Cosmic Radiation - how is our sun's speed calculated?

[lenfromkits]

From the anisotropic dipole of the CMB, they are able to calculate our velocity through space relative to this radiation. How exactly is this done - in general terms. What assumptions are they needing to make ab out this radiation to deduce our speed from it?

I don't understand the connection between observing the radiation and identifying our speed relative to it.

Thanks!

 

[cepheid]

The connection is basically just the Doppler effect. The radiation will appear blueshifted in the direction of motion and redshifted in the opposite direction. That's why there is a dipole in the first place. This can tell you the velocity relative to a frame of reference in which the radiation appears isotropic (down to a level of one part in 10⁵ of course )

 

[lenfromkits]

The connection is basically just the Doppler effect. The radiation will appear blueshifted in the direction of motion and redshifted in the opposite direction. That's why there is a dipole in the first place. This can tell you the velocity relative to a frame of reference in which the radiation appears isotropic (down to a level of one part in 10⁵ of course )

Oh... I think I'm getting it now. It sounds like you mean they are comparing the frequency of the dipole radiation to the frequency of the non-dipole radiation. The difference in frequency represents the speed at which we are traveling (ie, based on the doppler shift of this frequency that is)?

Thanks for the explanation.