Sentence:  The results of present observations of the thermal <WSD>radio</WSD> emission of the moon are consistent with the very low thermal conductivity of the surface layer which was derived from the variation in the infrared emission during eclipses ( e.g. , Garstung , 1958 ) . 
Meaning of the word marked with <WSD> tags:  an electromagnetic wave with a wavelength between 0.5 cm to 30,000 m