Across the Universe

Thomas Mallon has an article in the most recent issue of The Atlantic about solar sailing and The Planetary Society. In the article he interviews Ann Druyan and Louis Friedman.

As friends of Carl Sagan you all are probably familiar with the concept solar sailing, but for those that don't know, here is an excerpt from Mallon:

In March of 2008, I sat down in the carriage house with Friedman and two other members of his solar-sailing team: Harris “Bud” Schurmeier, the retired project manager on the old Voyager missions; and Viktor Kerzhanovich, whose long career in both Russia and America has earned him the U.S.S.R. State Prize and more than one NASA Group Achievement Award. If the Planetary Society tends to exhort its more than 50,000 members in sonorous terms, conversation in the carriage house was speculative and playful. Throughout the morning, the years fell away from the three old-timers eager to tell a visitor about how solar sailing works—and to spar a bit.

“Light has energy,” said Friedman. “That you can’t argue with.”

“More important,” said Kerzhanovich, “it has momentum.”

“Therefore it has a force,” added Friedman. “You’re using the energy of light, and the force derived thereof, to transfer momentum of light energy to your vehicle, in order to propel the spacecraft. Basically your spacecraft, your solar sail, looks like a sail, but it really is a mirror. And so it’s reflecting the light, and that reflection is where the momentum transfer occurs.” If the mirror were fixed to a wall, there would be no transfer. But in free space, with no gravity and no air pressure? You’re off to the cosmic races.

“It’s not the solar wind,” Friedman reminded me.

“Things got named wrong,” said Schurmeier. However pretty it sounds, “sailing” is really a metaphor. There is such a thing as solar wind, but as Friedman explained, “Solar wind is electrons and protons that come from the sun, and they have mass, but they go very much slower than light.”

It’s photons, not protons, that we’re talking about?

“Right,” said Friedman. “Photons have no mass, they’re all energy. You do get a force from the solar wind, but it’s about a thousand times less than the force you get from this reflection. You turn your mirror in different directions, you can point the force in any direction you want!”

You can read the whole article, for free, here.

You can also contribute to The Planetary Society by becoming a member.

Sagan and the Dalai Lama, a Retrospective.

Thanks again go to Larry Klaes for bringing this to our attention.

Religion and science do not have to be at odds. Science, said Ann Druyan, widow of Cornell astronomer Carl Sagan, can communicate with, learn from and even benefit from religion and vice versa.

Druyan, a writer and media producer who collaborated with Sagan for 19 years until his death in 1996, reflected on dialogues in the early 1990s between Sagan and the Dalai Lama at a Sept. 28 lecture in Anabel Taylor Auditorium. For the first time, film excerpts of the meeting between the two were shown in a public venue.

Sagan, Cornell professor and author of "Cosmos," "Contact" and "Dragons of Eden," among other books, was perhaps best known for his extraordinary ability to communicate science to the public. "He wanted to share with everyone the wonder and awe that science inspired in him," Druyan said.

She stressed that there were political motivations behind Sagan's work as well: "Carl believed that you can't have a democratic society if you have a tiny scientific elite and a public who is uncomfortable with the methods and language of science," she said.

Click here to read the whole article from Cornell University's Chronicle Online.

Equal Time for Freethought

Carl Sagan fan and recent addition to the Celebrating Sagan family, Humanistic Joel provided us with this audio a few months ago, and we are proud to finally post here. To learn more about the following episodes of Equal Time for Freethought, or read to the transcripts visit Joel's site. Enjoy.

Little Atoms Radio Show

We produce a radio show in the UK called Little Atoms. We have a special edition commemorating Carl Sagan this Friday 22nd December.

This is the listing for the show:

"The 20th December 2006 marks the tenth anniversary of the death of the astronomer, astrobiologist and populariser of science Carl Sagan. This program will explore aspects of the life, work and influence of Sagan, and includes a number of short interviews with Sagan's family, friends and former colleagues.

Contributors include Ann Druyan, Founder of the Carl Sagan Foundation and wife of Carl's for nearly 20 years until his death. Louis Friedman, co-founder with Sagan and current Executive Director of The Planetary Society, Steven Soter, Research Associate, Department of Astrophysics at the American Museum of Natural History, New York, and collaborator with Sagan on the Emmy award winning television series 'Cosmos: A Personal Journey', Carolyn Porco, Senior Research Scientist at the Space Science Institute in Boulder, Colorado, an Adjunct Professor in the Department of
Planetary Sciences at the University of Arizona, and an Adjunct Professor at the University of Colorado in Boulder, member of the Imaging team on the Voyager missions, and leader of the Cassini-Huygens imaging team, and A.C. Grayling, Professor of Philosophy at Birkbeck College, Rationalist, skeptic and Little Atoms favorite".

The show is an hour long, and is broadcast between 4:30pm and 5:30pm UK time. It will also be available to download from our website Friday morning (UK time again).

Ann Druyan and I talk briefly about the blog-a-thon on the show.

best wishes,

Neil Denny

website: http://www.littleatoms.com
blog: http://little-atoms.blogspot.com/

Honoring Carl.

Ann Druyan

Celebrating Sagan is excited to be working with the public on a series of short articles about Carl Sagan. While we will surely discuss his life and work, most of our writings will be about how Dr. Sagan impacted our lives and perspectives. Simple stuff really -- evangelism in the name of Sagan. Testify!

Since well before his death Carl Sagan was adopted as the public face of science in the United States. Whether Americans know him as a scientific educator on Sesame Street, as a figure being lampooned on Saturday Night Live, or from hosting his monolithic series, Cosmos, the name Carl Sagan has become synonymous with science, space, extra terrestrial life, and an enduring optimism in the human spirit.

These Sagan-esque characteristics have been masterfully captured by Jad Abumrad and Robert Krulwich in a segment they produced for their public radio show, Radio Lab. This touching summation of Carl Sagan's life is told through an interview with his wife, Ann Druyan.

To hear this interview, please listen to the Radio Lab audio clip in the 'Sounds of Sagan' player, located in the sidebar. This interview originally aired on May 12, 2006, as part of a Radio Lab episode on Space. If you enjoy this clip I highly recommend checking out the entire Space episode, or any of Radio Lab's other shows.