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Seeka
2008-Dec-05, 08:42 PM
Okay so im just starting out i don't know a great deal about astronomy or the universe but one question that always vexes me, How the hell are we here alone!
How is it that our planet is the only one we know of that has life on it? If the universe is so gigantic and theres discoveries being made of other planets each year how can it be its just us. Im looking up at a beautiful half moon and thinking how far man has come, Evolution, the technology available to us, the lifesaving operations we can perform etc and all the while im asking are we really alone?? Also when our sun does burn out will we be so advanced that we will be living elsewhere does anybody think? I was depressed for several days to hear our sun will collapse and we will be sucked in and that will be it for Earth.. I know we won't be around when that happens but still its a horrible thought! Any opinions greatly appreciated:)

NEOWatcher
2008-Dec-05, 08:50 PM
Okay so im just starting out i don't know a great deal about astronomy or the universe but one question that always vexes me, How the hell are we here alone!
We don't know, but the distances, mechanisms and times for communication of any kind of information are so vast that the chances are virtually nil.

How is it that our planet is the only one we know of that has life on it? If the universe is so gigantic...
Yep; it's because the univers is so gigantic. ;)

Imagine in times gone by, some primitive tribe living on an island. No matter how hard they yell; they don't know if someone can hear them. They try to head out away from the island, and either perish along the way, or can only go so far and turn back.
Don't you think they would imagine they were alone, and wonder if there possibly was anyone else out there?

We just don't have the right canoe yet, and even if we do, the nearby islands are deserted.

slang
2008-Dec-05, 09:52 PM
How is it that our planet is the only one we know of that has life on it? If the universe is so gigantic and theres discoveries being made of other planets each year how can it be its just us.

Over 300 planets known, and not a peep from ET yet! Almost all of the planets found so far are somewhat similar to Jupiter. Big balls of gas, most orbiting very close to their suns. This information is in most cases inferred from measurements done to the star they orbit. It's not like we can study the planets themselves in any thorough way yet, we've only just begun to get real pictures of extra solar planets. And those pictures are just dots. No detail. Yet. An incredible accomplishment nonetheless.. 15 years ago we knew not a single extra solar planet.


Im looking up at a beautiful half moon and thinking how far man has come, Evolution, the technology available to us, the lifesaving operations we can perform etc and all the while im asking are we really alone??

I don't know, but it sure is refreshing to hear someone speak this way of what humanity has accomplished, rather than the depressing talk of some others of how bad things are going, with total disregard for the good stuff.


Also when our sun does burn out will we be so advanced that we will be living elsewhere does anybody think? I was depressed for several days to hear our sun will collapse and we will be sucked in and that will be it for Earth..

That time is so far off, that it is completely beyond comprehension for any normal human being. Try to think about a hundred years ago.. that's more difficult to relate to than say 10 years ago. You can remember some previous event in your life, but it's harder to imagine how much time has passed since your great grandmother was born.

Now try a thousand years back. Dark ages. I think for most people it's already starting to become very difficult to get a sense of how much time that is. 20,000 years ago, ice age. A million years ago? 100 million years ago, when the dinosaurs still roamed? How much time is that? I can't make sense of it, in my mind. It keeps coming back just as "an insane amount".

It takes many times that amount of time before really big changes are expected in the sun. Many times an insane amount. It's like taking a teaspoon to the beach, and taking a scoop out of the ocean, throwing it away, and feeling guilty because if you keep doing that the ocean might disappear.

If billions of years from now we still haven't figured out how to get away from the dying sun, we very well will deserve what we get. IMHO. In the meantime, for the next hundred million years, just make the most of life and enjoy it where you can.

[/rant]

Seeka
2008-Dec-05, 10:12 PM
Okay, you guys clearly are making sense and i like your way of conveying idea's as i can relate to them easily. I guess because we are so advanced im almost annoyed we have not made contact with anybody else. :lol: Then again if that actually happened id probably run a mile from anything making contact from outer space!
Is it possible our sun can just collapse any day? Also, when we look at other stars at night, they appear as a silver/blue twinkling ball of light, if we were to get up close would they appear as our own sun providing light, heat etc?

mugaliens
2008-Dec-05, 10:25 PM
I guess because we are so advanced im almost annoyed we have not made contact with anybody else.

Perhaps we already have, but in their primoridal ooze state, they didn't quite fathom the nature of the I Love Lucy rerun washing over them in electromagnetic waves of enlightenment and greeting.

Jeff Root
2008-Dec-05, 11:16 PM
I have no doubt at all that there are lots of other "people" all around
our galaxy, and throughout the Universe. The enormous distances
between stars, and the amount of time and energy required to cross
those distances make interstellar travel depressingly unlikely.

The fact that we have not yet detected any radio or light signals
from other solar systems doesn't mean much. Such signals would
need to be both very powerful and directed exactly toward us for
us to be able to detect them. People living in solar systems a few
tens of light-years away from Earth would be very unlikely to
detect our presence if they were using our equipment. We aren't
putting out that strong a signal in the direction of many places
where someone might be listening.

So much has already been discovered in my lifetime that discovery
of a signal from ET seems like too much to hope for. Maybe in the
next generation, or the generation after that, or the generation
after that, if they have the resources and interest to keep looking.



Is it possible our sun can just collapse any day?
No chance of that. The Sun is gradually going to get hotter over
a period of hundreds of millions of years, though, so our time is
definitely limited, but the Sun will neither collapse nor explode in
that time. The Sun is small enough to have a pretty long lifetime.
Weirdly, the smaller a star, the longer it lasts.



Also, when we look at other stars at night, they appear as a
silver/blue twinkling ball of light, if we were to get up close would
they appear as our own sun providing light, heat etc?
Almost all the stars you can see with just your eyes are larger,
hotter, and brighter than the Sun. That is why they look bluish.
Some stars such as Betelgeuse, Regulus, and Antares are much
larger than the Sun, but cooler, so they are red. Their very large
size makes up for their cooler visible surfaces, so they still look
bright -- just not as intensely bright as blue-white stars.

The majority of stars are smaller, cooler, and much dimmer than
the Sun. You can't see them without binoculars or telescope.
Even the very closest star to us, Proxima Centauri, is too dim to
see without a telescope. Alpha Centauri, close to Proxima and
probably gravitationally connected to it, is about the same size
as the Sun, and the same yellow-white color. Living in the Alpha
Centauri system could be like living in the Solar System. But no
planets have been detected there, so if there are any, they are
probably rather small, and/or far from the star.

-- Jeff, in Minneapolis

creativedreams
2008-Dec-06, 12:31 AM
I am torn between thinking the meeting of other life would be either the most beautiful(5% chance) life discovery or the most horrible(95% chance) life discovery. Just lookiing at our own planet almost everything alive is programmed to attack and kill to survive and promote thier own species. Somehow even plants developed defense mechenisms and some even attack. So sadly I feel there is a 95% chance they wont be friendly.

Neverfly
2008-Dec-06, 12:31 AM
Word on the Galactic Network is that we smell.

Neverfly
2008-Dec-06, 12:33 AM
I am torn between thinking the meeting of other life would be either the most beautiful(5% chance) life discovery or the most horrible(95% chance) life discovery. Just lookiing at our own planet almost everything alive is programmed to attack and kill to survive and promote thier own species. Somehow even plants developed defense mechenisms and some even attack. So sadly I feel there is a 95% chance they wont be friendly.

I can either attack or be friendly.

It depends on whether you approach me politely or if you look like food to me.

creativedreams
2008-Dec-06, 01:09 AM
that is a good perspective

seanhogge
2008-Dec-06, 02:15 AM
What confusion there must be if we ever meet a smiling race of sentient sandwiches.

Neverfly
2008-Dec-06, 02:26 AM
What confusion there must be if we ever meet a smiling race of sentient sandwiches.
They would be very Popplar.

I mean popular.

creativedreams
2008-Dec-06, 02:33 AM
would feel guilty if we meet some talking chickens

Neverfly
2008-Dec-06, 02:45 AM
would feel guilty if we meet some talking chickens

No. I would invite them over for dinner.

Ilya
2008-Dec-06, 03:01 AM
They would be very Popplar.

I mean popular.

No, you mean Poppler (http://www.gotfuturama.com/Information/Encyc-41-Popplers/)

Neverfly
2008-Dec-06, 03:58 AM
Drat.

cran
2008-Dec-06, 09:58 AM
We don't know, but the distances, mechanisms and times for communication of any kind of information are so vast that the chances are virtually nil.

Yep; it's because the univers is so gigantic. ;)

Imagine in times gone by, some primitive tribe living on an island. No matter how hard they yell; they don't know if someone can hear them. They try to head out away from the island, and either perish along the way, or can only go so far and turn back.
Don't you think they would imagine they were alone, and wonder if there possibly was anyone else out there?

We just don't have the right canoe yet, and even if we do, the nearby islands are deserted.
you don't need to go back very far in time to find such people -
not on islands, though - in the isolated high valleys of New Guinea ...
for them, the world ended at the horizon ...
and the horizon was a couple of unclimbable ridges ...
how they got in there in the first place - that's got me puzzled ...
but their world changed when some "pale aliens" (Caucasians) literally dropped in from the clouds (clear sky is rare in that part of the world) ...

we have, in a remarkably few generations, figured out how to start climbing out of our isolated valley ... there's a bigger horizon, and much more journeying ahead ...