B3L1U1E1S1H4I1F4T1
17 points
BLUESHIFT is validvalid
the decrease in wavelength of a signal approaching the observer [n BLUESHIFTS]
a shift of the spectrum towards the blue [n -S]
the decrease in wavelength of a signal approaching the observer [n BLUESHIFTS]
a shift of the spectrum towards the blue [n -S]