“If the sun have been composed of coal, it would very last at the existing charge only 5,000 yrs. The sun, in all chance, is not a burning, but an incandescent, physique. Its gentle is instead that of a glowing molten metallic than that of a burning furnace. But it is unattainable that the sun really should constantly be offering out heat, without possibly getting rid of heat or getting supplied with new gasoline. Assuming that the heat of the sun has been retained up by meteoric bodies slipping into it, it is probable from the mass of the photo voltaic procedure to decide about the period of time during which the sun has shone. The restrictions lie amongst one hundred thousands and thousands and four hundred thousands and thousands of yrs.”
—Scientific American, August 1863
A lot more gems from Scientific American’s initially one hundred seventy five yrs can be identified on our anniversary archive web page.