U.S. CitiesCity-Data Forum Index
Go Back   City-Data Forum > General Forums > Science and Technology > Space
 [Register]
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
View detailed profile (Advanced) or search
site with Google Custom Search

Search Forums  (Advanced)
Reply Start New Thread
 
Old 09-19-2019, 12:55 PM
 
5,210 posts, read 8,210,851 times
Reputation: 3188

Advertisements

Quote:
Originally Posted by Milky Way Resident View Post
I think the situation might be even more dire than that. The nearest known star system is 4 light years away. With current tech it's projected to take 15000 years to reach.
Even if we send probes there, like the ones Stephen Hawking suggested traveling at 0.2c it still amounts to 20 years for a miniscule probe.

Let's say we are able to get humans to the Alpha Centaurus system, how are they expected to keep in touch with the Earth? It would take 4 years to relay that information.
Now imagine they go to a system that's hundreds or thousands of light years away. They would effectively cease to be part of human civilization since they can no longer communicate with the rest of the species. By the time any message comes through, things will have changed dramatically back on Earth that the nation or group that sent them originally may be defunct.

What I'm trying to get across is that even a singular Galaxy is too big to effectively manage. It appears that unless there are multiple civilizations in a singular star system, any species is effectively alone.
I agree with your points. If New Horizons were aimed at Alpha Centauri, it'd take about 78,000 years to get there. As you point out, messaging at the speed of light would take about 4 years one-way. If we called to them, it'd take a minimum of 8 years to hear their reply. Even though it involves long time and distance to communicate, it would be possible to communicate. They would indeed be their own human civilization.

One of the thoughts about travel just to Mars, is that communication takes time to get there and back. Basically, if astronauts have an emergency, they're pretty much on their own. A possible emergency rescue or evacuation plan might be to have a stand-by reserve spacecraft on the surface that's able to launch from Mars and reach Earth. However, there are plenty of emergencies that be impossible to transport people in time to make any difference. Travel between Mars and Earth would take at least months one-way. It could take even longer if the orbits between Mars and Earth are widely distant. The window for launching between Earth and Mars is such that it could take nearly 2 years to reach that window to arrive at Earth in the least amount of time - a trip of about 150-300 days one-way using today's rocket technology. A lot of that has to do with the amount of fuel taken for a trip to Mars. The more fuel carried, the longer it will take. It's conceivable that fuel tanks could be launched into orbit around the Earth, and attached to the spacecraft headed for Mars. That could be pretty complicated. Most likely, the spacecraft at the time of launch would contain all the fuel it needs for the entire round-trip voyage. Some thoughts are to extract water from Mars and convert it into a fuel. If that scenario is considered, it would be better to use remote heavy equipment to do the drilling, extracting, processing and storage long before sending people. That way, they'd have fuel available when they arrive.

If it's that much of a challenge (at the present time) just to go to Mars, it would be an even greater issue to send anyone to the Alpha Centauri system. I think long before such an interstellar mission were to be undertaken, we'd need to be certain there are exoplanets that is actually capable of supporting life, or at least have the resources to be able to survive there.


Quote:
Originally Posted by Milky Way Resident View Post
We will never be able to actually claim that we are alone since we cannot probe the whole universe, our sample size will always be limited. Even if we never find anything, the possibility that life is out there will always remain. I find that beautiful in some ways as it leaves the door open.

If we find conclusive evidence of extraterrestrial life then we solved one of the big mysteries for good, if not, then we keep trying.
Due to the sheer size of the galaxy alone, never mind the entire universe, we might never discover any signs of other intelligent life. Even if it could be done though radio signals, it's entirely likely that understanding such communication might be impossible, without some kind of "Rosetta Stone". Learning a different language here on Earth isn't always the easiest thing to do. Learning the language of an alien civilization far off in the galaxy would be even more difficult, if not impossible. We communicate vocally or through gestures and symbols. What makes anyone think we could understand and communicate with an alien civilization if they don't communicate vocally or symbolically? What if they communicate through various intensities and durations of farting? Different kinds of stink have different meanings.

Personally, I am not optimistic that we would be able to generate radio signals capable of being clearly detected through interstellar space. I think at a certain distance, at least from our own current abilities of transmissions, even though the signals would still be traveling, they might be so weak that it would be drowned out and indistinguishable from all the other static noises in the galaxy. I think the best we'll be able to do to find any kind of life at all, even if its only microbial, dead or alive, would be on Mars. For most people, although it would be an impressive discovery, it wouldn't be that much of a big deal. The real revolutionary discovery would be to discover the presence of highly intelligent life that have technological abilities. Otherwise, the question, "Are we alone?" would remain unanswered.
Reply With Quote Quick reply to this message

 
Old 09-19-2019, 10:41 PM
 
4,264 posts, read 8,019,405 times
Reputation: 6075
The simulation theory helps explain a lot of things.


https://www.youtube.com/watch?v=I_KJKEYoaoo

Last edited by davidt1; 09-19-2019 at 10:50 PM..
Reply With Quote Quick reply to this message
 
Old 09-19-2019, 10:44 PM
 
Location: southern california
56,631 posts, read 75,704,617 times
Reputation: 49520
Its good news for the space aliens
We messed up this planet and are looking to do it some more out there
Reply With Quote Quick reply to this message
 
Old 09-20-2019, 02:59 AM
 
1,294 posts, read 770,118 times
Reputation: 2285
There's no reason to think intelligent life on another planet has to have developed advanced technology when we have people here that have not. They may get everything they need from their environment.
Reply With Quote Quick reply to this message
 
Old 09-21-2019, 02:38 AM
 
12,333 posts, read 3,249,816 times
Reputation: 8207
Quote:
Originally Posted by johnd393 View Post
There's no reason to think intelligent life on another planet has to have developed advanced technology when we have people here that have not. They may get everything they need from their environment.
It would depend on how old their civilization was, look at where we are from a technological standpoint, and we have only been around a couple 1000 yrs...but just imagine what our world will look like 2000 yrs in the future! ( I doubt it would be recognizable to us).
Reply With Quote Quick reply to this message
 
Old 09-22-2019, 10:09 AM
 
Location: Here
1,502 posts, read 371,394 times
Reputation: 5552
Quote:
Originally Posted by Milky Way Resident View Post
I think the situation might be even more dire than that. The nearest known star system is 4 light years away. With current tech it's projected to take 15000 years to reach.
Even if we send probes there, like the ones Stephen Hawking suggested traveling at 0.2c it still amounts to 20 years for a miniscule probe.
I don't think that is an issue. If waiting nine years for New Horizons to get to its destination of a minor planet (Pluto) then I think we'd all happily wait 20 years (plus the four-year lag to receive transmission from the probe showing us what it finds) for an exploration of Alpha Centauri.

The much bigger problem is simply accelerating to 0.2c.

Quote:
Originally Posted by Milky Way Resident View Post
Let's say we are able to get humans to the Alpha Centaurus system, how are they expected to keep in touch with the Earth? It would take 4 years to relay that information.
They would have to be autonomous. But again, that's no great barrier. Magellan's fleet was, the Poynesians exploring the Pacific were, Shackleton was. And a lot of expeditions like those ended with everyone dying. I don't think there will be any shortage of will in both volunteers and organizations if and when it comes to such a mission. Those will be understood and accepted as possible costs.

Quote:
Originally Posted by Milky Way Resident View Post
Now imagine they go to a system that's hundreds or thousands of light years away. They would effectively cease to be part of human civilization since they can no longer communicate with the rest of the species. By the time any message comes through, things will have changed dramatically back on Earth that the nation or group that sent them originally may be defunct.
I doubt you'd ever get that - missions from Earth to a system thousands of light-years away - happening. There are over a quarter million stars within 250ly of Earth, nearly two million within 500ly. That's more than enough subjects for exploration, even when you eliminate the 'uninteresting' ones. I think most exploration would be robotic, with human missions rare, and ultimately only for colonial purposes. Further colonizing would then proceed from established colonies. Of course, the very ability of humanity to ever colonize even one close system remains at this point highly speculative, but if so then those colonies would have to be autonomous in the first place, to communication with Earth would not be essential.

Quote:
Originally Posted by Milky Way Resident View Post
What I'm trying to get across is that even a singular Galaxy is too big to effectively manage. It appears that unless there are multiple civilizations in a singular star system, any species is effectively alone.
I agree that barring superluminal travel - which I think can be discounted - no civilization could ever manage even a small portion of a galaxy. The means of control simply wouldn't be there. As for alone, civilizations in neighboring or relatively near systems - out to, say, a few dozen light-years - could communicate in some fashion, albeit quite delayed. However, the more time passes with no sign of 'anyone' out there, the more the data suggests a minimum average of great distances (thousands or tens of thousands of light-years, or even rarity so great that an individual galaxy will have an average of one or less such entities) between civilizations with communicating potential.
Reply With Quote Quick reply to this message
 
Old 09-22-2019, 10:27 AM
 
Location: Here
1,502 posts, read 371,394 times
Reputation: 5552
Quote:
Originally Posted by johnd393 View Post
There's no reason to think intelligent life on another planet has to have developed advanced technology when we have people here that have not. They may get everything they need from their environment.
Quite so - for each individual body (planet, moon, etc.) that has life.

There's no reason to think that a given species will fly. But some do. There's no reason to think that a given species will have a brain or nurture its young or make/use tools. But some do.

The idea is that X number of planets harbor life, and of those Y number of life-harboring planets have the capacity to develop such technology, and of those planets that do, Z number will be curious enough to probe the skies. In fact, Z seems to follow from Y, as curiosity is a driver of intelligence (intelligence is costly to an organism - not utilizing it is counter-productive, and should be selected against).

So while it is futile to presume actions of a given civilization, it is reasonable to presume that some fraction of what civilizations exist do so. Indeed, from Earth we know that some fraction of planets harbor life, are capable of extraplanetary radio communication, and attempt to engage in said communication. The problem is that, since we haven't the foggiest idea of the actual numbers representing X, Y and Z.
Reply With Quote Quick reply to this message
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.

Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.


Reply
Please update this thread with any new information or opinions. This open thread is still read by thousands of people, so we encourage all additional points of view.

Quick Reply
Message:

Over $104,000 in prizes was already given out to active posters on our forum and additional giveaways are planned!

Go Back   City-Data Forum > General Forums > Science and Technology > Space
Follow City-Data.com founder on our Forum or

All times are GMT -6. The time now is 03:48 PM.

© 2005-2019, Advameg, Inc. · Please obey Forum Rules · Terms of Use and Privacy Policy · Bug Bounty

City-Data.com - Archive 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35 - Top