Chances are the lake closest to you is a freshwater lake. But some lakes are extremely salty. These are called saline lakes. Although freshwater lakes often have minor amounts of dissolved salts in them (less than 1-3 g/L), saline lakes have more than this (between 3 and 300g/L).
Astronomical Unit (A.U.). An astronomical unit (A.U.) is the average distance between the Earth and the Sun, which is about 93 million miles or 150 million kilometers.Astronomical units are usually used to measure distances within our solar system.ne kiloparsec (kpc), is one thousand parsecs. One megaparsec (Mpc) is one million parsecs. SUMMARY 1 Astronomical Unit (A.U.) is the average distance between the Sun and the Earth. 1 A.U. = 93 million miles = 150 million kilometers 1 light-year (ly) is the distance that light travels in one year in a vacuum.
We should like to make a proposal that the average mean distance between the planet Mercury and the Sun be considered for computations of the astronomical unit. The average mean distance between Mercury and the Sun is generally cited as being 36 ,000,000 miles or, 57,900,000 kilometers.weet. The astronomical unit (AU) currently in use is derived from the average mean distance between the Earth and the Sun, which is generally cited as 93 ,000,000 miles or 149,600,000 kilometers.