A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or coma surrounding the nucleus, and sometimes a tail of gas and dust gas blown out from the coma. These phenomena are due to the effects of solar radiation and the outstreaming solar wind plasma acting upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit. If sufficiently close and bright, a comet may be seen from Earth without the aid of a telescope and can subtend an arc of up to 30° across the sky. Comets have been observed and recorded since ancient times by many cultures and religions.
Philosophiæ Naturalis Principia Mathematica often referred to as simply the Principia, is a book by Isaac Newton that expounds Newton's laws of motion and his law of universal gravitation. The Principia is written in Latin and comprises three volumes, and was authorized, imprimatur, by Samuel Pepys, then-President of the Royal Society on 5 July 1686 and first published in 1687.
Cosmos: A Personal Voyage is a thirteen-part, 1980–81 television series written by Carl Sagan, Ann Druyan, and Steven Soter, with Sagan as presenter. It was executive-produced by Adrian Malone, produced by David Kennard, Geoffrey Haines-Stiles, and Gregory Andorfer, and directed by the producers, David Oyster, Richard Wells, Tom Weidlinger, and others. It covers a wide range of scientific subjects, including the origin of life and a perspective of our place in the universe. Owing to its bestselling companion book and soundtrack album using the title, Cosmos, the series is widely known by this title, with the subtitle omitted from home video packaging. The subtitle began to be used more frequently in the 2010s to differentiate it from the sequel series that followed.
Brannon Braga is an American television producer, director and screenwriter. Best known for his work in the Star Trek franchise, Braga was a key creative force behind three of the franchise's live action series. He later became an executive producer and writer on several Fox shows including 24, Terra Nova, and The Orville. His film credits include Mission: Impossible 2, Star Trek Generations and Star Trek: First Contact.
Neil deGrasse Tyson is an American astrophysicist, author, and science communicator. Tyson studied at Harvard University, the University of Texas at Austin, and Columbia University. From 1991 to 1994, he was a postdoctoral research associate at Princeton University. In 1994, he joined the Hayden Planetarium as a staff scientist and the Princeton faculty as a visiting research scientist and lecturer. In 1996, he became director of the planetarium and oversaw its $210 million reconstruction project, which was completed in 2000. Since 1996, he has been the director of the Hayden Planetarium at the Rose Center for Earth and Space in New York City. The center is part of the American Museum of Natural History, where Tyson founded the Department of Astrophysics in 1997 and has been a research associate in the department since 2003.
Cosmos: A Spacetime Odyssey is a 2014 American science documentary television series. The show is a follow-up to the 1980 television series Cosmos: A Personal Voyage, which was presented by Carl Sagan on the Public Broadcasting Service and is considered a milestone for scientific documentaries. This series was developed to bring back the foundation of science to network television at the height of other scientific-based television series and films. The show is presented by astrophysicist Neil deGrasse Tyson, who, as a young high school student, was inspired by Sagan. Among the executive producers are Seth MacFarlane, whose financial investment was instrumental in bringing the show to broadcast television, and Ann Druyan, a co-author and co-creator of the original television series and Sagan's wife. The show is produced by Brannon Braga, and Alan Silvestri composed the score.
EdmondHalley was an English astronomer, mathematician and physicist. He was the second Astronomer Royal in Britain, succeeding John Flamsteed in 1720.
"Standing Up in the Milky Way" is the first aired episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on March 9, 2014, simultaneously on various Fox television networks, including National Geographic Channel, FX, Fox Life, and others. The episode is presented by the series host astrophysicist Neil deGrasse Tyson, directed by Brannon Braga, produced by Livia Hanich and Steven Holtzman, and written by Ann Druyan and Steven Soter.
"Some of the Things That Molecules Do" is the second episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on March 16, 2014 on Fox.
"A Sky Full of Ghosts" is the fourth episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on March 30, 2014 on Fox and on March 31, 2014 on National Geographic Channel. The episode presented an in-depth treatment of black holes, beginning with John Michell's suggestion of the existence of an "invisible star" to the first discovery of a black hole, Cygnus X-1. The episode's title is an allusion to how light from stars and other cosmic objects takes eons to travel to Earth, giving rise to the possibility that we might be viewing objects that no longer exist.
"Hiding in the Light" is the fifth episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on April 6, 2014 on Fox and aired on April 7, 2014 on National Geographic Channel. The episode explores properties of light, cameras, the scientific method, and the composition of the universe. The episode includes a look at the contributions of the 10th century physicist Ibn al-Haytham, described as the "father of the modern scientific method".
"Deeper, Deeper, Deeper Still" is the sixth episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on April 13, 2014 on Fox and aired on April 14, 2014 on National Geographic Channel. The episode explores the smallest particles in the universe, where host Neil deGrasse Tyson "hunts for elusive neutrinos and the distant, early universe." The episode features the underground neutrino laboratory, Super-Kamiokande, located underneath Mount Kamioka in Japan.
"The Clean Room" is the seventh episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on April 20, 2014, on Fox and aired on April 21, 2014, on National Geographic Channel. The episode explores the methods and processes used to measure the age of the Earth. The episode also pays tribute to geochemist Clair Patterson in his quest to remove the neurotoxin lead, from gasoline. The episode's title alludes to Patterson's attempts in sterilizing his lab after realizing that the inconsistent results in his experiments were due to lead contamination.
"Sisters of the Sun" is the eighth episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on April 27, 2014, on Fox, and aired on April 28, 2014, on National Geographic Channel. The episode explores the violent cosmic phenomenon of supernovas, which on average occur once per galaxy per century or one billion times per year in the observable universe. The episode pays homage to the discoveries of two female astronomers, Cecilia Payne and Annie Jump Cannon, and the obstacles faced by women scientists, especially those working in the early 20th century. Payne discovered the chemical composition of stars and that they consist largely of hydrogen. Cannon developed the first catalog for the spectral characteristics of stars. The episode's title refers to the scientific contributions of the women scientists featured in the episode as well as how their discoveries helped advance our knowledge of the composition of stars.
"The Lost Worlds of Planet Earth" is the ninth episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on May 4, 2014 on Fox, and aired on May 5, 2014 on National Geographic Channel. The episode was directed by Brannon Braga, written by Ann Druyan and Steven Soter, and featured the voice of Amanda Seyfried as geologist Marie Tharp. The episode explores the history of the Earth starting with the period of the Late Heavy Bombardment, approximately "3.8 to 4.1 billion years ago during which the Moon, Mercury, Venus, and the Earth were battered by space debris." Host Neil deGrasse Tyson then delves into the biography of the Earth, expressed "in its continents, oceans and life living on and in them, saying 'the past is another planet,'" alluding to how plate tectonics have shaped the Earth over millions of years.
"The Electric Boy" is the tenth episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on May 11, 2014 on Fox, and aired on May 12, 2014 on National Geographic Channel. The episode was directed by Bill Pope, and written by Ann Druyan and Steven Soter. The episode explores the Earth's magnetic field and the contributions of Michael Faraday, which paved the way for high technology and light-speed communication.
"The Immortals" is the eleventh episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on May 18, 2014, on Fox, and aired on May 19, 2014, on National Geographic Channel. The episode was written by Ann Druyan and Steven Soter, and directed by Brannon Braga. The episode explores the possibility of the interstellar spread of life and possible alien encounters. The episode also presents the hypothesis of panspermia, where the origin of life is attributed to comets or asteroids carrying radiation-resistant organisms.
"The World Set Free" is the twelfth episode of the American documentary television series Cosmos: A Spacetime Odyssey. It premiered on June 1, 2014, on Fox, and aired on June 2, 2014, on National Geographic Channel. The episode was written by Ann Druyan and Steven Soter, and directed by Brannon Braga. The episode explores global warming, humanity's effect on the Earth's atmosphere, and what we can do to mitigate it, including a look at alternative energy technologies. The episode also examines the planet Venus to inspect the runaway greenhouse effect. The episode's title alludes to H. G. Wells' novel published in 1914, The World Set Free, where Wells predicts that humanity will develop destructive nuclear weapons, perpetuating a devastating global war and forcing the world to come to its senses to create a peaceful society that harnesses the power of atomic energy.
"Unafraid of the Dark" is the thirteenth and final episode of the American documentary television series Cosmos: A Spacetime Odyssey and its series finale. It premiered on June 8, 2014, on Fox and aired on June 9, 2014, on the National Geographic Channel. The episode was written by Ann Druyan and Steven Soter, and directed by Ann Druyan, making this her series directorial debut. The episode explores the mysteries of dark energy and dark matter, as well as the contributions and theories of Swiss astronomer Fritz Zwicky, who furthered our understanding of "supernovae, neutron stars and 'standard candles.'" The finale reveals a recording of life on Earth - the final message on the golden record of the space probe, Voyager. The episode ends with Carl Sagan's iconic speech on Earth as the "Pale Blue Dot."
Cosmos: Possible Worlds is a 2020 American science documentary television series that premiered on March 9, 2020, on National Geographic. The series is a follow-up to the 2014 television series Cosmos: A Spacetime Odyssey, which followed the original Cosmos: A Personal Voyage series presented by Carl Sagan on PBS in 1980. The series is presented by astrophysicist Neil deGrasse Tyson, written, directed, and executive-produced by Ann Druyan and Brannon Braga, with other executive producers being Seth MacFarlane and Jason Clark.
