The file 'AinslieLeighton2016_fig3b_data.txt' contains the data plotted in Figure 3b of Ainslie & Leighton (2016) 'Sonar equations for planetary exploration', J Acoust Soc Am, 
DOI: 10.1121/1.4960786

Figure 3b is a graph of y vs x, where

x = molecular mass, m, in yottograms (yg) for the following liquids [see Table IV for the precise conditions]
row 1 = H2O (Earth)
row 2 = H2O (Europa)
row 3 = C2H6 (Titan)
row 4 = CH4 (Titan)

y = thermal noise coefficient, \mu, in yottograms (yg) for each liquid

\mu / yg	 m / yg		Liquid (see Table IV)
30.160975 	 22.116040 	H2O (Earth)
30.160975 	 18.298575 	H2O (Europa)
50.346400 	 4.329910 		C2H6 (Titan)
26.863688 	 9.818857 		CH4 (Titan)