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精彩的足球过人,射门集锦：

http://video.google.com/videoplay?docid=-4659497881508632302

http://video.google.com/videoplay?docid=-6063478215160948442

小罗：amazing ronaldinho

http://video.google.com/videoplay?docid=-1483670761495213547

Nature 438, 62-64 (3 November 2005) | doi: 10.1038/nature04205

 A size of 1 AU for the radio source Sgr A* at the centre of the Milky Way

    Zhi-Qiang Shen1, K. Y. Lo2, M.-C. Liang3, Paul T. P. Ho4,5 and J.-H. Zhao4

Although it is widely accepted that most galaxies have supermassive black holes
at their centres1, 2, 3, concrete proof has proved elusive. Sagittarius A* (Sgr
A*)4, an extremely compact radio source at the centre of our Galaxy, is the best
candidate for proof5, 6, 7, because it is the closest. Previous very-long-baseline 
interferometry observations (at 7 mm wavelength) 
reported that Sgr A* is approx2 astronomical units (au) in size8, but this is still
larger than the 'shadow' (a remarkably dim inner region encircled by a bright
ring) that should arise from general relativistic effects near the event horizon
of the black hole9. Moreover, the measured size is wavelength dependent10. Here
we report a radio image of Sgr A* at a wavelength of 3.5 mm, demonstrating that
its size is approx1 au. When combined with the lower limit on its mass11, the
lower limit on the mass density is 6.5 times 1021Mcircle dot pc-3 (where Mcircle
dot is the solar mass), which provides strong evidence that Sgr A* is a
supermassive black hole. The power-law relationship between wavelength and
intrinsic size (sizewavelength1.09) explicitly rules out explanations other than
those emission models with stratified structure, which predict a smaller
emitting region observed at a shorter radio wavelength.

   1. Shanghai Astronomical Observatory, 80 Nandan Road, Shanghai 
200030, China
   2. National Radio Astronomy Observatory, 520 Edgemont Road, 
Charlottesville,
Virginia 22903, USA
   3. Division of Geological and Planetary Sciences, California 
Institute of
Technology, Pasadena, California 91125, USA
   4. Harvard-Smithsonian CfA, 60 Garden Street, Cambridge, 
Massachusetts 02138, USA
   5. Institute of Astronomy & Astrophysics, Academia Sinica, PO Box 
23-141,
Taipei 106, Taiwan, China 

Correspondence to: Zhi-Qiang Shen1 Correspondence and requests for 
materials
should be addressed to Z.-Q.S. (Email: zshen@shao.ac.cn).

Received 1 July 2005; Accepted 31 August 2005

 Sent by odyssey(Jianfeng Zhou, Tsinghua Center for Astrophysics, 
zhoujf@mail.tsinghua.edu.cn)

See paper of :

A CCD Photometric and Morphological Study of the Extended Halo and
Filaments of ESO 383-45: A Galaxy Undergoing Ram Pressure Stripping, or a
Tidal Merger Remnant?
S. N. Kemp, Eduardo de la Fuente, A. Franco-Balderas, and J. Meaburn
Page 680  [ http://www.journals.uchicago.edu/cgi-bin/resolve?ApJ61687 ]