... Huge Void Implicated in Distant Universe . ... Credit: Bill Saxton, NRAO , AUI , NSF NASA Explanation: What has created this huge empty area in the universe? ... The void's existence is being postulated following scientific curiosity about how unusually cold spots came to appear on WMAP's map of cosmic microwave background (CMB) radiation. ... An artist's depiction of the huge cosmic void is shown above . ... Cosmic Ripples Implicate Dark Universe . CMB Dipole: Speeding Through the Universe ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2007 August 27 . Huge Void Implicated in Distant Universe . Drawing Credit: Bill Saxton, U. Minnesota , NRAO , AUI , NSF NASA . ... The void's existence is being postulated following scientific curiosity about how unusually cold spots came to appear on WMAP's map of cosmic microwave background (CMB) radiation. ... About APOD | ...

... STScI-PRC01-04 HUBBLE'S ULTRAVIOLET VIEWS OF NEARBY GALAXIES YIELD CLUES TO EARLY UNIVERSE Astronomers are using these three NASA Hubble Space Telescope images to help tackle the question of why distant galaxies have such odd shapes, appearing markedly different from the typical elliptical and spiral galaxies seen in the nearby universe. ... Light from these galaxies travels great distances (billions of light-years) to reach Earth. ... These stars emit mostly ultraviolet light. ...

EMBARGOED UNTIL: 9:20 AM CST, January 6, 1999 CONTACT: John Biretta Space Telecsope Science Institute, Baltimore, MD (Phone: (410) 338-4917; Internet: biretta@stsci.edu) HUBBLE DETECTS FASTER-THAN-LIGHT MOTION IN GALAXY M87 Astronomers reported today discovering clouds which appear to move many times faster than the speed of light, shooting out from the region of a black hole at the center of the M87 galaxy. ... It's an illusion created by the finite speed of light and rapid motion," Biretta said. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Last week's Snack talked about how black holes can affect the environment around them in such a way as to be very bright . ... It's a common misconception that black holes always have matter swirling into them. ... As this matter gets closer and closer to the black hole it piles up and a large, fairly flat disk forms. This is called the accretion disk , because matter from this disk accretes (that is, falls in) on the black hole. ... 2008 Phil Plait. ...

The red colors in this image show the galaxy M66 as it appears at the submillimeter wavelength of 850 microns, while the white background shows the galaxy as it appears in visible light. Regions of cold dust that appear as dark streaks in the white image glow brightly in the red image. ...

Next: Caverns in Binary Systems Up: Ejectors in Massive Binary Previous: The Number of Ejectors . In the very first years after the discovery of radiopulsars, it became clear that for some reason they avoid forming binary systems. ... Illarionov and Sunyaev (1975)[ 76 ] noted the fact that coherent radiowaves with a wavelength longer than 75 cm, which make it possible to observe most of the radiopulsars, are absorbed effectively in the stellar wind of a normal star. ...

Solar Large-Scale Chains: Some Events . ... The chains appear to light up separators or quasi-separatrix layers between different interacting large-scale magnetic flux systems in the global solar magnetosphere and, in particular, to outline large-scale coronal structures involved in the CME process. ... Some features of the chains and their relations to CMEs are illustrated for a number of halo CME-associated events. 23 events of 1997-2000 . ... Halo-CME-associated events of November 1997 . ...

... Circumstellar disc of beta Pictoris: constraints on grain properties from polarization. To appear in the Astronomy & Astrophysics . abs , src , ps ] . ... Dust influx to Titan from Hyperion . ... abs ] . ... Characteristics of bulges and disks in interacting galaxies . ... Dust grains around Herbig Ae/Be stars: porous, cometary-like grains? ... To appear in the Astronomy & Astrophysics Supplement . ... Finally, Links may lead you to more options (e.g. via the LANL preprint system). ...

... Feeding the Monster: Gas Caught in its Death Spiral into a Massive Black Hole . ... Stromlo Professor Mike Dopita have used the Hubble Space Telescope to discover how a massive Black Hole in a nearby galaxy feeds itself. ... Earlier Hubble Telescope data obtained by another team member, Professor Holland Ford of Johns Hopkins University in Baltimore, Maryland, had found a disk of gas rushing around the Black Hole at a speed of 500 kilometers a second. ...

We cannot observe the way the distant universe accelerates cosmic rays or produces energetic photons, but acceleration processes also occur on our Sun , though on a much more moderate scale. ... That is why such events are often missed by cosmic ray detectors near the equator, where the lowest energies are excluded by the Earth's magnetic field. The best detectors for observing solar particles are therefore those sensitive to the lowest energies of the cosmic radiation. ...

... astro-ph . ... Whitespace-separated words are treated as AND ed. Show 10 50 100 articles per page in Full Compact mode . ... Quasar Variability in the Framework of Poissonian Models . ... It is shown that in this very general framework the well established anti-correlation between variability amplitude and wavelength can only be understood as an effect of an underlying spectral component which remains stable on long time-scales, and is redder than the variable component. ...

... The SAS task especget has been designed to allow extraction of source+background and background spectra, redistribution matrices, and effective area vectors from an EPIC event list with a single command. especget can be launched from the main xmmselect window, in which case an extraction region size optimization algorithm is also ran, which maximizes the signal-to-noise of the net source spectrum. ... When you are happy with your definition, click the button 1D region in the xmmselect window. ...

... X-rays are made up of photons that are emitted from stars, or quasars, or supernovae, the sun, or simply: anything that is undergoing a change either in size or temperature or giving out heat. ... in an X-ray binary star system, in which one normal star's orbit is crossed by a neutron star, when the neutron star by means of gravitational pull takes matter from the normal star X-rays form. ... Artists conception of a normal star (HDE 226868) and a black hole taking matter from the normal star. ...

... About ATNF overview . ... Australia Telescope Steering Committee . ... LMC H II Region Luminosities versus . Observed Ionizing Stars . ... These values are compared to the observed H II region luminosities, yielding an estimate for the mean fraction of H-ionizing photons that escape the local nebulae in this sample. We formally estimate that, overall, 0-51% of the ionizing radiation escapes the local H II regions and is available to ionize the warm, ionized medium in the LMC. ...

... Solar System . ... Milky Way . Stars . ... Blue-white Vega is of course one of the brightest stars in our night sky lying about 25 light years from us in Lyra. ... Also in Lyra is the double star Beta Lyrae (Sheliak). This is in fact a close eclipsing pair of B-class stars about 960 light years from the Sun and was only the second eclipsing binary system to be discovered after Algol. ... Planet of Beta Lyrae (from The New Challenge of the Stars by Patrick Moore & David Hardy 1977) . ...

... It was shown in the early 1980's that spectral lines formed around 1-2.5 x 10 5 K were enhanced in radiance by factors up to 15-25 over the normal quiet Sun. From the dynamical viewpoint, this would suggest a pressure imbalance between the sunspot and the surrounding region. ... Here, the electron density was evaluated over a bright sunspot plume region using lines within the O V 760? multiplet. ... The derived densities in all four regions are indicated. ...

... For the past years I have been working on the problem of synthesis of light curves of close binary systems, consisting of a normal star and a compact object (point object with fixed X-ray luminosity). ... Possible existence of a bright spot on the disk's lateral surface is taken into account. ... The last of then will be published in Gordon and Breach Publishers ( Cherepashchuk A.M., Katysheva N.A., Khruzina T.S., Shugarov S.Yu. ... Cherepashchuk A.M., Katysheva N.A., Khruzina T.S., Shugarov S.Yu. ...

Cosmology, Religion & Kansas . ... Cosmology is the study of the origin, current state, and future of our Universe. ... My cosmology tutorial is an attempt to summarize these discoveries. ... These measurements of very small CMB temperature fluctuations over 1% of the sky with a beam size 40 times smaller than COBE's 7 o beam confirm earlier work by a group at Penn & Princeton and data from BOOMERanG's test flight, but provide 3 to 4 times more accuracy. ... Ned Wright's Home Page . ...

Previous section: CCD image processing . ... Figure 6: A small region from a CCD image showing various bad columns. Some pixels are damaged: they cannot transfer the electrons when the image is read out. ... Most telescopes have a 4-legged spider, which produces the typical cross-shaped diffraction pattern visible around the brightest stars. 1-legged spider produces a bar through the star, and some telescopes (like the Keck) have 6-legged spider, so the star images exhibit a 6-legged pattern. ...