Life in the Universe, Yes or no, maybe?

[Georgi]

Uh, what everyone else said!

Given the size of the universe etc... I'd be surprised if there wasn't.

@Sleep maybe it doesn't apply just to intelligent life being out there, but in regard to aliens actually making contact with us, it would imply that they had far greater technology than we have thus far, because they could travel here etc, and therefore they are probably more intelligent?

[Mr Flibble]

Maybe the earth is just an intergalactic zoo where the creatures all the other aliens don't want to deal with get dumped. And then they come and look at us every now and then. That would at least explain UFO sightings and animals like the platypus.

[Nightmare]

@AN, just adding to your post. This I wrote a while ago, in the Great Questions topic:
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Re on the universe: There was a Time magazine article a while ago that had the latest stuff about the universe.

According to the latest evidence, the universe is full of dark energy (different stuff than of what you, me, the earth, and stars are made up of). According to a pie graph chart in the magazine, this is the amount of matter in the universe (an estimate, of course):
Heavy elements- 0.03%
Neutrinos- 0.3%
Stars- 0.5%
Free hydrogen and helium- 4%
Dark matter- 30%
Dark energy- 65%

According to Einsteinian theory, the universe can take on one of three shapes:

A sphere (positive curvature): We are on the surface of a sphere. Travel far enough and you will return to your original starting point. A triangle will have more than 180 degrees. Without dark energy, it will slow down, stop, and recollapse; with it, expansion will continue.

Flat: You will never return to your starting point. Triangles have pricisely 180 degrees, like in school. Without dark energy, the universe will expand forever, more and more slowly. With it, expansion gets faster. This is the shape of the universe, according to recent observations.

Negative curvature: Travelers never return, triangles have less than 180 degrees. Expansion will barely slow, even without dark energy. Until recently, most evidence favoured this shape.

Whent the big bang happened, something "blew up" from something smaller than a atom in the size of a grapefruit in {10 to the exponent of -32} of a second. Helium, deuterium, and lithium are forged in the first 3 minutes of cosmic history.
Right now, we are about 14 billion years after the big bang. This era of the universe right now, one of young stars, life, and phenomenia, has last since when the universe was a million years old. It will last until 100 trillion years from now.
The next era will range from {10 to the exponent of 14} (100 trillion years) to {10 to the exponent of 45} (10 trillion trillion trillion) years after the big bang. The universe starts expanding exponentially. Planets will detach from stars, and stars will evaporate from galaxies. Almost all stars will die in this era. Over a great deal of time, protons them selves decay.
The next era will range from {10 to the exponent of 45} to {10 to the exponent of 100} years after the big bang. The only larger objects left are balck-holes. They eventually decay into photons and radiation.
The last era will range from {10 to the exponent of 100} years to infinity. Only photons, neutrinos,electrons, and positrons remain, wandering through a universe bigger than the mind a concieve. Electrons and positrons occationaly meet and form "atoms" larger then the visible universe is today. The universe forever remains a cold, dark, and dismal place.

Earth will remain habitable for the next 2-3 billion years, after that, the Sun's brightness and intessaty will have increased so much that the water will boil off the earth. Life cannot survive.
After 5 billion years from now, the Sun will become a red giant, expanding to the size of Venus's orbit. Earth will become completely molten rock. 700 million years later, the sun will fall back down into a white dwarf, no bigger than the earth. The gas giants of our solar system will be featureless blue-green spheres. The Sun will cool to 63 degrees Kelvin. the earth will be 1 degree Kelvin, a single degree above absolute zero.
Six billion years from now, the Andromeda Galxy will collide with the Milky Way, although it is likely no stars will collide (because of the immense amount of space inbetween stars). The new galaxy will now have a gravational pull that will make the white dwarf sun have an elliptical or random orbit in the football shaped galaxy.

[Aegis]

I question our intelligence. When you look at the world, and see how much we have messed it up, it's hard to think of ourselves as being supierior beings.

[Nightmare]

Originally posted by Aegis
I question our intelligence. When you look at the world, and see how much we have messed it up, it's hard to think of ourselves as being supierior beings.

Well, you have a point, but other species from space must have gone through the same thing, IMHO. Why would we be the only race that is violent?

(Perhaps I just misread your post completely, and missed your point)

[Mr Flibble]

@Gaxx, so what's you're saying is that we really aren't that advanced, but simply very good at destroying things, and any civilisation would progress through this stage. I guess that means we've got a long way to go then.

[Nightmare]

Sort of. I'm saying that maybe everyone goes through violence, and it will never quite go away. But still, we do have a ways to go. Can you imagine the chaos there would be, if we discovered aliens/they came to earth, with the weirdos and the religions (a la movie Contact)?

[Aragorn Returns]

you know in the encounters of the third kind movie the government hides from the people that there are aliens to keep all the weirdos and riots and wars from happening.

[AbysmalNature]

The notion that one must abandon all your violent tendencies upon reaching space, or that unification and peace are some type of prequisite for any species which achieves interstellar travel seems more to represent the hope of humans rather then the reality of aliens, the fact of the matter is we know very little about how violent or peaceful aliens will be, they might be hostile, might not be, we must consider both possibilities if we ever go out into space because then we will be dealing with the survival of our species.

Consider this, was our space program birthed in a age of peace as a symbol of cooperation, or in an age of war and competition, not denying the viability of peace just saying it might not necessarily be the right thing when dealing with aliens, even if the best hopes of man turn out right, these hopes might not be entirely accurate when judging a alien lifeform, because I forget the quote the thing about aliens is that they're alien.

Anyway that is just my philosophizing for tonight good night all.

[Aegis]

Our Space program, developed primarly during the space race, which took place dring the Cold War. In our culure/society/history, the only time we make beneficial developments (aside from disease curatives) is during war times, or times of great strife.

[Quark]

Originally posted by Aragorn Returns
exactly, we can be sure there is intelligent life out there because they've never tried to contact us. (i believe there is a quote like this i posted in the "i'm quoting here" thread if someone wants to look it up)

Well, I first saw that in a Calvin and Hobbes collection.

Calvin sees a bunch of trash lying around and says (these are the words I think): "Sometimes I think the surest sign of intelligent life is that none of it has tried to contact us."

[dragon wench]

Or to quote Monty Python,

"Let's hope there's intelligent life elsewhere, because there's bugger all down here"

[VoodooDali]

Here's a review of a book I read. Very compelling--in my gut I disagreed with the authors--mainly because I want there to be other forms of complex life out there.

Rare Earth Punctures Alien Assumptions

By Kenneth Silber

Staff Writer http://www.space.com
posted: 03:10 pm ET
09 February 2000

We may not be alone, but our extraterrestrial neighbors are likely to be bacteria.

In Rare Earth: Why Complex Life is Uncommon in the Universe (Copernicus/Springer-Verlag, $27.50) geologist Peter D. Ward and astronomer Donald Brownlee present a thoughtful, well-argued case that animals (let alone astronomers) are rare and perhaps limited to Earth.

The universe, they note, contains numerous "dead zones," regions in which life seems unlikely. These include the centers of galaxies (too much radiation), the edges of galaxies (not enough elements), and solar systems that have close-in "hot Jupiters" (gas giants that would knock smaller planets into a star).

By contrast, Earth's environs seem unusually benign. Our sun is more massive than most stars, allowing planets to orbit at a safe distance, but doesn’t produce as much dangerous radiation as the most massive stars. Jupiter is well-positioned to divert comets away from Earth. The moon stabilizes our planet's tilt.

Even amid such fortuitous circumstances, Earth has had repeated episodes of mass extinction, the authors point out. The emergence and survival of animal life may have depended on unusual conditions and events, such as ice ages and continental movements that helped ensure a diversity of species.

At the same time, the authors argue, simple organisms such as bacteria -- which arose quite early in Earth's history and survive in environments where animals cannot -- may be commonplace in the cosmos.

To be sure, all this is highly speculative. We know little about the details of the universe's "dead zones" -- for example, there may be habitable moons around hot Jupiters.

And, as Ward and Brownlee acknowledge, our understanding of the forms that life may take is limited by our experience on Earth.

The cold between the stars

Nonetheless, the authors are persuasive, puncturing assumptions that sheer numbers of stars virtually ensure widespread advanced life. They seek, reasonably, to update the Drake Equation, which estimates the number of civilizations in the galaxy, to include such factors as where a star is located in the galaxy.

The authors seem to believe that intelligent life probably exists somewhere else in the galaxy, but their line of reasoning also leaves open the possibility that Earth is, as they put it, "extraordinarily rare." Interestingly, if the authors are wrong about bacterial life, this would strengthen their main argument.

Less convincing, however, is their assertion that the "Rare Earth Hypothesis" gives added reason for protecting endangered animal species on Earth. That's presumably something worth doing in any event.