John Locke, a thriller author, decided to self-pub his ebook. One month, he sold 1700 books. The next, he sold 75,000 and then 369,000. He sells them for $.99 so makes about $.35 per book.
You do the math.
Discover the sizzle in science. It's not that stuff that's always for the smart kids. It's the need to know. The passion for understanding. The absolute belief that for every problem, there is a solution. The creative mind seeking truth in a world of mystery. The quest for the Holy Grail.