- #1
trekkiee
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hi, I'm new to this forum and i would like to pose a question that have been bothering me for awhile.
the peak wavelength of the Cosmic Microwave Background (CMB) is lambda_max=[2.898x10^-3 m K]/[2.725 K]=1.06 mm [or 282 GHz], where lambda_max is the maximum, or peak, wavelength, i.e., the wavelength at which the object [the CMB] emits the most energy. lambda_max=[2.898x10^-3 m K]/T is Wien's Law [T is temperature], which applies to blackbody radiation, of which the CMB is about the best example in nature. my confusion arises from trying to find a graph of the spectrum of the CMB which displays this peak wavelength. every graph i find on the web shows the peak at about 2mm, not 1mm. do a google image search of "cosmic microwave background" and u find this image a lot http://en.wikipedia.org/wiki/File:Firas_spectrum.jpg, which clearly peaks close to 2mm [5 waves/cm], not 1mm [10 waves/cm], and u find these images: http://upload.wikimedia.org/wikipedia/commons/5/5c/Cmb_intensity.gif , http://www.rpi.edu/dept/phys/Courses/Astro_F96/lnCMB/cmbSpecData.gif, http://www.symmetrymagazine.org/images/200611/logSM.jpg, http://map.gsfc.nasa.gov/media/ContentMedia/990015b.jpg, http://www.astro.ubc.ca/people/scott/ispectrum.gif, etc. what i find on the net is data, originating almost exclusively from COBE [the cosmic background explorer], i think, displaying peaks near 2mm, 5 waves/cm, or 150 GHz. what i can't find are graphs displaying peaks at 1.06 mm. clearly, I'm missing something relatively simple and obvious here, and i would very much appreciate it if some1 could explain it to me. thanks in advance.
ö¿ö¬ E=mc²
~
the peak wavelength of the Cosmic Microwave Background (CMB) is lambda_max=[2.898x10^-3 m K]/[2.725 K]=1.06 mm [or 282 GHz], where lambda_max is the maximum, or peak, wavelength, i.e., the wavelength at which the object [the CMB] emits the most energy. lambda_max=[2.898x10^-3 m K]/T is Wien's Law [T is temperature], which applies to blackbody radiation, of which the CMB is about the best example in nature. my confusion arises from trying to find a graph of the spectrum of the CMB which displays this peak wavelength. every graph i find on the web shows the peak at about 2mm, not 1mm. do a google image search of "cosmic microwave background" and u find this image a lot http://en.wikipedia.org/wiki/File:Firas_spectrum.jpg, which clearly peaks close to 2mm [5 waves/cm], not 1mm [10 waves/cm], and u find these images: http://upload.wikimedia.org/wikipedia/commons/5/5c/Cmb_intensity.gif , http://www.rpi.edu/dept/phys/Courses/Astro_F96/lnCMB/cmbSpecData.gif, http://www.symmetrymagazine.org/images/200611/logSM.jpg, http://map.gsfc.nasa.gov/media/ContentMedia/990015b.jpg, http://www.astro.ubc.ca/people/scott/ispectrum.gif, etc. what i find on the net is data, originating almost exclusively from COBE [the cosmic background explorer], i think, displaying peaks near 2mm, 5 waves/cm, or 150 GHz. what i can't find are graphs displaying peaks at 1.06 mm. clearly, I'm missing something relatively simple and obvious here, and i would very much appreciate it if some1 could explain it to me. thanks in advance.
ö¿ö¬ E=mc²
~
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