NASA's Hubble Space Telescope has broken the distance limit for galaxies and uncovered a primordial population of compact and ultra-blue galaxies that have never been seen before.The deeper Hubble looks into space, the farther back in time it looks, because light takes billions of years to cross the observable universe. This makes Hubble a powerful "time machine" that allows astronomers to see galaxies as they were 13 billion years ago, just 600 million to 800 million years after...
The Universe's infant galaxies enjoyed rapid growth spurts forming stars like our sun at a rate of up to 50 stars a year, according to scientists at Durham University.The findings show that "stellar nurseries" within the first galaxies gave birth to stars at a much more rapid rate than previously expected, the researchers from Durham's Institute for Computational Cosmology revealed. Their work appears in a paper in the journal Monthly Notices of the Royal Astronomical Society.The research...
Astronomers, conducting the broadest survey to date of galaxies from about 800 million years after the Big Bang, have found 22 early galaxies and confirmed the age of one by its characteristic hydrogen signature at 787 million years post Big Bang. The finding is the first age-confirmation of a so-called dropout galaxy at that distant time and pinpoints when an era called the reionization epoch likely began. The research will be published in a December issue of the Astrophysical Journal.With...
A detailed picture of the seeds of structures in the universe has been unveiled by an international team co-led by a Cardiff University scientist.The team has obtained extremely precise data about the early universe, using a telescope near the South Pole in the Antarctic.Their measurements of the cosmic microwave background - a faintly glowing relic of the hot, dense, young universe - provide further support for the standard cosmological model of the universe. The findings confirm the model's...
 As scientists attempt to learn more about how galaxies evolve, an open question has been whether collisions with our dwarf galactic neighbors will one day tear apart the disk of the Milky Way.That grisly fate is unlikely, a new study now suggests.While astronomers know that such collisions have probably occurred in the past, the new computer simulations show that instead of destroying a galaxy, these collisions "puff up" a galactic disk, particularly around the edges, and produce...
An international group of scientists says it has defined the energy density of gravitational waves created immediately after the birth of the universe.Gravitational waves that still ripple across the universe are believed to result from the Big Bang that created the universe more than 13 billion years ago. Albert Einstein predicted the existence of the waves in 1916, and the first evidence of their existence was reported in 1979.Scientists from the Laser Interferometer Gravitational-Wave...
Latest Big Bang Reference Libraries
Image Caption: The Hubble Extreme Deep Field (XDF) was completed in September 2012 and shows the farthest galaxies ever photographed by humans. Each speck of light in the photo is an individual galaxy, some of them as old as 13.2 billion years; the observable universe is estimated to contain more than 200 billion galaxies. Credit: NASA/Wikipedia What is Cosmology? I once commented to an acquaintance that I was fascinated by the field of Cosmology, and mused that if I had more time, I...
Large-Scale Structure of the Cosmos -- Stars are organised into galaxies which in turn appear to form clusters and superclusters, separated by voids. Prior to 1989 it was commonly assumed that the superclusters were the largest structures in existence, and that they were distributed more-or-less uniformly throughout the universe in every direction. However, in 1989, Margaret Geller and John Huchra discovered the "Great Wall", a sheet of galaxies more than 500 million light years long...
Cosmology -- area of science that aims at a comprehensive theory of the structure and evolution of the entire physical universe. Modern Cosmological Theories Present models of the universe hold two fundamental premises: the cosmological principle and the dominant role of gravitation. Derived by Hubble, the cosmological principle holds that if a large enough sample of galaxies is considered, the universe looks the same from all positions and in all directions in space. The second point...
Redshift -- Redshift is the phenomenon that the frequency of light when observed, under certain circumstances, can be lower than the frequency of light when it was emitted at the source. This usually occurs when the source moves away from the observer, as in the Doppler effect. More specifically, the term redshift is used for the observation that the spectrum of light emitted by distant galaxies is shifted to lower frequencies (towards the red end of the spectrum, hence the name) when...
Quasar -- A quasar (from quasi-stellar radio source) is an astronomical object that looks like a star in optical telescopes (i.e. it is a point source), but has a very high redshift. The general consensus is that this high redshift is cosmological, the result of Hubble's law and that their redshift indicates that they are typically very distant from Earth; we observe them as they were several billions of years ago. Since we can see them despite their distance, they must emit more...
