Help at the Celebrate Memphis Festival OPH Booth

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Greetings Libertarians, This Saturday and Sunday, October 1-2, the Libertarian Parties of Clark and Floyd counties will operate an OPH Booth at the Celebrate Memphis festival. This will be our second time we have had a booth at this event. We will be promoting our local municipal Libertarian Party candidates for public office. We will [...]

Discovery of multiple dust shells beyond 1?arcmin in the circumstellar envelope of IRC?+10216 using Herschel/PACS ?

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Authors: L. Decin, P. Royer, N. L. J. Cox, B. Vandenbussche, R. Ottensamer, J. A. D. L. Blommaert, M. A. T. Groenewegen, M. J. Barlow, T. Lim, F. Kerschbaum, T. Posch and C. Waelkens.<br />Astronomy & Astrophysics Vol. 534 , page A1<br />Published online: 20/09/2011<br />
Keywords:
stars: AGB and post-AGB ; circumstellar matter ; stars: carbon ; stars: individual: IRC +10216.

Spin-orbit measurements and refined parameters for the exoplanet systems WASP-22 and WASP-26???

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Authors: D. R. Anderson, A. Collier Cameron, M. Gillon, C. Hellier, E. Jehin, M. Lendl, D. Queloz, B. Smalley, A. H. M. J. Triaud and M. Vanhuysse.<br />Astronomy & Astrophysics Vol. 534 , page A16<br />Published online: 22/09/2011<br />
Keywords:
binaries: eclipsing ; planetary systems ; stars: individual: WASP-22 ; stars: individual: WASP-26.

Photometric selection of Type Ia supernovae in the Supernova Legacy Survey

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Authors: G. Bazin, V. Ruhlmann-Kleider, N. Palanque-Delabrouille, J. Rich, E. Aubourg, P. Astier, C. Balland, S. Basa, R. G. Carlberg, A. Conley, D. Fouchez, J. Guy, D. Hardin, I. M. Hook, D. A. Howell, R. Pain, K. Perrett, C. J. Pritchet, N. Regnault, M. Sullivan, N. Fourmanoit, S. González-Gaitán, C. Lidman, S. Perlmutter, P. Ripoche and E. S. Walker.<br />Astronomy & Astrophysics Vol. 534 , page A43<br />Published online: 29/09/2011<br />
Keywords:
supernovae: general ; cosmology: observations.

The effect of environment on star forming galaxies at redshift 1 First insight from PACS

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Authors: P. Popesso, G. Rodighiero, A. Saintonge, P. Santini, A. Grazian, D. Lutz, M. Brusa, B. Altieri, P. Andreani, H. Aussel, S. Berta, A. Bongiovanni, A. Cava, J. Cepa, A. Cimatti, E. Daddi, H. Dominguez, D. Elbaz, N. Förster Schreiber, R. Genzel, C. Gruppioni, G. Magdis, R. Maiolino, B. Magnelli, R. Nordon, A. M. Pérez García, A. Poglitsch, F. Pozzi, L. Riguccini, M. Sanchez-Portal, L. Shao, E. Sturm, L. Tacconi, I. Valtchanov, E. Wieprecht and M. Wetzstein.<br />Astronomy & Astrophysics Vol. 534 , page C2<br />Published online: 23/09/2011<br />
Keywords:
galaxies: evolution ; galaxies: star formation ; infrared: galaxies ; errata, addenda.

The diameter of the CoRoT target HD 49933

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Authors: L. Bigot, D. Mourard, P. Berio, F. Thévenin, R. Ligi, I. Tallon-Bosc, O. Chesneau, O. Delaa, N. Nardetto, K. Perraut, Ph. Stee, T. Boyajian, P. Morel, B. Pichon, P. Kervella, F. X. Schmider, H. McAlister, T. ten Brummelaar, S. T. Ridgway, J. Sturmann, L. Sturmann, N. Turner, C. Farrington and P. J. Goldfinger.<br />Astronomy & Astrophysics Vol. 534 , page L3<br />Published online: 29/09/2011<br />
Keywords:
stars: oscillations ; hydrodynamics ; stars: fundamental parameters ; techniques: interferometric ; asteroseismology ; stars: individual: HD 49933.

Arp 220 the Supernova Factory

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Galaxy Arp 220 (main image, taken with the Hubble Space Telescope) with some of its newly discovered supernovae (inset, taken with Global VLBI). The inset image is 250 light years across. Click for larger. Credit: NASA, ESA, Hubble Heritage Team, Chalmers via Spaceref

Arp 220 is what happens when two galaxies merge and it is known to be a prodigious star maker. The name Arp 220 comes from the fact it is listed in Halton Arp’s Atlas of Peculiar Galaxies and that seems to be quite fitting. Aside from the star formation, the presence of organic molecules and now finding that it is quite a “supernova factory”, there is also at least two masers sources in the galaxy: a OH megamaser and a water maser.

Here’s the Onsala press release:

A team led by astronomers at Chalmers and Onsala Space Observatory has detected seven previously unknown supernovae in a galaxy 250 million light years away. Never before have so many supernovae been discovered at the same time in the same galaxy. The results are accepted for publication in the Astrophysical Journal.

The discovery proves what astronomers have long believed: that the galaxies which are the universe’s most efficient star-factories are also supernova factories.

The astronomers used a worldwide network of radio telescopes in five countries, including Sweden, to be able to create extremely sharp images of the galaxy Arp 220. The scientists observed around 40 radio sources in the center of the galaxy Arp 220. These radio sources are hidden behind thick layers of dust and gas and invisible in ordinary telescopes. To discover the nature of these radio sources, they made measurements at different radio wavelengths and watched how they changed over several years.

“With all the data in place, we can now be certain that all seven of these sources are supernovae: stars that exploded in the last 60 years,” says Fabien Batejat, main author of the article about the discovery.

So many supernovae have never before been detected in the same galaxy. The number is nevertheless consistent with how fast stars are forming in Arp 220.

“In Arp 220, we see far more supernovae than in our galaxy. We estimate that a star explodes in Arp 220 once every quarter. In the Milky Way, there is only one supernova per century,” says Rodrigo Parra, astronomer at the European Southern Observatory in Chile and member of the team.

John Conway is professor of observational radio astronomy at Chalmers and deputy director of Onsala Space Observatory.

“Arp 220 is well-known as a place where star formation is very efficient. Now we have been able to show that star factories like this are also supernova factories,” he says.

The radio measurements have also given researchers insight into how radio waves are generated in supernovae and their remnants.

“Our measurements show that a supernova’s own magnetic field is what gives rise to its radio emission, not the magnetic fields in the galaxy around it,” says Fabien Batejat.

Markarian 509

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Hubble's look at the galaxy Markarian 509. Image Credit: NASA, ESA, G. Kriss (STScI), and J. de Plaa (SRON Netherlands Institute for Space Research) Acknowledgment: B. Peterson (Ohio State University) Science Credit: NASA, ESA, J. Kaastra (SRON Netherlands Institute for Space Research), and G. Kriss (STScI)

Hubble’s look at the galaxy Markarian 509.  Click for larger.  Image Credit: NASA, ESA, G. Kriss (STScI), and J. de Plaa (SRON Netherlands Institute for Space Research) Acknowledgment: B. Peterson (Ohio State University) Science Credit: NASA, ESA, J. Kaastra (SRON Netherlands Institute for Space Research), and G. Kriss (STScI)

Here’s the latest offering on Hubblesite, it’s actually a collaboration of four different observatory platforms: ESA’s XMM-Newton and INTEGRAL satellites, NASA’s Chandra X-ray Observatory and of course the Hubble Space Telescope.

For even larger versions than the one above go to Hubblesite, here’s the press release:

SEPTEMBER 29, 2011: An international team of astronomers using five different telescopes has uncovered striking features around a supermassive black hole in the core of the distant galaxy Markarian 509. They found a very hot corona hovering above the black hole and cold gas “bullets” in hotter diffuse gas, speeding outward with velocities over 1 million miles per hour. This corona absorbs and reprocesses the ultraviolet light from the accretion disk encircling the black hole, energizing it and converting it into X-rays.

This discovery allows astronomers to make sense of some of the observations of active galaxies that have been hard to explain so far. The heart of the campaign consisted of repeated visible, X-ray, and gamma-ray observations with ESA’s XMM-Newton and INTEGRAL satellites, which monitored Markarian 509 for six weeks. This was followed by long observations with NASA’s Chandra X-ray Observatory and the Hubble Space Telescope. Prior to these observations short snapshots to monitor the behavior of the source at all wavelengths were taken with NASA’s Swift satellite. The combined efforts of all these instruments gave astronomers an unprecedented insight into the core of an active galaxy.

The Cosmic Origins Spectrograph aboard Hubble reveals that the coolest gas in the line of sight toward Markarian 509 has 14 different velocity components at various locations in the innermost parts of this galaxy. Hubble’s data, combined with X-ray observations, show that most of the visible outflowing gas is blown off from a dusty gas disk surrounding the central region more than 15 light-years away from the black hole. This outflow consists of dense, cold blobs or gas bullets embedded in hotter diffuse gas. The international consortium responsible for this campaign consists of 26 astronomers from 21 institutes on 4 continents. The first results of this campaign will be published as a series of seven papers in the journal Astronomy and Astrophysics. More results are in preparation. For more information about this study, visit:
http://www.sron.nl/index.php?option=com_content&task=view&id=3277&Itemid=754
http://www.spacetelescope.org/announcements/ann1121/