Every second the sun converts roughly 700 million tons of hydrogen into helium. As if by some cosmic magic, the helium weighs less than the original hydrogen. Five million tons less. Matter has been turned into pure energy. E=mc2. Every second the sun turns five million tons of its own substance into radiant energy.
In summer, about a millionth of an ounce of the sun's depleted mass falls each second onto my college campus. In winter less than half as much.
A fraction of a millionth of an ounce of mass is all it takes to ignite the cinnamon ferns by the brook. Like croziers they come up, like cudgels, like Irish shillelaghs, shaking their tight little fists at winter past. In a few days time, with a confident flare, they will unfurl broad sails of chlorophyll, drinking up the sun's red and blue light and leaving the green for the season.