July 4, if all goes well, will be an occasion for celebration at NASA as the Juno spacecraft, after a nearly five-year voyage, will go into orbit around Jupiter, the largest planet in the solar system. Juno will spend its time in a zone of intense radiation, against which it has been armored, in an effort to ferret out Jupiter's secrets. By so doing, NASA hopes to gain insights into the origin of the solar system as well as gaining more knowledge of the gas giant, comprised mostly of hydrogen and helium with trace elements of carbon, nitrogen, and sulfur.