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Aliens Are Probably Everywhere, Just Not Anywhere Nearby
rossgneumann writes If there's intelligent life in the cosmos, it's probably nowhere we can get to anytime soon. At least that's the finding of the astrobiologist who, for the first time in decades, has rendered a major update to the key formula scientists use to seek out interstellar life. That'd be the Drake equation, which was developed over half a century ago to determine where life might lurk in the universe. Using the new Kepler data, astrobiologist Amri Wandel did some calculations to estimate the density of life-bearing worlds in our corner of the universe.
I've always felt that the Drake Equation is not worthy of the term 'equation' since its just a simple probabilistic estimate from multiplying a ton of other probabilities and instances together.
It has a term on the left and a term on the right, and an equal sign in between. You can also see the Drake Equation as a Bayesian Network combined with a Poisson estimator for the mean (n*p).
NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
Have a look at http://en.wikipedia.org/wiki/F..., where you see that the Drake equation is a famous example of a Fermi problem, and discussion of errors in Fermi estimations. The goal is to get orders of magnitude, and Fermi problems help to understand where to go for better data, and so they are useful and practical. In this case, the Kepler mission is partly driven by the goal of improving data in the Drake equation to get better estimates.
> 1. There needs to be a planet at an exact distance away from a star so things don't vaporize nor freeze
Which presumes life is based on this temperature range, and not silica or some other process.
> 2. There needs to be water
Again, not mandatory for life. Water-based life, sure. But we have no way of knowing if most life is based on water.
> 3. Atmosphere Oxygen-rich
Again, not mandatory for life. For all we know, oxygen is regarded as a poison by most life.
> 3.5. Atmosphere that isn't toxic
What's toxic for you may not be toxic for most life. Life on gas giants may be quite different, or life in the moons of a gas giant. Oxygen is a fairly toxic gas.
> 4.The Star needs to emit the right amount of energy so not to fry everything.
True. But different life may have different energy ranges. Water has a limited range.
> 5. Planet can't be too close to other stars.
This is most likely the biggest one. Being too close to more than one star means higher range of fluctuation.
> 6. Planet needs to have a core preferably iron to deflect electromagnetic radiation.
Or life exists in gas giants which have thick atmospheres, or beneath the crust.
> 7. Core also keeps ground warm which helps with supporting plant life.
For all we know, perhaps most intelligent life are avian in nature. Birdlike aliens who regard us as crippled freaks.
-- Tigger warning: This post may contain tiggers! --
The birthday paradox depends on days being measured modulo 365. There is a finite bound on the birthdays available. That doesn't extend to planetary distances in three dimensional space over the span of the universe.
I am becoming gerund, destroyer of verbs.
I take it you never heard of that pesky "speed of light" thing? It puts an upper limit to how fast you can go and thanks to us being in the asshole of the Milky way even if we develop craft that run at SOL the distances are so vast that it would take decades to get anywhere good which thanks to time dilation would mean when you got back tens of thousands of years would have passed.
ACs don't waste your time replying, your posts are never seen by me.
So let me see if I got this straight. Less than 300 years ago the fastest method of transportation was horse and buggey and sail ships on the Ocean.
In 300 years we now can put ships in space that can travel at 87,000 mph (143kph), and your best reasoning borrowed from Astrophysicists no less, is that aliens can't be here or make it here because the distances are just too vast ?!?!?
This lacks basic reasoning at minimum and surely imagination.
Imagine if you can how fast we'll be able to travel in space another 300 years from now. Now imagine how fast an alien race could travel if they were 5,000 years more advanced than we are. What about 100,000 years? 1 Million? 10 Million? Pretty sure after even a few thousand years the problem of going across these vast distances will be solved.
Hey, kids, if you extrapolate Moore's "Law" out 25 years, we'll soon be able to make transistors out of 1/40th of an atom! And if you extrapolate the population growth at the start of the 20th century to the current date, all of us are dead of starvation right now (and we didn't even know it)!
It's amazing how the people who have the most faith in science know the least about the actual science.
(Don't bring up wormholes or Alcubierre; both are basically "if we had some materials that violate a whole bunch of laws of physics, we could violate the speed of light limit too. They're bullshit.)
The birthday paradox depends on days being measured modulo 365. There is a finite bound on the birthdays available. That doesn't extend to planetary distances in three dimensional space over the span of the universe.
The whole birthday "paradox" is a human failing of not taking into account the number of possible pairings, it doesn't have to be modulo anything. If you have a thousand planets with life with a one in a million chance to be close, what's the total probabiliy of two planets being close? 1000/1000000? Bzzzzzzt wrong answer, because there's 1000*999/2 = ~500000 possible pairs. So the actual chance is more like 50%, instead of 0,1%. Not that it has any practical application, because it's the odds of two alien planets being close. Earth's chances would still be one in a million per planet, just like the odds of any person having my birthday is roughly 1/365.
Live today, because you never know what tomorrow brings