Loading ...
Sorry, an error occurred while loading the content.

Re: Yahoo! News Story - Twin to Milky Way's Black Hole Found - Yahoo! News

Expand Messages
  • mahtezcatpoc
    ... http://news.yahoo.com/s/space/20090126/sc_space/twintomilkywaysblackholefound Twin to Milky Way s Black Hole Found Andrea Thompson Senior Writer SPACE.com
    Message 1 of 2 , Jan 28, 2009
      --- In thefixedstars@yahoogroups.com, Mark Holmes <mahtezcatpoc@...>
      > Mark Holmes (mahtezcatpoc@...) has sent you a news article.
      > (Email address has not been verified.)
      > ------------------------------------------------------------
      > Personal message:
      > Twin to Milky Way's Black Hole Found - Yahoo! News

      Twin to Milky Way's Black Hole Found

      Andrea Thompson
      Senior Writer

      – Mon Jan 26, 10:15 am ET

      A sharp-eyed instrument on the Very Large Telescope has given
      astronomers a peek at the heart of a nearby galaxy, revealing a host
      of young, massive and dusty stellar nurseries and a possible twin of
      our own Milky Way's supermassive black hole.

      The galaxy, dubbed NGC 253, is one of the brightest and dustiest
      spiral galaxies in the sky. It is also known as the Sculptor Galaxy,
      because it is located in the Sculptor constellation.

      The Sculptor Galaxy is a starbust galaxy, so-called because of very
      intense star formation there.

      Astronomers from the Instituto de Astrofísica de Canarias in Spain
      used NACO, an adaptive optics instrument on the European Southern
      Observatory's Very Large Telescope (located in Atacama desert in
      northern Chile), to study NGC 253 in finer detail in the near-infrared.

      Adaptive optics corrects for the blurring effect that Earth's
      atmosphere can have on images taken by ground-based telescopes.
      Sensors and deformable mirrors correct distortions of incoming light,
      producing images as clear as if the telescope were in space.

      With its adaptive optics system, NACO revealed features of NGC 253
      that were only 11 light-years across.

      The NACO observations were combined with data from another VLT
      instrument, VISIR, and images from the Hubble Space Telescope and
      radio observations made by the Very Large Array and the Very Large
      Baseline Interferometer. (Because of their longer wavelengths, radio
      signals aren't affected by atmospheric turbulence.)

      "Our observations provide us with so much spatially resolved detail
      that we can, for the first time, compare them with the finest radio
      maps for this galaxy — maps that have existed for more than a decade,"
      said team member Juan Antonio Fernández-Ontiveros.

      With the images, the astronomers identified 37 distinct bright regions
      — a threefold increase on previous results — packed into a tiny region
      at the core of the galaxy that makes up just 1 percent of the galaxy's
      total size.

      "We now think that these are probably very active nurseries that
      contain many stars bursting from their dusty cocoons," said team
      member Jose Antonio Acosta-Pulido.

      The combined data also led the astronomers to conclude that the center
      of NGC 253 hosts a scaled-up version of Sagittarius A*, the bright
      radio source that lies at the core of the Milky Way and is known to
      harbor a massive black hole.

      "We have thus discovered what could be a twin of our galaxy's center,"
      said team member Almudena Prieto.

      The team's findings are detailed in the January issue of the journal
      Monthly Notices of the Royal Astronomical Society Letters.
    Your message has been successfully submitted and would be delivered to recipients shortly.