- Hydrogen is a chemical element; it has the symbol H and atomic number 1. It is the lightest and most abundant chemical element in the universe, constituting about 75% of all normal matter. Under standard conditions, hydrogen is a gas of diatomic molecules with the formula H2, called dihydrogen, or sometimes hydrogen gas, molecular hydrogen, or simply hydrogen. Dihydrogen is colorless, odorless, non-toxic, and highly combustible. Stars, including the Sun, mainly consist of hydrogen in a plasma state, while on Earth, hydrogen is found as the gas H2 (dihydrogen) and in molecules, such as in water and organic compounds. The most common isotope of hydrogen, 1H, consists of one proton, one electron, and no neutrons.
- The Empire Strikes Back (Wikipedia)
The Empire Strikes Back (also known as Star Wars: Episode V – The Empire Strikes Back) is a 1980 American epic space opera film directed by Irvin Kershner from a screenplay by Leigh Brackett and Lawrence Kasdan, based on a story by George Lucas. The sequel to Star Wars (1977), it is the second film in the Star Wars film series and the fifth chronological chapter of the “Skywalker Saga”. Set three years after the events of Star Wars, the film recounts the battle between the malevolent Galactic Empire, led by the Emperor, and the Rebel Alliance, led by Luke Skywalker and Princess Leia. As the Empire goes on the offensive, Luke trains to master the Force so he can confront the Emperor’s powerful disciple, Darth Vader. The ensemble cast includes Mark Hamill, Harrison Ford, Carrie Fisher, Billy Dee Williams, Anthony Daniels, David Prowse, Kenny Baker, Peter Mayhew, and Frank Oz.