How is it we can see galaxies light years away?

[recycledpaper]

Originally Posted by Lieutenant Kif

^ well the telescope doesn't really make a difference, since the telescope and your eye are at the same place.

But yes, you are looking at the image of how it existed in the past. How far in the past depends on how many light years away it is.

If a star that is 20 light years away exploded today, and tomorrow wasn't there at all, then 20 years from now you would see all the light from that explosion. 20 years and 1 day from now you would see empty space where the star used to be. But during those 20 years, when the light was in transit, that space would have been empty, we just wouldn't have known it in those 20 years.

so it wouldn't matter if the telescope could look very deep into space to a point where it looks like you're looking at the star as if itwas very close? would you still be looking at it in its past form, or would it simply not be there since you are so "close" to it. sorry if thissounds like a repeat of my first question...

 

[stonedface]

Originally Posted by recycledpaper

Originally Posted by Lieutenant Kif

^ well the telescope doesn't really make a difference, since the telescope and your eye are at the same place.

But yes, you are looking at the image of how it existed in the past. How far in the past depends on how many light years away it is.

If a star that is 20 light years away exploded today, and tomorrow wasn't there at all, then 20 years from now you would see all the light from that explosion. 20 years and 1 day from now you would see empty space where the star used to be. But during those 20 years, when the light was in transit, that space would have been empty, we just wouldn't have known it in those 20 years.

so it wouldn't matter if the telescope could look very deep into space to a point where it looks like you're looking at the star as if it was very close? would you still be looking at it in its past form, or would it simply not be there since you are so "close" to it. sorry if this sounds like a repeat of my first question...

yep still its past form. And I think you'd actually be looking at a black hole.. not empty space

 

[mangudai954]

Originally Posted by doosta45

Originally Posted by StonedFace

you're not looking at the present, but at the past

this

whenever you see a star twinkle, its a galaxy/star that exploded some thousand, million, billion years ago thats finally reaching us

[h1]Why do stars twinkle?[/h1]
The songline goes "Twinkle twinkle little star". What is the cause of the "twinkling" of stars? Does light fromplanets "twinkle" as does light from stars?

A young person of my acquaintance asked me this question, and I didn't have a good answer.

Stars twinkle because of turbulence in the atmosphere of the Earth. As the atmosphere churns, the light from the star isrefracted in different directions. This causes the star's image to change slightly in brightness and position, hence "twinkle." This is one ofthe reasons the Hubble telescope is so successful: in space, there is no atmosphere to make the stars twinkle, allowing a much better image to be obtained.

Planets do not twinkle the way stars do. In fact, this is a good way of figuring out if a particular object you see in the sky is a planet or a star. Thereason is that stars are so far away that they are essentially points of light on the sky, while planets actually have finite size. The size of a planet on thesky in a sense "averages out" the turbulent effects of the atmosphere, presenting a relatively stable image to the eye.

January 1999, Dave Kornreich (more by Dave Kornreich)

 

[flipnkraut]

Either some of you need to lay off the drugs, or go back to science class in elementary/middle school.

 

[recycledpaper]

Originally Posted by FlipnKraut

Either some of you need to lay off the drugs, or go back to science class in elementary/middle school.

 

[tony ayooo]

Originally Posted by Nktran001

I love these kind of topics.

co-signnnnnn

 

[blondsoccerplyr]

Originally Posted by Nktran001

I love these kind of topics.

Me too, because it reveals how poor the education system is in America.

 

[lieutenant kif]

Originally Posted by StonedFace

Originally Posted by recycledpaper

Originally Posted by Lieutenant Kif

^ well the telescope doesn't really make a difference, since the telescope and your eye are at the same place.

But yes, you are looking at the image of how it existed in the past. How far in the past depends on how many light years away it is.

If a star that is 20 light years away exploded today, and tomorrow wasn't there at all, then 20 years from now you would see all the light from that explosion. 20 years and 1 day from now you would see empty space where the star used to be. But during those 20 years, when the light was in transit, that space would have been empty, we just wouldn't have known it in those 20 years.

so it wouldn't matter if the telescope could look very deep into space to a point where it looks like you're looking at the star as if it was very close? would you still be looking at it in its past form, or would it simply not be there since you are so "close" to it. sorry if this sounds like a repeat of my first question...

yep still its past form. And I think you'd actually be looking at a black hole.. not empty space

Not to nitpick but I was just trying to use an easy example to understand, I know stars don't just explode then all traces of it disappear. Not all stars turn into black holes after they die btw.

 

[amazingmrfox]

Originally Posted by recycledpaper

Originally Posted by FlipnKraut

Either some of you need to lay off the drugs, or go back to science class in elementary/middle school.

"NO..."

**jp... couldn't resist...lol**

 

[freshkrn]

Originally Posted by recycledpaper

Originally Posted by FlipnKraut

Either some of you need to lay off the drugs, or go back to science class in elementary/middle school.

Banned!

 

[Nujavez]

its like you're looking back in time when you look at outer space.

 

[amazingmrfox]

Originally Posted by Lieutenant Kif

Originally Posted by StonedFace

Originally Posted by recycledpaper

Originally Posted by Lieutenant Kif

^ well the telescope doesn't really make a difference, since the telescope and your eye are at the same place.

But yes, you are looking at the image of how it existed in the past. How far in the past depends on how many light years away it is.

If a star that is 20 light years away exploded today, and tomorrow wasn't there at all, then 20 years from now you would see all the light from that explosion. 20 years and 1 day from now you would see empty space where the star used to be. But during those 20 years, when the light was in transit, that space would have been empty, we just wouldn't have known it in those 20 years.

so it wouldn't matter if the telescope could look very deep into space to a point where it looks like you're looking at the star as if it was very close? would you still be looking at it in its past form, or would it simply not be there since you are so "close" to it. sorry if this sounds like a repeat of my first question...

yep still its past form. And I think you'd actually be looking at a black hole.. not empty space

Not to nitpick but I was just trying to use an easy example to understand, I know stars don't just explode then all traces of it disappear. Not all stars turn into black holes after they die btw.

@ me only now noticing your SN. Y'all should listen to this guy, he KNOWS a lil about space.

[Zap Brannigan] BTW lieutenant, I'm gonna need you to rub lotion on my lower back...my lower back [/Zap Brannigan]

 

[speakup23]

Originally Posted by blondsoccerplyr

Originally Posted by Nktran001

I love these kind of topics.

Me too, because it reveals how poor the education system is in America.

 

[everydaykicks]

Im too tired for this %+!#

 

[danikerhino]

In simple terms, you are just looking at the light that a galaxy is giving off (heading in our direction).

 

[scotthallwithapick]

What the hell? I always sucked at science. I can balance equations tho

 

[kdawg]

Originally Posted by recycledpaper

Originally Posted by Lieutenant Kif

^ well the telescope doesn't really make a difference, since the telescope and your eye are at the same place.

But yes, you are looking at the image of how it existed in the past. How far in the past depends on how many light years away it is.

If a star that is 20 light years away exploded today, and tomorrow wasn't there at all, then 20 years from now you would see all the light from that explosion. 20 years and 1 day from now you would see empty space where the star used to be. But during those 20 years, when the light was in transit, that space would have been empty, we just wouldn't have known it in those 20 years.

so it wouldn't matter if the telescope could look very deep into space to a point where it looks like you're looking at the star as if it was very close? would you still be looking at it in its past form, or would it simply not be there since you are so "close" to it. sorry if this sounds like a repeat of my first question...

Kif is right - a telescope doesn't actually project into space - you just magnify the image with optics so that you can see smaller things.

The light is still incident on your eye in the same way - and obviously at the same time.

 

[throwedindagame]

Originally Posted by Dips3tRydah


Let's say we look through the hubble telescope back in 1990, wouldn't it take a light year to actually see anything that far? So where are images like this coming from?

the images are X light years old. You are looking at old images....or in NT terms...the images are late
In other words:

If a star is 100 light year away then what you are seeing is actually what the star looked like 100 years ago. Light takes time to travel just like a bullet orcar. The light you are seeing from the stars took a long time to travel...regardless of how far away a star is, the light will eventually reach youreyes/telescope (unless it is absorbed by a black hole).

The telescope is just an extension of your eyes. Focus all you want, it's still positioned on Earth(or in orbit).

 

[beezylocks]

W

W this thread is amazing me

idk if im dum or what but i did not know this stuff

 

[jpioneer]

I always have to hold myself back from thinking about something like this when I'm ++%%%! up because I become very nonsocial

 

[danikerhino]

For all of you that are confused, just think of it as seeing a flashlight's beam from far away at night. You can see it in certain distances, but once youreach a certain point you'll need binoculars. Since it's in the fabric of space, it's easier for us to see bright objects (or reflections) becauseeverything is surrounded by the darkness (the same reason light is easier to see at night).

 

[Coupé It]

awsome thread, but honestly no one really knows whats out there or whats going on out there.

 

[much respected]

lol last time im coming into this thread.. this is just sad.

 

[i am furby]

Originally Posted by StonedFace

Originally Posted by recycledpaper

looking at all those galaxies.. you KNOW there's a place like pandora out there

the only problem is getting there... any NT'ers up to date on space travel technology? any advances that are currently being tested? damn we need to enter the space age!

Whats the point even if space travel technology is getting more advanced, the government will never tell the truth about what they discover out in space, just because they believe society and religion isn't ready to accept extra terrestrial life-forms.

The world as we know it, is the world as we know it, and nothing else, maybe someday we will understand the truth to our existence but not in any of our lifetimes

pretty much sums it up.

 

[danikerhino]

Originally Posted by recycledpaper

looking at all those galaxies.. you KNOW there's a place like pandora out there

the only problem is getting there... any NT'ers up to date on space travel technology? any advances that are currently being tested? damn we need to enter the space age!

Look up Ion Thrusters, way more efficient than chemical rockets. It accelerates ions by bombarding Xenon ( or Argon, Bismuth) with electrons orusing magnets to accelerate the ions out of the thruster at a high rate of speed. It only works in space so far though.