A hydrogen atom is traveling high within the outermost layer of Earth’s atmosphere. This particular atom first entered the exosphere millions of years ago, but today it overcomes Earth’s gravitational pull and escapes, joining the roughly 90 tons of material that leak out of our atmosphere each day. Should we be worried about these leaks? Shannon Odell digs into our planet’s imperfect plumbing. Lesson by Shannon Odell, directed by Eva Münnich, Strange Beast.