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Astronomers No Longer Need To Avoid the "Zone of Avoidance"
An anonymous reader writes: If you want to look out into the Universe, all you need to do is gather the light it gives off. Unless, of course, there's something in the way. For about 20% of the sky, that's exactly the story. In our own Milky Way galaxy, the neutral gas and dust block most of the visible light everywhere we look, preventing us from observing the Universe beyond. However, although the gas and dust might block visible light, longer wavelengths like radio and infrared can pass right through. Recently NASA's Wide-field Infrared Survey Explorer (WISE) mission mapped the entire sky in the infrared, including the entire galactic plane. It not only found many background galaxies, but it gave us a new window into what's possible. Perhaps, with future missions, we'll discover the cause of the "great attractor" phenomenon after all.
now that Forbes blocks Adblockers from proceeding past the stupid splash screen I no longer bother with them, It's nice really that their attempt to protect their advertising revenue has now protected me from their dumb website.
The source
NASA Releases New WISE Mission Catalog of Entire Infrared Sky
http://www.nasa.gov/mission_pa...
WISE Home Page
http://www.jpl.nasa.gov/wise/n...
Link is updated to non Forbes
Astronomers no longer need to avoid...? Really? I'll just point my telescope there and see all the new galaxies now.
If you don't want three levels of dumbing-down, here is the actual study, PDF:
https://www.dropbox.com/s/lp22...
The Parkes HI Zone of Avoidance Survey
Abstract: A blind HI survey of the extragalactic sky behind the southern Milky Way has been conducted with the multibeam receiver on the 64-m Parkes radio telescope. The survey covers the Galactic longitude range 212 degrees to 36 degrees and Galactic latitudes |b| less than 5 degrees to an rms sensitivity of 6 mJy per beam per 27 kmsâ'1 channel, and yields 883 galaxies to a recessional velocity of 12,000 kmsâ'1. The survey covers the sky within the HI Parkes All-Sky Survey (HIPASS) area to greater sensitivity, finding lower HI-mass galaxies at all distances, and probing more completely the large-scale structures at and beyond the distance of the Great Attractor. Fifty-one percent of the HI detections have an optical/near-infrared (NIR) counterpart in the literature. A further 27% have new counterparts found in existing, or newly obtained, optical/NIR 1 images. The counterpart rate drops in regions of high foreground stellar crowding and extinction, and for low-HI mass objects. Only 8% of all counterparts have a previous optical redshift measurement. The HI sources are found independently of Galactic extinction, although the detection rate drops in regions of high Galactic continuum. The survey is incomplete below a flux integral of approximately 3.1 Jy kmsâ'1 and mean flux density of approximately 21 mJy, with 75% and 81% of galaxies being above these limits, respectively. Taking into account dependence on both flux and velocity width, and constructing a scaled dependence on the flux integral limit with velocity width (w0.74), completeness limits of 2.8 Jy kmsâ'1 and 17 mJy are determined, with 92% of sources above these limits. A notable new galaxy is HIZOA J1353â'58, a possible companion to the Circinus galaxy. Merging this catalog with the similarly-conducted northern extension (Donley et al. 2005), large-scale structures are delineated, including those within the Puppis and Great Attractor regions, and the Local Void. Several newly-identified structures are revealed here for the first time. Three new galaxy concentrations (NW1, NW2 and NW3) are key in confirming the diagonal crossing of the Great Attractor Wall between the Norma cluster and the CIZA J1324.7-5736 cluster. Further contributors to the general mass overdensity in that area are two new clusters (CW1 and CW2) in the nearer Centaurus Wall, one of which forms part of the striking 180â--¦ (100hâ'1Mpc) long filament that dominates the southern sky at velocities of â¼ 3000 kmsâ'1, and the suggestion of a further Wall at the Great Attractor distance at slightly higher longitudes.