Our fifth installment of the Cosmos series, Blues for a Red Planet is all about Mars. Like Carl did in the last episode for Venus, he discusses humanity’s fascination with the bright red planet that appears in our night sky. H.G. Wells’ War of the Worlds helped spark this ‘Mars Madness’ around the turn of the century, along with the observations of Shiapperelli
I missed a week last week for no good reason, but here is episode 4 of Cosmos, Heaven and Hell. Carl explores the hells on earth that can come from the heavens in the form of comet and meteor impacts on earth. He speculates on the cause of the Tunguska event in 1908, investigates the history of comet sightings and examines the impacts on our nearest celestial neighbor, the moon. This episode ends with Venus, with its hellish pressures, temperatures and sulfuric acid rain, our visits to the planet, and what Venus has to say about the greenhouse effect here on earth. Enjoy!
For thousands of years, stargazers around the world wondered why there were a handful of lights in the sky that did not follow the motions of all the other lights. Ptolemy in the 2nd century AD came up with the most accurate explanation involving these planets (Greek for wanderers) along with the sun and moon orbiting around the earth, with something called an epicycle to explain why some of the lights sometimes seemed to go backwards in the sky relative to the fixed stars. When the Christian church became the state religion of the Roman empire, this idea, called geocentrism, became widely known and locked into dogma. It wasn’t until the wars of the Reformation that the idea that the Earth along with all the other planets instead orbited around the sun. This idea, written about by a Polish Catholic cleric called Copernicus in Latin, proposed that the planets all followed circular orbits. Copernicus wisely chose to not have his work published until shortly before his death, as questioning dogma was could get you a visit from the inquisition.
But this heliocentric model was actually a less accurate model for the motions of the planets than the existing Ptolemaic geocentric model. It took a protestant monk named Kepler to come up with the solution to this confusion, determining that the planets did orbit the sun, but on elliptical orbits, not circular orbits. And this is what is actually the case. This episode of Cosmos tells Kepler’s story. Enjoy!
Damn, these just give me the chills. Here is the second episode of Cosmos, discussing life in the universe. From the Heiki crab of Japan to the trilobites, from DNA to Miller and Urey, One Voice in the Cosmic Fugue covers the basics of what makes life on earth and wonders what life may be like if it exists elsewhere.
I’m going to start posting Youtube versions of the science series Cosmos, by Carl Sagan, once a week on Sundays. I have this series on DVD, and I’ve watched the entire thing any number of times. I even have the book that covers the entire series. Even after all the times I’ve watched it, Cosmos still gives me that tingly feeling, that feeling of connectedness and immensity that I get when I contemplate the deep mysteries of the universe. The poetry with which Carl narrates, the music that swells and fades in the background, the imagery and scenery disprove the perception that science is cold and distant. This is what inspires me, and keeps me driving onwards to learn more about this wonderful, enormous, complicated and elegant cosmos around us.
This episode is the introduction to the series, beginning with a brief prologue by Carl’s widow, Ann Druyan. The series was originally produced back in 1980. Carl and Ann had updated the series in the 90s to reflect some of advances that had been made in the intervening decade. In addition, a new version of Cosmos is being produced, featuring Neil deGrasse Tyson that is slated to be released in 2013/2014. I am eagerly looking forward to this revamp, and I hope the do justice to Carl’s memory.
I’ll put up a new episode of the series each Sunday until I complete the whole series of 13 hour-long parts. I realize that that’s a long time for anyone to sit and watch a video on their computer, but if you have the time to spare, hopefully Carl can suck you in with his soothing voice. Enjoy!