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Why astrophysicist Stephen Hawking is saying we should avoid contact with aliens. We hear the debate from leading scientists.
A new warning from astrophysicist and global science guru Stephen Hawking: Do not talk to aliens.
The brilliant Hawking is wheel-chair bound and speaks through a computer. But he’s thinking about the cosmos.
With billions of galaxies, trillions of stars, the numbers tell him there’s life out there. The smartest forms could make it here. But we should not want that, says Hawking. Too much danger.
Other scientists disagree. We’ll hear that debate, and talk to the man who heads Earth’s greeting committee for aliens.
This Hour, On Point: alien life, and the warning from Stephen Hawking.Guests:
Paul Davies, theoretical physicist, cosmologist, and astrobiologist at Arizona State University. He chairs the SETI Post-Detection Taskgroup, which means he’ll help decide Earth’s response to any first contact with life in space. His new book is “The Eeerie Silence: Renewing Our Search for Alien Intelligence." You can read an excerpt. He runs ASU's Beyond Center for Fundamental Concepts in Science. He wrote in the Wall Street Journal that Stephen Hawking's fears of aggressive aliens are misguided.
Jill Tarter, astronomer who directs the Center for SETI Research and chairs the SETI Institute. The character that Jodi Foster played in the movie “Contact,” which came from Carl Sagan’s novel, was based on Tarter. She served as Project Scientist for NASA’s former SETI program, the High Resolution Microwave Survey. She has conducted observational programs at radio observatories worldwide.
Sean Carroll, theoretical physicist at the California Institute of Technology. He writes for Discover magazine’s “Cosmic Variance” blog – and he wrote recently that Stephen Hawking's fears about aliens may be well-founded. He's author of "From Eternity to Here: The Quest for the Ultimate Theory of Time."
See Stephen Hawking's segment on fearing aliens.
Read astronomer Phil Plait's take on the Hawking debate at his Discover blog, "Bad Astronomy."
Below is the famous plaque, designed by Carl Sagan among others, carried aboard the spacecraft Pioneer 10 and 11. Our guest today Paul Davies has a copy of it on his office wall. In his new book, "The Eerie Silence," he writes, "As a symbolic act, it is a great idea..." But, Davies says, it may be "worthless as far as signalling the aliens" and "[i]t is almost completely irrelevant both scientifically and culturally. To put it bluntly, who gives a damn what we look like?"
What do you make of the image?
Finally, here's the Drake Equation, which is an attempt to formulate the likelihood of other life around the universe:
N = the number of civilizations in our galaxy with which communication might be possible
R* = the average rate of star formation per year in our galaxy
fp = the fraction of those stars that have planets
ne = the average number of planets that can potentially support life per star that has planets
fℓ = the fraction of those planets that actually go on to develop life at some point
fi = the fraction of those planets that actually go on to develop intelligent life
fc = the fraction of those planets on which technological civilization and communication emerges
L = the length of time such civilizations release detectable signals into space.
(Credit: Wikipedia/Paul Davies)
This program aired on April 28, 2010.
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