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Posts Tagged ‘Big Bang’

First Direct Evidence Of Inflation And Primordial Gravitational Waves


Credit: The BICEP2 Collaboration

Credit: The BICEP2 Collaboration

Astronomers announced today that they have acquired the first direct evidence that gravitational waves rippled through our infant universe during an explosive period of growth called inflation. This is the strongest confirmation yet of cosmic inflation theories, which say the universe expanded by 100 trillion trillion times in less than the blink of an eye.

“The implications for this detection stagger the mind,” says Jamie Bock, professor of physics at Caltech, laboratory senior research scientist at the Jet Propulsion Laboratory (JPL) and project co-leader. “We are measuring a signal that comes from the dawn of time.”

Our universe burst into existence in an event known as the Big Bang 13.8 billion years ago. Fractions of a second later, space itself ripped apart, expanding exponentially in an episode known as inflation. Telltale signs of this early chapter in our universe’s history are imprinted in the skies in a relic glow called the cosmic microwave background. Tiny fluctuations in this afterglow provide clues to conditions in the early universe.

Small, quantum fluctuations were amplified to enormous sizes by the inflationary expansion of the universe. This process created density waves that make small differences in temperature across the sky where the universe was denser, eventually condensing into galaxies and clusters of galaxies. But as theorized, inflation should also produce gravitational waves, ripples in space-time propagating throughout the universe. Observations from the BICEP2 telescope at the South Pole now demonstrate that gravitational waves were created in abundance during the early inflation of the universe.

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Astronomers Observe Distant Galaxy Powered By Primordial Cosmic Fuel

October 4, 2013 Leave a comment

CREDIT: MPIA (G. STINSON / A. V. MACCIÒ)

CREDIT: MPIA (G. STINSON / A. V. MACCIÒ)

Astronomers have detected cold streams of primordial hydrogen, vestigial matter left over from the Big Bang, fueling a distant star-forming galaxy in the early Universe. Profuse flows of gas onto galaxies are believed to be crucial for explaining an era 10 billion years ago, when galaxies were copiously forming stars. To make this discovery, the astronomers – led by Neil Crighton of the Max Planck Institute for Astronomy and Swinburne University – made use of a cosmic coincidence: a bright, distant quasar acting as a “cosmic lighthouse” illuminates the gas flow from behind. The results were published October 2 in the Astrophysical Journal Letters.

The systematic survey of absorption systems comprises observations with the Large Binocular Telescope and from data taken with the W. M. Keck Observatory’s HIRES echelle spectrograph installed on the 10 meter Keck I telescope on the summit of Mauna Kea, Hawaii. The foreground galaxy was discovered by Charles Steidel, Gwen Rudie (California Institute of Technology) and collaborators using the Keck Observatory’s LRIS spectrograph on the same telescope.

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A New Baby Picture Of The Universe


THIS SPRING, HUMANITY WAS SHOWN ITS MOST DETAILED MAP of the early universe ever created. Generated by observations from the Planck spacecraft, the map shows fluctuations in temperature in the relic radiation left over from the Big Bang – the moment when space and time came into existence nearly 14 billion years ago. That relic radiation, a kind of afterglow from the Big Bang, is called the cosmic microwave background, or CMB. It streams toward Earth from everywhere in the sky, and it provides a snapshot of what the universe looked like when the CMB was generated 380,000 years after the Big Bang.

Recently, scientists on the Planck team found certain large-scale features on the CMB sky, which they called “anomalies,” that they cannot explain. One of them, for example, is a large cold spot, which corresponds to an anomalously large area of high density. What this means: the theory for how the universe began may need to be modified, amended or even fundamentally changed. In any of these cases, the result will be consequential to how we understand the evolution of existence.

Full Story: http://www.kavlifoundation.org/science-spotlights/kicc-planck-universe

CSIRO Telescope Takes Temperature Of Universe

January 26, 2013 Leave a comment

Astronomers using a CSIRO radio telescope have taken the Universe’s temperature, and have found that it has cooled down just the way the Big Bang theory predicts.

Using the CSIRO Australia Telescope Compact Array near Narrabri, NSW, an international team from Sweden, France, Germany and Australia has measured how warm the Universe was when it was half its current age.

“This is the most precise measurement ever made of how the Universe has cooled down during its 13.77 billion year history,” said Dr Robert Braun, Chief Scientist at CSIRO Astronomy and Space Science.

According to the Big Bang theory, the temperature of the cosmic background radiation drops smoothly as the Universe expands. “That’s just what we see in our measurements. The Universe of a few billion years ago was a few degrees warmer than it is now, exactly as the Big Bang Theory predicts,” said research team leader Dr Sebastien Muller of Onsala Space Observatory at Chalmers University of Technology in Sweden.

Full Story: http://www.csiro.au/Portals/Media/CSIRO-telescope-takes-temperature-of-Universe

Vast Amounts of Gas & Dust Around Black Hole in Early Universe

March 28, 2012 Leave a comment

Using the IRAM array of millimetre-wave telescopes in the French Alps, a team of European astronomers from Germany, the UK and France have discovered a large reservoir of gas and dust in a galaxy that surrounds the most distant supermassive black hole known. Light from the galaxy, called J1120+0641, has taken so long to reach us that the galaxy is seen as it was only 740 million years after the Big Bang, when the universe was only 1/18th of its current age. Team leader Dr. Bram Venemans of the Max-Planck Institute for Astronomy in Heidelberg, Germany will present the new discovery on Wednesday 28 March at the National Astronomy Meeting in Manchester.

The Institut de Radioastronomie Millimetrique (IRAM) array is made up of six 15-m size telescopes that detect emission at millimetre wavelengths (about ten thousand times as long as visible light) sited on the 2550-m high Plateau de Bure in the French Alps. The IRAM telescopes work together to simulate a single much larger telescope in a so-called interferometer that can study objects in fine detail.

A recent upgrade to IRAM allowed the scientists to detect the newly discovered gas and dust that includes significant quantities of carbon. This is quite unexpected, as the chemical element carbon is created via nuclear fusion of helium in the centres of massive stars and ejected into the galaxy when these stars end their lives in dramatic supernova explosions.

Full Story: http://www.jodrellbank.manchester.ac.uk/meetings/nam2012/pressreleases/nam10.html

New SCUBA-2 Camera Reveals Wild Youth of Universe

March 27, 2012 Leave a comment

A team of astronomers from the UK, Canada and the Netherlands have commenced a revolutionary new study of cosmic star-formation history, looking back in time to when the universe was still in its lively and somewhat unruly youth! The consortium, co-led by University of Edinburgh astrophysicist Professor James Dunlop, is using a brand new camera called SCUBA-2, the most powerful camera ever developed for observing light at “sub-mm” wavelengths (light that has a wavelength 1000 times longer than we can see with our eyes). Prof. Dunlop will present the first results from the survey on Tuesday 27 March at the National Astronomy Meeting in Manchester.

SCUBA-2 is mounted on the world’s largest sub-mm telescope, the 15-metre James Clerk Maxwell Telescope (JCMT), located atop the 4,300-metre high peak of Mauna Kea in Hawaii. The new project, named the SCUBA-2 Cosmology Legacy Survey will run for 3 years and will use the camera to provide the clearest view to date of dust-enshrouded star-forming galaxies. These objects are so remote that the light we detect left them billions of years ago, so we see them as they looked in the distant past. With SCUBA-2 astronomers are able to study objects that existed as far back as 13 billion years ago, within the first billion years after the Big Bang.

Full Story: http://www.jodrellbank.manchester.ac.uk/meetings/nam2012//pressreleases/nam05.html

VISTA Produces Spectacular Panoramic View of the Distant Universe

March 22, 2012 Leave a comment

The most detailed infrared image ever taken of a region of space large enough to be representative of the distant Universe has been released by a team led by the University of Edinburgh. The image from the European Southern Observatory’s (ESO) VISTA telescope reveals more than 200,000 galaxies, including the most distant seen to date in the early Universe. These objects formed less than one billion years after the Big Bang. The new image comes from the first year of data taken as part of the five-year UltraVISTA survey. It was made by combining more than six thousand separate images – equivalent to an exposure time of 55 hours.

The image forms part of a huge collection of fully processed images from all the VISTA surveys that is now being made available by ESO to astronomers worldwide. It comes as a result of the VISTA telescope being trained on the same patch of sky repeatedly to slowly accumulate the very dim light from the most distant galaxies. On this colour composite of the UltraVISTA image, the large white objects with haloes are foreground stars in our own Milky Way Galaxy. A host of other galaxies can be seen, from relatively nearby galaxies which appear large enough to discern their structures, to the most distant galaxies which appear as red dots in this image.
Professor Jim Emerson, of Queen Mary, University of London, Principal Investigator for the construction of VISTA, commented: “These superbly detailed images of such a large area of the distant Universe are an exciting first return for the ten years the team spent getting VISTA from an idea to a successful reality.”

Full Story: http://www.stfc.ac.uk/News+and+Events/38774.aspx

Effect May Bring Universe’s Formation into Sharper Focus

March 20, 2012 2 comments

The first observation of a cosmic effect theorized 40 years ago could provide astronomers with a more precise tool for understanding the forces behind the universe’s formation and growth, including the enigmatic phenomena of dark energy and dark matter.

A large research team from two major astronomy surveys reports in a paper submitted to the journal Physical Review Letters that scientists detected the movement of distant galaxy clusters via the kinematic Sunyaev-Zel’dovich (kSZ) effect, which has never before been seen. The paper was recently posted on the arXiv preprint database, and was initiated at Princeton University by lead author Nick Hand as part of his senior thesis. Fifty-eight collaborators from the Atacama Cosmology Telescope (ACT) and the Baryon Oscillation Spectroscopic Survey (BOSS) projects are listed as co-authors.

Proposed in 1972 by Russian physicists Rashid Sunyaev and Yakov Zel’dovich, the kSZ effect results when the hot gas in galaxy clusters distorts the cosmic microwave background radiation — which is the glow of the heat left over from the Big Bang — that fills our universe. Radiation passing through a galaxy cluster moving toward Earth appears hotter by a few millionths of a degree, while radiation passing through a cluster moving away appears slightly cooler.

Full Story: http://www.princeton.edu/main/news/archive/S33/21/69O40/

Rare Earth Element Found Far, Far Away

February 22, 2012 Leave a comment

Nearly 13.7 billion years ago, the universe was made of only hydrogen, helium and traces of lithium — byproducts of the Big Bang. Some 300 million years later, the very first stars emerged, creating additional chemical elements throughout the universe. Since then, giant stellar explosions, or supernovas, have given rise to carbon, oxygen, iron and the rest of the 94 naturally occurring elements of the periodic table.

Today, stars and planetary bodies bear traces of these elements, having formed from the gas enriched by these supernovas over time. For the past 50 years, scientists have been analyzing stars of various ages, looking to chart the evolution of chemical elements in the universe and to identify the astrophysical phenomena that created them.

Now a team of researchers from institutions including MIT has detected the element tellurium for the first time in three ancient stars. The researchers found traces of this brittle, semiconducting element — which is very rare on Earth — in stars that are nearly 12 billion years old. The finding supports the theory that tellurium, along with even heavier elements in the periodic table, likely originated from a very rare type of supernova during a rapid process of nuclear fusion. The researchers published their findings online in Astrophysical Journal Letters.

Full Story: http://web.mit.edu/press/2012/heavy-metal-stars-tellurium.html

How the Milky Way Killed Off Its Satellites

October 18, 2011 Leave a comment

Two researchers from Observatoire Astronomique de Strasbourg have revealed for the first time the existence of a new signature of the birth of our galaxy’s first stars. More than 12 billion years ago, their intense light dispersed the gas of the Milky Way’s satellite galaxies. By computing the observable consequences of this process, Pierre Ocvirk and Dominique Aubert demonstrated their prevailing role. This result confirms that reionisation is indeed an essential process in the standard model of galaxy formation. The study took place within the LIDAU collaboration (Light In the Dark Ages of the Universe). It is published in the october issue of the letters of the Monthly Notices of the Royal Astronomical Society.

The first stars of the Universe appeared about 150 million years after the Big Bang. Back then, the hydrogen and helium gas filling the universe was cold enough to have its atoms be electrically neutral. As the intense light of the first stars propagated through this gas, it broke the hydrogen atoms, returning them to the plasma state they experienced in the first moments of the Universe. This process, known as reionisation, also results in significant heating, which can have dramatic consequences: the gas becomes so hot that it escapes the weak gravity of the lowest mass galaxies, thereby depriving them of the material needed to form stars. It is now widely admitted that this photo-evaporation process explains the small number and large ages of the stars seen in the dwarf galaxies satellites of the Milky Way. It also offers a credible solution to the missing satellites problem. On the other hand, their sensitivity to UV radiation means satellite galaxies are good probes of the reionisation epoch. Moreover, they are relatively nearby, from 30000 to 900000 light-years, which allows us to study them in great details, especially with the forthcoming generation of telescopes. In particular, the study of their stellar content with respect to their position could give us precious insight into the structure of the local UV radiation field during the reionisation epoch.

Full Story: http://astro.u-strasbg.fr/~ocvirk/PR1.html