Monday, December 1, 2014

Are We Alone In The Milky Way?

Professor Brian Cox (Credit: Manchester University)
BrianCox1
I catch a lot of flack for being negative and condescending to the scientific realm. I blame Milton, he always comes around with a banana, he knows I'm a sucker for bananas. I never know what he is implying, perhaps he is just being nice, bringing the monkey a banana. And then he trashes my fridge, looking for god knows what.

I should embrace being a monkey, it sure gets respect, television shows, movie deals, book deals, and millions of followers. I'm slow, Milton bringing me a banana would have been hint enough for most monkeys.


Lou Baldin    



http://www.forbes.com/sites/paulrodgers/2014/10/31/are-we-alone-in-the-milky-way/
Contributor
Are we alone? Or is the galaxy teeming with other intelligent species? And if the latter, where the heck are they?
These are questions that have perplexed scientists for generations. And they remain open for debate.
But Brian Cox, Britain’s leading celebrity physicist (if you don’t know him, imagine a cross between Neil deGrasse Tyson and pop star Harry Styles) is convinced that we are unique, at least in the Milky Way.
“There is only one advanced technological civilization in this galaxy and there has only ever been one — and that’s us,” Professor Cox, pictured above, declared in the latest episode of his BBC series Human Universe.


His argument, essentially, is that, of the myriad evolutionary paths life could take, most do not lead to intelligence, and he illustrates this by pointing to two pivotal events.
The first was the development of multi-cellular organisms.
We’re so used to a world filled with complex plants and animals that it’s easy to think that nature is all about them.
But single-cell life, such as bacteria, thrived for 2.6 billion years before the first multi-cellular organism evolved. Multi-cellular life was far from inevitable. It was, he argues, a fluke.
“We’re confident this only happened once in the oceans of the primordial Earth.”
His second pivotal event is the extinction of the dinosaurs 65 million years ago, which opened the way for mammals to rise.
Dinosaurs had dominated the planet for nearly 190 million years, 900 times longer than modern humans have existed, without showing any signs of becoming smart.
And they could still be ruling the Earth if a series of unfortunate circumstances hadn’t left them vulnerable to a rare cosmic collision with an asteroid.
Had those dice landed differently, Earth could look totally different today.
Professor Cox’s conclusion, that intelligent life is so unlikely that it can’t have happened twice, comes at a time when many scientists are leaning the other way.
Since PSR B1257+12 B was discovered in 1992, orbiting a pulsar 1,000 light years away in the constellation Virgo, more than 1,800 exoplanets have been found.
And the likelihood of exoplanets — those which orbit other stars — is a crucial factor in the Drake equation.
US astronomer Frank Drake wrote the equation in 1961 at the world’s first Seti meeting in Green Bank, West Virginia.
The equation is:
N = R * fp * ne * fl * fi * fc * L
It says that the number of civilisations capable of sending a signal that could be detected from Earth (N) is equal to the rate of star formation (R) times the fraction of stars that have planets (fp) times the fraction of planets that could support life (ne) times the fraction that do support life (fl) times the fraction that develop intelligent life (fi) times the fraction that develop technologically advanced civilisations (fc) times how long those civilisations survive.
Many scientists, though not presumably Professor Cox, are hopeful that it will eventually yield a result greater than one.
“Do we believe there is life beyond Earth?” former astronaut and Nasa Administrator Charles Bolden said at a Washington conference, according to the Daily Mail.
“I would venture to say that most of my colleagues here today say it is improbable that in the limitless vastness of the universe we humans stand alone.’
Professor Cox has been at pains to emphasise on Twitter since the episode’s broadcast that his limit on alien civilisations applies only to our galaxy, not the whole universe.