The Lagrange points around celestial bodies is dependent upon the mass of the bodies. The L2 is roughly a million miles away on the far side of the earth in relation to the sun. A smaller body, such as Mars will have Lagrange points at different relative distances than the Earth, as gravity follows the inverse square law.. The properties of the L2 point from the Earth are that the Earth will act as a natural shield against solar radiation and heat, while also allowing for the radiative heat that needs to leave the James Webb in order for it to get down to operational temperatures. The five layers of heat shielding will further allow the instruments aboard to sink, thus costing less as far as necessary payload mass to cool the telescope to its nominal temperature. Idk how closely anyone else has followed this project through the years (decades) of development. I'm incredibly excited about this telescope finally going up and getting the data back that it will provide.