from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The apparent change in frequency or wavelength of a wave that is perceived by an observer moving relative to the source of the waves.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. change in the apparent frequency of a wave as observer and source move toward or away from each other
From Johann Christian Andreas Doppler, the scientist who first proposed this effect. (Wiktionary)
If the tampering were done in a pre-space-flight society, anything that far away from us in time would be subject to a Doppler effect of cumulative events.