The Hubble Deep Field

[maverickeastwood]

The religious context was used as an example, nothing more.

[evman150]

I apologize...I get on a thought and can't stop!

[maverickeastwood]

eh, it happens.

[Cheese]

Here is another very cool video from a Japanese lunar explorer, Kaguya.

As opposed to watching the Moon or Sun rise we have "The Earth Rise".

[worth]

The 78b number is the radius of the universe, so the diameter is 156 billion light years across.

Was a head scratcher when I first read that. The universe is only 13.7b years old. That is when the big bang took place and the universe was formed. So according to Special Relativity, nothing can travel beyond the speed of light, so really the universe should only have a radius of 13.7b light years and a diameter of 27.4b light years.

I guess it's kind of a technicality that the universe is expanding rapidly, so really nothing has violated special relativity, yet the universe is much bigger than anyone would have really conceived using todays physics.

And yes, the farther away you look, the more "back in time" you are looking. Light only travels so fast. Interesting to think that a star we see in pictures may not even exist anymore.

[metal_geek]

Hubble is awesome, and has provided some really astounding images... Hubble is like the famous model who gets all the attention at a fashion show. It takes 100's of people to design, make and plan the models 15 seconds of fame. The model is all the public sees in the magazines and the model gets most of the recognition.

Most of the scientific data used to make discovery's and even data used to add the detail to the Hubble pictures come from other telescopes both space and earth based. The Spitzer and Galex scopes do Equally AMAZING things and very few people have ever heard about them. Even earth based telescopes can take pictures close to what Hubble can, given the time and money, although nothing can really compare on earth to what Hubble can see in the UV range...

I'm gonna be sad to see Hubble burn up over the pacific when it does, but the James Webb space telescope is gonna fun to see in action, and hopefully Hubble's fame can be shared equally all the systems up there.
________
VAPOLUTION VAPORIZER

[photon]

Originally Posted by worth

The 78b number is the radius of the universe, so the diameter is 156 billion light years across.

Was a head scratcher when I first read that. The universe is only 13.7b years old. That is when the big bang took place and the universe was formed. So according to Special Relativity, nothing can travel beyond the speed of light, so really the universe should only have a radius of 13.7b light years and a diameter of 27.4b light years.

I guess it's kind of a technicality that the universe is expanding rapidly, so really nothing has violated special relativity, yet the universe is much bigger than anyone would have really conceived using todays physics.

And yes, the farther away you look, the more "back in time" you are looking. Light only travels so fast. Interesting to think that a star we see in pictures may not even exist anymore.

That's right, the universe is thought to, in the very early stages, have gone through a period of huge inflation.. the size increasing faster than the speed of light isn't really an issue though, no more an issue if a shadow crossing a surface travels faster than the speed of light.

http://en.wikipedia.org/wiki/Cosmic_inflation

[photon]

The upgrades to the Hubble are going to be awesome too:

http://space.newscientist.com/articl...ine-news_rss20

[MolsonInBothHands]

Ok, no edges or center to the universe. 3 dimensions expanding into 4? The fourth dimension being time?

Are there images looking towards the perceived epicenter of the big bang?

If I put a performance chip into my truck which allows me to drive 78 billion light years an hour, (Only slightly faster than Deerfoot trail.) and I drove in one direction, where would I be in relation to my starting point after 1, 1.5, and 2 hours? Is there a screen wrap like in the game asteroids?

[photon]

Originally Posted by MolsonInBothHands

Are there images looking towards the perceived epicenter of the big bang?

Look in any direction, you are looking at it.

To use the balloon analogy, when blowing up the balloon, where's the centre of the surface of that balloon? It's a question that doesn't have any meaning, like asking "what colour is sweet"?

If I put a performance chip into my truck which allows me to drive 78 billion light years an hour, (Only slightly faster than Deerfoot trail.) and I drove in one direction, where would I be in relation to my starting point after 1, 1.5, and 2 hours? Is there a screen wrap like in the game asteroids?

I guess in theory, but again because of the limits on the universe it can never happen so it does the question even mean anything.

[MolsonInBothHands]

Originally Posted by photon

Look in any direction, you are looking at it.

To use the balloon analogy, when blowing up the balloon, where's the centre of the surface of that balloon? It's a question that doesn't have any meaning, like asking "what colour is sweet"?



I guess in theory, but again because of the limits on the universe it can never happen so it does the question even mean anything.

I wasn't asking for the center. As in the balloon, there may not be a center on the surface, but there is a source, a cause of the expansion, the nozzle so to speak. Did the big bang not occur from a single point in space/time?

Your last comment confuses me. It was asserted there is no edge (I interpret that as limit) or center to the universe. Yet the limits of the universe make it impossible, are you meaning the limits on our travelling velocity? If so, I was hoping we could put that aside for a second.

I will put it another way. There is no edge, but there is a radius? How can both be true? What I really want to know is if I am able to travel more than the diameter of the universe, does the universe expand as I travel, since I am a part of the universe, or would I have no effect, and simply 'blip to the other side'?

[photon]

Originally Posted by MolsonInBothHands

I wasn't asking for the center. As in the balloon, there may not be a center on the surface, but there is a source, a cause of the expansion, the nozzle so to speak. Did the big bang not occur from a single point in space/time?

In a balloon there's a nozzle, but for the universe the balloon is a perfect sphere, so no not really, it didn't occur from a single point in space/time. Space/time IS the universe.

evman can probably explain it better than me.

Your last comment confuses me. It was asserted there is no edge (I interpret that as limit) or center to the universe. Yet the limits of the universe make it impossible, are you meaning the limits on our travelling velocity? If so, I was hoping we could put that aside for a second.

Yeah I meant the limits on the speed one can travel.. and putting that aside might not be that easy, even in the context of a mental exercise. The speed limit is intrinsic to the structure of the universe so if we leave it out then we are changing the universe we're trying to explore with that mental exercise.. sometimes things can be simplified for use in a mental exercise, but speed feels like something we couldn't.

I'll clarify why I say that in a second.

I will put it another way. There is no edge, but there is a radius? How can both be true? What I really want to know is if I am able to travel more than the diameter of the universe, does the universe expand as I travel, since I am a part of the universe, or would I have no effect, and simply 'blip to the other side'?

When they talk about the radius of the universe, really they usually mean the radius of the "observable" universe. So the 78 billion light year radius thing just means that the light from the beginning of the universe that is reaching us now in combination with the expansion of the universe since the beginning works out to 78 billion light years.

The question about if you were able to travel more than the diameter of the universe, that's a question about the actual geometry of the universe.

If the universe were a sphere (rather a 3-sphere or sphere with higher dimensions, or whatever, I don't know what the right terminology is), then like on the surface of the balloon if you started out in one direction you would eventually end up back where you started (or if you had a big enough telescope you could peer up and see the earth as it was long ago).

Measurements from the cosmic background radiation (radiation from just after the big bang) seem to indicate this isn't the case. So either the universe is infinite (in which case you would just keep going) or has some other shape. Or it could still be a sphere, but the expansion is fast enough that the speed limit prevents us from observing that it is a sphere.

To bring back in the speed limit thing, because the speed of light and the expansion of the universe is intrinsic to the universe, by definition we can't go to the "edge" and then keep going to see what happens, so the question doesn't have a meaning (just like the question of what came before the universe; causality is part of the universe and doesn't have any meaning outside of it).

That last part might be way off though from current knowledge of cosmology, evman150 will hopefully correct me or help explain it better.

[sixpacked]

Originally Posted by photon

In a balloon there's a nozzle, but for the universe the balloon is a perfect sphere, so no not really, it didn't occur from a single point in space/time. Space/time IS the universe.

evman can probably explain it better than me.


Yeah I meant the limits on the speed one can travel.. and putting that aside might not be that easy, even in the context of a mental exercise. The speed limit is intrinsic to the structure of the universe so if we leave it out then we are changing the universe we're trying to explore with that mental exercise.. sometimes things can be simplified for use in a mental exercise, but speed feels like something we couldn't.

I'll clarify why I say that in a second.

When they talk about the radius of the universe, really they usually mean the radius of the "observable" universe. So the 78 billion light year radius thing just means that the light from the beginning of the universe that is reaching us now in combination with the expansion of the universe since the beginning works out to 78 billion light years.

The question about if you were able to travel more than the diameter of the universe, that's a question about the actual geometry of the universe.

If the universe were a sphere (rather a 3-sphere or sphere with higher dimensions, or whatever, I don't know what the right terminology is), then like on the surface of the balloon if you started out in one direction you would eventually end up back where you started (or if you had a big enough telescope you could peer up and see the earth as it was long ago).

Measurements from the cosmic background radiation (radiation from just after the big bang) seem to indicate this isn't the case. So either the universe is infinite (in which case you would just keep going) or has some other shape. Or it could still be a sphere, but the expansion is fast enough that the speed limit prevents us from observing that it is a sphere.

To bring back in the speed limit thing, because the speed of light and the expansion of the universe is intrinsic to the universe, by definition we can't go to the "edge" and then keep going to see what happens, so the question doesn't have a meaning (just like the question of what came before the universe; causality is part of the universe and doesn't have any meaning outside of it).

That last part might be way off though from current knowledge of cosmology, evman150 will hopefully correct me or help explain it better.

Good post, but what is the sound of one hand clapping????

[driveway]

Originally Posted by evman150

You cannot ascribe properties to things unable to have those properties ascribed to them. You cannot make the colour red "smell like vinegar". You cannot give smell to something unable to be ascribed a smell. Etc. Etc. Etc.

Unless, of course, you happen to suffer from synesthesia [ http://en.wikipedia.org/wiki/Synesthesia ] as some people theorise Kandinsky did.



As for big exciting sciencey stuff, I'm seriously pumped about the Large Hadron Collider at CERN coming online this year. Planet-eating black hole here we come!

http://en.wikipedia.org/wiki/Large_Hadron_Collider

[Burninator]

Does anyone know a website where you could order some these super neat space images in a poster or something?

[troutman]

There are a hundred billlll-yun stars in the milky way galaxy, and a hundred billll-yun galaxies. (Carl Sagan)

[CrusaderPi]

I kinda feel like skipping work tomorrow.

[McG]

and to put the space time thing into perspective with the 78 billion light years...if you were 2,000 light years away from earth, you would be able to see Jesus walking on the planet. there would be no way for you to see closer to "real time" without physically being closer.

i read one of the threads on the youtube linky, and the guy was explaining that even when galaxies collide, there is so much space between the stars and planets in each galaxy that there is almost no contact between stars and planets due to collision. in theory, they could pass through each other. realistically speaking though, there will be gravitational effects and things will possibly get drawn together, but without physical proximity to a strong gravity based object, the two galaxies would pass through each other. when you think of a galaxy and all that one contains...that's pretty incredible.

regarding the edge of the universe (and not the star trek episode!), if expansion is occurring at the speed of light then the question about what else is out there starts to become moot. the reason is because not only will we not likely ever know...but even if we were to travel there at light speed it would in theory have doubled...as in the expansion itself. you would literally travel at light speed to the edge of the galaxy "today", and find yourself the same distance from the new edge as we are today. that's crazy!

this btw is an outstanding thread! some really sharp CPers out there!

[worth]

There might almost be no contact between stars, but a direct collisions would leave both galaxies pretty much devastated due to the gravitational forces acting on the galaxies.

http://csep10.phys.utk.edu/astr162/l...colliding.html

[metal_geek]

There are lots of colliding galaxies, and lots of images of them. Most of the time they pass each other several times and finally form 1 Massive galaxy. There are even examples of 3 and 4 galaxies merging!

Here is an excellent picture of a 3 way merger.
http://blog.wired.com/photos/uncateg...birdgalaxy.jpg


And here is one of the better images of a 2 way collision.
http://www.spacetelescope.org/images.../heic0717a.jpg

Here is a gigantic 4 way merger...
http://news.bbc.co.uk/nol/shared/spl...9320/img/1.jpg



As for where to buy pictures like this, there are lots of people that will be happy to sell you a picture. Some of the better "amatures" out there with fantastic stuff are:

Hunter Wilson: http://hwilson.zenfolio.com/f129011888
Garrett Grainger: http://www.beachastronomy.com/main.php
Calgary's own Alan Dyer: No web site for him, but google his name and you'll come up with 1000's of links, books, articles and images of him. I know you can e-mail him, he's very approachable. You can also meet him in person if you really wanted to.
________
Honda bros 400 history