Beyond the Milky Way Galaxy

[plutonian]

Does any one believe that beyond the Milky Way Galaxy, like in Andromeda perhaps, that there are solar systems like we do here, and well the main question, life? Earth or Earth-like planet(s) that are just like we are?<br />I've always wondered this..

 

[brellis]

Welcome to SDC!<br /><br />Other Galaxies are so far away, all we can do is speculate. In our own Solar System, we're finding a "band" of livable conditions that stretches from the clouds of Venus to the core of Enceladus. As we determine the existence, or even the potential for life in these remote locales, the possibility increases that life can exist elsewhere in the Milky Way. We just launched a 'terrestrial planet-hunter' to help us find rocky, earthlike planets orbiting other stars in the Milky Way. We have a thread here in SDC's Missions & Launches discussing that Mission. <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[sponge]

Hi<br /><br />It would be nice thought to know that there was another whole civilisation/s living next door to us in our neighbouring galaxy, same applies for this galaxy, but unfortunately, the only way we will be able to make contact with them in our life time if they do exist, is if theyre far more advanced than us, and know we are here of course. Because even if we had light speed, it would still take us 4 years to travel to our nearest star Proxima Centauri. Even if theyre not advanced, but somehow we learned of their existence, it would be nice to know we arent the only ones in the nursery.<img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><em><u>SPONGE</u></em></p> </div>

 

[weeman]

Hi Plutonian.<br /><br />I believe there should be other solar systems that can harbor life. If think of the overall chances for planets to exist in the Universe, we can almost conclude that life has to exist somewhere else. <br /><br />Many scientists and religious figures say that Earth and its life are very rare. Well, they're right, the chances of how everything has come to be on Earth are very small. <br /><br />But if we look at the big picture, and consider just how many chances there are for something like Earth to happen, we get a VERY big number.<br /><br />Lets just say that the most common form of galaxy in the Universe is a spiral galaxy. From what humans have discovered in the cosmos, the Milky Way seems to be a very average to somewhat large sized spiral galaxy. So, we might say that the Milky Way is quite an average sized galaxy in the Universe. Just in the Milky Way alone there is some 100 billion stars. Even 100 billion is a HUGE number! And there is an estimated 400 billion galaxies in our observable universe.<br /><br />Astronomers have discovered some 200 planets orbiting other stars. However, since they are at such great distances away, we can't really learn anything about the planets themselves. But if we have discovered 200 planets just on our side of the Milky Way, and the Milky Way is one of hundreds of billions of galaxies, and galaxies contain hundreds of millions to hundreds of billions of stars, then don't you think there would be another Earth out there!? <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[dragon04]

Certainly, even without direct observation, we can be fairly confident that there are solar systems in abundance in the Andromeda galaxy based on the discovery of 177 other solar systems so far here in our own galaxy.<br /><br />Within a decade or so, we should be detecting terrestrial sized planets as well.<br /><br />Life is a much more speculative issue. Once we can resolve terrestrial worlds to spectrographic analysis of their atmospheres (should we find any), we should be able to detect atmospheric components that are markers for life.<br /><br />When or if we find them in our own galaxy, it will be easier to make more competent assumptions about their existence in other galaxies.<br /><br />My guess is that within 25-50 years, we will indeed find rocky worlds with atmospheres similar to our own.<br /><br />Then the process starts all over again. Because we find the atmospheric markers of life does not mean with any certainty that the life is or ever was "intelligent".<br /><br />Having said that, there would be a fair case for life and intelligence to be ubiquitous in the Universe if we find it in our own galaxy.<br /><br />My personal opinion is yes. I'm inclined to believe that there are life bearing planets orbiting stars in not ony M31, but the vast majority of the estimated 2-300 billion galaxies in the Universe. With that many galaxies each containing hundreds of billions of stars each, it seems improbable that there <b>isn't</b> life everywhere.<br /><br />Only science can prove it, though.<br /><br /> <br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[weeman]

<font color="yellow"> Then the process starts all over again. Because we find the atmospheric markers of life does not mean with any certainty that the life is or ever was "intelligent". </font><br /><br />You're right, we wouldn't really know for sure if a planet harbors any intelligent life. I think it would depend on how good the conditions are for life, and how long that planet has had a stable atmosphere. As we have seen here on Earth, life has gone from tiny organisms, to billions of different species. If another planet has had a stable atmosphere and stable conditions for hundreds of millions or billions of years, then we might conclude that life has evolved in the same ways that it has here on Earth.<br /><br />If the very basic life started a few billion years ago, and humans came into the picture a few tens of thousands of years ago, then we might be able to use this time scale to judge whether or not another planet works in the same way. If we find another rocky planet, and somehow date its existence, we might be able to estimate what stages the evolution of life is in.<br /><br />Of course this post depends on the very laws of evolution, assuming it's a real thing <img src="/images/icons/smile.gif" /><br /><br />I for one am a strong believer of evolution. If life started as tiny microorganisms, tiny single-celled life, then how else could it have become the diverse number of species that it is today? Without some type of evolutionary process, how did microbes become fish, birds, apes, elephants, crocodiles, lions, snakes, insects, dogs, cats, humans, etc!? <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[nexium]

I believe, but, I don't know that there is abundant intellgent life, off Earth. We will possibly never have proof regarding other galaxies which are typically millions of times farther away than the closest star (not counting our Sun) in our galaxy. The closest star (not counting our Sun) is about 26 trillion miles away. A trillion is a million multiplied by a million. Neil

 

[qso1]

No real reason I can see not to think other galaxies are similar to ours. Similar shapes, stars, chemical elements...why not solar systems. However, even the nearest galaxy is so far away our chances of ever detecting planets around other stars within those galaxies is remote at best. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[kyle_baron]

<font color="yellow"><br />What are the odds? <br /><br />What happened to form the earth/moon was a rather rare event. A mars sized object struck the earth a glancing blow which did not destroy it or send it out of stable solar orbit. The body shed its iron core, and blew off large amounts of crustal materials so that the lunar density is way lower than the earth's. Those crustal fragments eventually coalesced into the moon, leaving a moon which was composed of the same isotopic stuff as the earth. <br /><br />The odds of that happening are very low, perhaps too low to make the hypothesis credible. At any rate, the creation of the earth/moon system was am exceedingly low probability event, coming as it did within a solar system of a yellow white dwarf star, the sun. As almost all stars are either red dwarves or multiple star systems, this happening in a singleton star system of the right type and stability to allow life to be created, is also a tiny probability. </font><br /><br />I couldn't agree with you more, Steve. Also, did you know that the moon is absolutly necessary to sustain life on earth over the millenia? The moon acts as an anchor to prevent the earth from tipping 90 Deg. on it's axis. It would be similar to the Olympic Hammer Throw, where the person represents the earth and the hammer at the end of a wire represents the moon. This happened on Mars, because it's two moons (really captured asteroids) didn't have enough mass to prevent it's tilt. And if I remember correctly it tilted well over 90 Deg. On Earth that would basically put the equator at the north pole, and extinguishing most, if not all life on the planet. So, the odds are even lower, with a tinier probability of finding intelligent life elsewhere.<br /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>

 

[MeteorWayne]

Maybe the moon is not absoluteley necessary (as other circumstances could have stabilized the earth) but it sure made it easier, and I'm grateful! <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[brellis]

hi steve<br /><br />great post!<br /><br />i have a question from a "cosmoptimistic" (a recently-invented term - i'll update wikipedia <img src="/images/icons/wink.gif" />) viewpoint:<br /><br />in a multiple-star scenario where mature planetary systems collide, would there be more opportunities for collisions on the scale of the one thought to have brought our moon into existence? <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>