RMS astronomy

The term RMS astronomy can confuse (see meaning of RMS below), having been used for radio millimeter submillimeter wavelength astronomy, as a collective term for astronomy using EMR frequencies lower than the far infrared, i.e., radio down through its shortest microwave wavelengths into somewhat below a millimeter, thus encompassing radio astronomy, millimeter astronomy, and submillimeter astronomy. The abbreviation has been used in planning efforts and descriptions.

In astronomy, RMS is far more often the abbreviation for root mean square, i.e., the square root of the average/mean of the squares of a set of numbers. This is the common usage of RMS (and rms) in math and science.