## Consequences

The velocity variations have three slightly different origins

- the diurnal variation due to the earth rotation. The maximum value is in 12 hours.
- the yearly variation due to earth orbital motion. The order of magnitude is for two months, with a maximum value of for 6 months
- the source velocity. Typical value is for galactic objects.

Accordingly, the following frequency and velocity differences are induced at 95 GHz USB (harmonic number 50) in the three cases :

- Earth rotation : maximum
- Earth orbit : typical ,
  maximum
- Source to source :

Note that the frequency shifts do not depend on the observing frequency.