Existence of other galaxies?

[umjd]

I am new here. I apologize if this is a ridiculous question. Dammit Jim, I'm a lawyer, not a scientist (perhaps a reference more relatable in this forum ).

 

If the nearest galaxy is about 2.5 million light years away, is it crazy to think that our solar system and galaxy is the only thing and all other galaxies and stars have died out since what we see is an appearance from so long ago. Or is there other evidence that these other galaxies and stars still are in existence, etc. Does that make sense?

Edited July 25, 2012 by umjd

[mathematic]

2.5 million years is a short time for cosmology. Our solar system has been around for about 4.5 billion years.

[alpha2cen]

The reason, we can not see our Galaxy well, is that our Galaxy is very thin. And, we live in there. Time lag is always existence when we see objects in the space. Two factor, observer position and time delay is basically concerned at the astronomy observation. We do not know what is going on that area now. But, the event which is occurring at the present in that galaxy, also delayed effects to us depended on their distance from us.

Edited July 26, 2012 by alpha2cen

[Iota]

Hi there umjd, welcome to the forums.

2.5 million years is a short time for cosmology. Our solar system has been around for about 4.5 billion years.

 

A light year is only a measure of distance though isn't it? At least I've always thought it is. Researched it. It takes 1 year for light to travel that distance- the clue was in the name I guess!

 

 

Or is there other evidence that these other galaxies and stars still are in existence, etc. Does that make sense?

 

Yeah, astrophysicists rely on maths to determine whether or not they still exist. Namely, by calculating how long it has taken for light to reach us from the planet/galaxy/whatever it may be. For e.g., if they find that it takes light 20 minutes to reach us from a distant object in space; we wait 20 minutes, if the object is still there, we know it must still exist, or at least it did 20 minutes ago.

Edited July 26, 2012 by Iota

[Moontanman]

I am new here. I apologize if this is a ridiculous question. Dammit Jim, I'm a lawyer, not a scientist (perhaps a reference more relatable in this forum ).

 

If the nearest galaxy is about 2.5 million light years away, is it crazy to think that our solar system and galaxy is the only thing and all other galaxies and stars have died out since what we see is an appearance from so long ago. Or is there other evidence that these other galaxies and stars still are in existence, etc. Does that make sense?

 

I think is a reasonable question and one I have given some thought to.

 

Science tells us we have pretty good evidence that these phenomena are so long lasting that the 2.5 million years the light takes to get here is very small in comparison to the length of their existence...

 

But it is also true we have no objective way to say they are there right now.... Even our eyesight can be said to be something that happened nano seconds ago. Everything we see is in the past, the sun we see in the sky is really what the sun was like 8 minutes or so ago, Alpha Centaurus is 4.5 years in our past, that galaxy is just 2.5 million years in our past...

[umjd]

Thank you for your thoughts. I guess I don't have a lot to add. I think (and I'm ot even sure) that my point was...people generally say "there must be life in a universe so large". Well, maybe, maybe not. But if everything around is "dead" maybe we are all there is right now.