Content about Astronomy

Feature - Simulating starry images This simulated image of a galaxy cluster is composed of three images of the same area of the sky, measured with different color filters, superimposed to produce a multi-color image. Image courtesy of DES. Ever since the universe exploded into existence, it has been violently rushing outward. Scientists expected the inward tug of gravity to slow this expansion over time, but the opposite is true. The startling discovery that the universe’s expansion is accelerating has led scientists to postulate the existence of an outward-pushing dark energy.To better understand dark energy and its implications on our current knowledge of matter, energy, space, and time, scientists will conduct the large-scale Dark Energy Survey (DES), starting in 2012. Atop a mountain at the Cerro Tololo Inter-American Observatory in Chile, researchers will use the 4-meter Blanco telescope, equipped with the Dark Energy Camera, to capture brilliant images of more than 300 million galaxies. They expect to measure quantiti

Feature - Stargazing in broad daylight Dr. Connie Rockosi, Assistant Professor of Astronomy and Astrophysics at UC Santa Cruz and an Assistant Astronomer at UCO/Lick Observatory, engages theaudience via video-conference. Image courtesy of NCSA. Girls are getting ready for careers in science and mathematics at the National Center for Supercomputing Applications (NCSA) in Urbana, Illinois.The Girls Engaged in Math and Science (GEMS) program at NCSA has partnered for a second year with the Department of Astronomy at the University of Illinois to bring grid-based digital astronomy to about 40 local middle-school girls.  The GEMS program was created in 1994 through a partnership of the Champaign Community Unit School District and NCSA to encourage local girls to consider a wide range of mathematics and science-oriented careers.  Recently, GEMS has turned its focus to astronomy, making use of the largest-ever digital astronomy database, the Sloan Digital Sky Survey (SDSS). The SDSS hosts a public d

Profile - Paola Celio: ARGO, ATLAS and growing the grid Some of the places Paola Celio has been are quite remote, as in the site of the Argo-YBJ gamma-ray detection experiment, located in Tibet, 90 km north of Lhasa.Image courtesy of Paola Celio Paola Celio, like many “grid people,” got her start in particle physics. Now a technical engineer at the Department of Physics at the Roma Tre University, and associated with the Italian National Nuclear Physics Institute, Celio has moved from physics to grid hardware and software, attracted by the tremendous potential of the field. “I started working with grids because I was interested in using something that involves many people, and because it is a field that is evolving very quickly,” Celio explains. “Grids are still in their infancy, but with them we can create a very different future. If we are successful, ultimately the whole scientific community will be able to use grids as just one more tool.”Celio is very keen to pass on her knowledge of grids.

Image of the week - “Little Eyes” of the sky This sky mosaic of the Pleiades, created using grid-enabled Montage software, shows the high-resolution beauty and detail made accessible through the power of grids.Image courtesy of Inseok Song, IPAC/Caltech; created using Montage v3.0Known throughout the world under various names—“Subaru” to the Japanese, Matarii or “Little Eyes” to the natives of Tonga and Athur-ai or “The Stars of Hathor” to the ancient Egyptians—the Pleiades (as it was known to the ancient Greeks) is a cluster of naked-eye stars located in the constellation Taurus, the Bull. This cluster is now known to be a collection of relatively young stars, born only 100 to 125 million years ago. The brightest stars shown here are those visible to the naked eye on a clear winter’s night and represent hot blue giants much more massive than our Sun; the faintest members of the cluster are red dwarfs only a tenth of the Sun’s mass. The blue, green and red cha

Image of the week - LICORICE, photons and the end of the Dark Ages This grid-powered simulation shows radiative transfer of Lyman-alpha photons during the Epoch of Reionization: results that are necessary to compute the hydrogen 21-cm line emissions that will be observed by the future SKA telescope. The box is 2563 particles wide. The color ramp codes the number of Ly-alpha scatterings per atom per second. Image courtesy of Benoit SemelinOnce upon a time, when the Universe was very young and hot, matter existed only as protons and electrons. Then, one day, things cooled off; the ions got together to form neutral atoms.This recombination marked the beginning of what cosmologists call the “Dark Ages of the Universe,” a period of about one billion years for which there is no observational data.Beyond the Dark AgesTowards the end of these Dark Ages, the Universe entered a new phase—the Epoch of Reionization—when UV and X-ray emissions from stars and quasars began to reionize the newly formed neutral atoms. We h

Image of the week - The Water Bearer springs a gas leak The power of grid-enabled Montage software allows astronomers and star-gazers alike to feast their eyes on the Helix nebula in its entirety.Created with IRSA On-Demand Image Mosaic Service and Montage v3.0.The Helix Nebula, also known as NGC 7293, spans a width about half that of the full moon and is located in the constellation Aquarius, the Water Bearer. Although not visible to the unaided eye, a telescopic view, like that shown here, reveals this to be a planetary nebula, one of the closest such nebulae to the Sun. The Helix nebula was created when the central star exhausted its store of hydrogen fuel, causing the star’s core to collapse into a hot remnant—known as a blue subdwarf—and its outer layers to expand into the complex ring of gas and dust seen here. This nebula, because of its immense size on the sky, is difficult to study in its entirety via conventional methods. The image shown here was created using grid-enabled Montage software and encompass

  Feature - Montage a rising star in grid-enabled sky mosaics This mosaic was created using Montage and centers on the dark cloud Barnard 92. The dark clouds cataloged by Barnard contain so much dust that they obscure the light of stars embedded in them and in the line of sight behind them. The clouds thus appear as holes in the sky. Stars become visible as the dust thins out in the periphery of the clouds. Their light assumes a reddish hue because dust grains preferentially extinguish blue light. This is particularly will seen to the west (right) of the cloud. Another dark cloud, Barnard 93, is also seen along the eastern (left) side of the image. The image preserves the positional accuracy and intensities of a total of 92 input images and is an example of the types of images that astronomers use in their research. Image courtesy of Montage Astronomers, like most people, are impressed by pretty pictures, says Bruce Berriman. “We say ‘wow,’ just as the lay public does. But we approach images in a different

Image of the week - MAGIC: low-energy gamma-ray astronomy on a grid MAGIC is characterized by the largest collection surface of any existing gamma-ray telescope world-wide, an assembly of nearly 1000 individual mirrors, together resulting in a parabolic dish of 17 meters diameter.Image courtesy of Robert Wagner, Max-Planck Institute Located on a mountain top on the Canary Island of La Palma, the MAGIC or Major Atmospheric Gamma Imaging Cherenkov telescope records about 500 gigabytes of raw data every night. This data is shuttled via the Enabling Grids for E-sciencE cyberinfrastructure to gamma-ray astronomists from 17 collaborating institutions across nine different countries.EGEE resources also facilitiate more sophisticated analysis of MAGIC data, allowing the MAGIC collaborators to run more complex simulations.The MAGIC-II Datacenter provides storage and access to the experiment data, which is accessible to all collaboration members.The Datacenter also hosts the MAGIC-II Database and an automatic analysis system that serves s

  Feature - Pegasus invites new communities to saddle up This mosaic image of the Orion Nebula was created by Montage using Pegasus and DAGMan tools. Workflow softare Pegasus chains dependent tasks together, so that multiple tasks can be automatically completed in the correct order.  Image courtesy of PegasusGrid workflow system Pegasus recently earned new wings with a share in a US$1.7 million grant from the U.S. Office of CyberInfrastructure, awarded over three years to make further improvements to Pegasus’ usability and breadth of support.Pegasus’ principal investigator, Ewa Deelman from the University of Southern California’s Information Sciences Institute, says the grant has come at the perfect time. “We’re now in a position to work with more communities and more users, including those using Open Science Grid and TeraGrid, to bring Pegasus technologies to their computing work.”Pegasus allows researchers to translate complex computational tasks into workflows that link and manage