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Tinaa
2003-Nov-15, 03:35 AM
Globular clusters in the halo of our galaxy are thought to be very old. What are the chances intelligent life resides out there?

Matthew
2003-Nov-15, 09:38 AM
Less than the chance of there being other intelligent life in the Milky Way. The Milky Way is bigger which means more stars which means more planets ect...

Haglund
2003-Nov-15, 09:47 AM
The stars in these clusters can be so close to each other, I wonder if it is a suitable place for complex life forms at all?

Matthew
2003-Nov-15, 10:05 AM
It would decrese the chance yes, but surely there would be low density areas, of stars.

Haglund
2003-Nov-15, 11:40 AM
Indeed. I'm sure the nightsky would be great too, especially if this cluster is a good way off the Milky Way plane. Would be quite a sight to see our galaxy from a distance.

Planetwatcher
2003-Nov-15, 02:07 PM
I agree the skys would be pretty, but no life.

Dave Mitsky
2003-Nov-15, 02:25 PM
Originally posted by Tinaa@Nov 15 2003, 03:35 AM
Globular clusters in the halo of our galaxy are thought to be very old. What are the chances intelligent life resides out there?
Extremely low since the stars that comprise them are first generation stars with little in the way of heavier elements.

Dave Mitsky

DippyHippy
2003-Nov-16, 03:04 AM
Dave's hit the nail on the head...

Until recently, it was thought to be highly unlikely that globular cluster stars would even have planets because the heavy elements needed weren't so plentiful early on in the universe's (and galaxy's) life... no planets, therefore no life...

However, earlier this year a gas giant was discovered orbiting a star in a globular cluster so even though they might be rare, they do exist. That being the case, maybe there were a few Earth-like planets too...

Tinaa
2003-Nov-16, 03:49 AM
I didn't think of that! Of course we are made of stardust. I was just thinking that if the clusters are supposed to be so old, maybe there is something out there we're missing. How do we know they are all first generation stars? Maybe, there is some kind of interaction with the mysterious dark matter we know nothing about! Is dark matter out around the globular clusters?

lazserus
2004-Jan-01, 05:07 AM
Maybe, there is some kind of interaction with the mysterious dark matter we know nothing about! Is dark matter out around the globular clusters?
Are you insinuating there may be dark matter life forms? I wouldn't get used to entertaining that idea. Even the simplest life needs to consume and output a significant amount of energy, meaning visible matter.

Recent finds are showing quite a few solar systems in our galaxy they are quite similar to our own, but younger. I'm surprised we're finding younger ones as opposed to older ones, since we're the toddlers around here.

Josh
2004-Jan-01, 06:14 AM
Perhaps they emit dark energy?? :P

Littlemews
2004-Jan-01, 10:34 PM
Emit Gamma Ray???? :lol: ????

Tinaa
2004-Jan-02, 04:04 PM
That wasn't quite what I was wondering about. But, now that you've mentioned it, maybe the dark energy to "dark beings" is like sunlight to us. Perhaps, the dark beings cannot look toward us because we are too bright, light hurts their radiation sensors!

VanderL
2004-Jan-02, 04:31 PM
The only way to find out is either go there, or try to find planets. It seems planets can exist around any star, and why shouldn't it be possible to find life as well. The clusters are thought to consist of old (first generation) stars, but we don't know how old they really are. I think the chances of finding life in globular clusters are the same as anywhere else.
Cheers.

lazserus
2004-Jan-02, 11:21 PM
maybe the dark energy to "dark beings" is like sunlight to us.
Dark energy isn't the same kind of energy you're thinking. It's a hypothetical energy that's responsible for the acceleration of the universe's expansion. We've never actually detected this dark energy and new theories are starting to neglect it entirely.

It seems planets can exist around any star
Any stars made up of the heavier elements. Just like Dave said, first generation stars didn't have the heavier elements needed for planetary formation.

I think the chances of finding life in globular clusters are the same as anywhere else.

That all depends on the age of the stars. As well, it depends on how close the stars are to each other. If the stars are too close, then it would be very difficult for any kind of planet to form do to gravitational instability. No planet = No life.

TheThorn
2004-Jan-03, 02:13 AM
Originally posted by Tinaa@Nov 16 2003, 03:49 AM
I didn't think of that! Of course we are made of stardust. I was just thinking that if the clusters are supposed to be so old, maybe there is something out there we're missing. How do we know they are all first generation stars?
We know they're first generation stars by looking at their spectra. No heavy elements. No carbon. No oxygen. No silicon. No iron. No calcium. None of the things that are needed to make life "as-we-know-it". Presumably any planets around such stars have similar composition - hydrogen and helium and precious little else.

Now life "as-we-don't-know-it" (e.g. dark energy kangaroos) might just exist there, but why confine them to globular clusters? They might exist anywhere.

Speculation is so much fun, and inexpensive too.

damienpaul
2004-Jan-05, 11:35 AM
that is very interesting, how many (proportionally) of these stars are there?

Planetwatcher
2004-Jan-05, 04:04 PM
Globular clusters in the halo of our galaxy are thought to be very old. What are the chances intelligent life resides out there?
I believe slim to none, and Slim just left the galaxy.

damienpaul
2004-Jan-05, 11:32 PM
where is slim now?

just what is the proportion of these stars are there in the universe?

TheThorn
2004-Jan-06, 12:23 AM
Originally posted by damienpaul@Jan 5 2004, 11:32 PM
just what is the proportion of these stars are there in the universe?
That's a very good question. I went looking for a source that might give an estimate and couldn't find anything. I found LOTS of sources that describe the difference between Population I and Population II stars. Here's one of the better ones. (http://www.astronomynotes.com/ismnotes/s9.htm)

Pop II are the old "first generation" stars that we're talking about here, but the two "populations" really grade into each other with a full range of intermediaries. Sounds like neither group is rare, but I couldn't find an estimate of the proportions of the two groups.

Perhaps the reason I couldn't find such an estimate is because it would be difficult and pointless to develop one.

Difficult because the brightest stars we see are all young and therefore Pop II, because big bright stars don't live long. All Pop II stars would be dimmer than the sun except for the few that are currently in the red giant stage. Also, since Pop I stars live in the Galactic disk, and Pop II stars live in the halo, nearby stars are mostly Pop I (like the sun). Any astronomer would recognize that both those differences would bias any survey toward over-estimating the proportion of Pop I, so it would be difficult to find ways to account for that bias.

Pointless because there is no clear line between Pop I and Pop II - they form a continuum, not two groups - pick your dividing line and you can make any number come out right.

Or maybe I'm just stupid and the next link I checked would have had it. ;)

Here's a link about an extreme Pop II (http://news.bbc.co.uk/1/hi/sci/tech/2381935.stm) star.

damienpaul
2004-Jan-06, 12:34 AM
thank you for that....i see your point actually, and that extreme star is well - extreme!