Painting became an important means of communication for David since his face was slashed during a sword fight and his speech became impeded by a benign tumour that developed from the wound, leading him to stammer. He was interested in painting in a new classical style that departed from the frivolity of the Rococo period and reflected the moral and austere climate before the French Revolution. David became closely aligned with the republican government and his work was increasingly used as propaganda with the Death of Marat proving his most controversial work.

We can't compare anything on earth to the biggest things known in space. The Cosmic Web may connect objects in the universe with threads of Dark Matter. The Lyman-alpha blob is a bubble like structure containing countless galaxies--perhaps the biggest object in the entire universe. Regions of radio-emitting gas called "radio lobes" could be even bigger. Then there are super galaxy clusters which are hundreds of galaxies merged together due to cosmic collisions. Discover which is the largest planet, star, star cluster, constellation, black hole, volcano, galaxy, explosions, moon, storm, impact crater and "void" in space.

Gravity is the most powerful and exacting force in the universe. It is pervasive and penetrating. Gravity binds us together, its reach hangs stars in the sky and its grip crushes light. Gravity holds planets together, and leashes them to their suns. Without gravity, stars, comets, moons, nebulae, and even the Earth itself would not exist. Explore how science and humanity discovered, overcame and utilized gravity. Learn what it takes to propel objects into the heavens, to ride a wave or to ski down a slope. Take a front row seat as an astronaut subjects himself to the weightless wonders of the specially modified aircraft used to train astronauts known as the "Vomit Comet."

Low Earth Orbit, 120 miles above sea level, is where the majority of space exploration has occurred. This 1,100 mile band around Earth is where--for a cool $20 million--any private citizen can take the vacation of his or her life on the International Space Station. Commercial prospects for LEO are huge; but dangers lurk for any individual willing to travel here--radiation, cosmic rays, and space debris numbering in the thousands threaten any spacecraft travelling in orbit. It's the new frontier, or the final frontier...and the possibilities are endless if you are willing to travel to the edge of space exploration.

Beginning with the separation of the fuzzy thinking and pious fraud of astrology from the careful observations of astronomy, Sagan follows the development of astronomical observation. Beginning with constellations and ceremonial calendars (such as those of the Anasazi), the story moves to the debate between Earth and Sun-centered models: Ptolemy and the geocentric worldview, Copernicus' theory, the data-gathering of Tycho Brahe, and the achievements of Johannes Kepler (Kepler's laws of planetary motion and the first science-fiction novel).

Until World War II, Latino immigration to the United States was overwhelmingly Mexican-American. Now three new waves bring large-scale immigration from Puerto Rico, Cuba, and the Dominican Republic. As the Puerto Rican government implements a historic overhaul over a million Puerto Ricans are encouraged to leave for the US mainland, to alleviate the economic pressure. A young Juanita Sanabria arrives in New York, works hard in the garment district, but encounters hostility and discrimination. Ethnic tensions explode in youth gang warfare depicted in films like West Side Story, etching the stereotype of the knife wielding Puerto Rican in the American consciousness.