APOD: A Flight through the Hubble Ultra... (2013 Aug 27)

[BDanielMayfield]

I'm glad the flight didn't go very fast. After all the marshmallow and popcorn from yesterday's APOD, i didn't feel like going to fast.
After we got by everything at the end, what's that tiny red dot in the middle of the screen

Actually the flight was very fast. About ten billion ly/minute!

It looks like you and BDanielMayfield have about a 20 Billion light year difference of opinion. The video was less than a minute.

I'm glad the flight didn't go very fast.

Didn't go very fast??? Our virtual starship covered over 30 billion light years in 58 seconds!

Actually the flight was very fast. About ten billion ly/minute!

Dr. Frank Summers from STScI, one of the creator's of the video, commented on facebook:

The speed of the camera through the data set is roughly 200 million light-years per second.

Thank you bystander and thank you Dr. Summers.

So some universal accounting is in order, to reconcile these numbers.

My mistake was to assume that the simulated flight begins here. The simulation doesn’t begin here; it starts at the near edge of the Hubble Ultra Deep Field. Where was that? From the duration x speed we have 58 sec. x 200,000,000 ly/sec. = 11.6 billion light-years.

I came up with 30 billion light-years from this given:

Toward the end of the video the virtual observer flies past the furthest galaxies in the HUDF field, recorded to have a redshift past 8.

So how far out is a redshift past 8? Using the handy dandy Redshift Lookup Table for the Universe that was the APOD for April 8, 2013 I find that the observable radius out to a redshift or “z” of 8 is about 9150 Mpc. Mpc is short for 1 million parsecs, and 1 parsec = 3.26 light-years, therefore 9150 x 1,000,000 pc x 3.26 ly/pc = 29.829 billion lys. So “past 8” would be about 30 billion lys. 30 – 11.6 = 18.4, therefore today’s APOD trip started about 18.4 billion lys out and ends about 30 billion lys out.

Incidentally, a speed of 200 million light-years/sec. is, err, 200 Million times the speed of light of course. (Self edit: WRONG you Dummy! See Mizar's comment below.) That's flat out fast to me, but I haven't been on the ship that long. To an experienced crewmember like Beyond it evidently seems like a leisurely cruising speed.

[geckzilla]

Light is frustratingly slow as far as traveling cosmic distances is concerned but it's still the fastest way to get around. I didn't realize how slow it really is until I sent a light pulse out from the Sun in Universe Sandbox and watched it for a few minutes in real time. Even just waiting for it to reach Earth is a small test of patience. Calling light speed slow has to be one of the most ridiculous things to say but it sure seems slow when you try to watch it in the simulation!

[Mizar]

It says there's no modern spiral galaxies this far back in the universe, but I believe I do see some spiral structure in certain ones. For example, the one on the left edge at 38 sec. into the video.

Whoah, looking at these ultra/extreme deep fields produces an profound feeling of wonder that is hard to describe, and I haven't quite experienced before!!!

• The Red Roof Inn Restaurant at the End of the Universe

Wouldn't that be the Beginning of the Universe?

In temporal terms it would be, but in spatial terms it would be the end/edge (of the visible universe).

Incidentally, a speed of 200 million light-years/sec. is, err, 200 Million times the speed of light of course.

Not unless the video lasted for several decades. Since the speed of light is actually 1 light second/sec., not 1 light year per second, it's actually 6.311 quadrillion times light speed in the video (200 million X ~31,556,736 seconds in a year).

[alter-ego]

Light is frustratingly slow as far as traveling cosmic distances is concerned but it's still the fastest way to get around. I didn't realize how slow it really is until I sent a light pulse out from the Sun in Universe Sandbox and watched it for a few minutes in real time. Even just waiting for it to reach Earth is a small test of patience. Calling light speed slow has to be one of the most ridiculous things to say but it sure seems slow when you try to watch it in the simulation!

To truly appreciate its speed, you must be the photon

[Boomer12k]

Not very scientific observation from me....but....this would make a great SCREENSAVER...

Really nice video...

:---[===] *

[BDanielMayfield]

It says there's no modern spiral galaxies this far back in the universe, but I believe I do see some spiral structure in certain ones. For example, the one on the left edge at 38 sec. into the video.

Whoah, looking at these ultra/extreme deep fields produces an profound feeling of wonder that is hard to describe, and I haven't quite experienced before!!!

• The Red Roof Inn Restaurant at the End of the Universe

Wouldn't that be the Beginning of the Universe?

In temporal terms it would be, but in spatial terms it would be the end/edge (of the visible universe).

Incidentally, a speed of 200 million light-years/sec. is, err, 200 Million times the speed of light of course.

Not unless the video lasted for several decades. Since the speed of light is actually 1 light second/sec., not 1 light year per second, it's actually 6.311 quadrillion times light speed in the video (200 million X ~31,556,736 seconds in a year).

Boy, that was boneheaded of me. Thanks for the correction Mizar, and great comment. 6.311 Quadrillion (6,311,000,000,000,000) times the speed of light leaves a mere 200 million in the dust.

[Anthony Barreiro]

Not very scientific observation from me....but....this would make a great SCREENSAVER...

Really nice video...

:---[===] *

All the expense of building and launching the Hubble Space Telescope, launching several more space shuttle missions to correct the optics and install new instruments, controlling the HST, downloading and processing the data, it was all worthwhile -- Boomer's got a cool screen saver!

[Anthony Barreiro]

Light is frustratingly slow as far as traveling cosmic distances is concerned but it's still the fastest way to get around. I didn't realize how slow it really is until I sent a light pulse out from the Sun in Universe Sandbox and watched it for a few minutes in real time. Even just waiting for it to reach Earth is a small test of patience. Calling light speed slow has to be one of the most ridiculous things to say but it sure seems slow when you try to watch it in the simulation!

On the other hand, the relatively slow speed of light allows cosmic distances to be understood within human terms -- light takes eight minutes to get from the Sun to the Earth, a second and a half to get from the Moon to the Earth, four hours to get from the Sun to Neptune, four years to get from the nearest star to Earth, tens or hundreds of years to get from most of the visible stars to Earth, 100,000 years to get from one edge of the Milky Way to the other, 2.5 million years to get from the Andromeda Galaxy to the Milky Way, 50 million years to get from the big Virgo cluster galaxies to our local group ... . And if spacetime would just stop expanding, light could get from one edge of the observable universe to the other in 42 billion years ... . Okay, 42 billion years is incomprehensible in human terms, but all the earlier steps are comprehensible ... .

[ta152h0]

This is similar to diving in a lake near shore and watching all the beings and things float by you as you " paddle away " One difference is there is a dock waiting for you, maybe !

[Mactavish]

Sheeeesh!

[geckzilla]

On the other hand, the relatively slow speed of light allows cosmic distances to be understood within human terms -- light takes eight minutes to get from the Sun to the Earth, a second and a half to get from the Moon to the Earth, four hours to get from the Sun to Neptune, four years to get from the nearest star to Earth, tens or hundreds of years to get from most of the visible stars to Earth, 100,000 years to get from one edge of the Milky Way to the other, 2.5 million years to get from the Andromeda Galaxy to the Milky Way, 50 million years to get from the big Virgo cluster galaxies to our local group ... . And if spacetime would just stop expanding, light could get from one edge of the observable universe to the other in 42 billion years ... . Okay, 42 billion years is incomprehensible in human terms, but all the earlier steps are comprehensible ... .

Comprehensible to some, at least. I think it's kind of like visiting the Pyramids of Egypt. Until you are standing right next to one, its mass just isn't tangible. They exist in one's mind as a series of adjectives and it is known that they are enormous but to see even a very good photo is much different from standing near one. It's easy to see our solar system as an illustration in a book and have everything feel comfortably close together and a visit to one object or another something like a trip across an ocean. An ocean simply doesn't suffice as a metaphor for space. The word "lightyear" is used so much and most people understand it by definition but for it to really sink in I think it takes more than a verbal description.

[neufer]

This is similar to diving in a lake near shore and watching all the beings and things float by you as you "paddle away "

One difference is there is a dock waiting for you, maybe !

Maybe

[Beyond]

[Ann]

Anthony Barreiro wrote:
Okay, 42 billion years is incomprehensible in human terms, but all the earlier steps are comprehensible ... .

Anthony, you mean 42 billion years as in 42 billing light-years, don't you?

I once built a super-simple model of the inner solar system. I used cotton balls, 0.02 meters in diameter, for the Earth, Venus and Mars. I used yellow peas for Mercury and the Moon, and a round table-cloth, 2 meters in diameter, for the Sun. I then placed the "planets" at the appropriate distances from the Sun. The Earth was about 200 meters from the Sun.

I couldn't believe how tiny cotton ball Earth looked when it was placed 200 meters from table-cloth Sun! And I couldn't believe how vast the depth of those 200 meters looked in comparison.

I had "scaled down" the size of the inner solar system some 700,000,000 times. I was able to picture in my mind, more or less anyway, how big the Earth actually is. But when I tried to picture the actual, physical depth of those 200 X 700,000,000 meters in my mind, trying to sum it up by adding kilometer after kilometer until I got to 140,000,000,000 kilometers - okay, it should have been 150,000,000,000 kilometers instead, big deal - I found that I couldn't do it.

I'm sure that there are people out there who are much better at imagining the stark reality of 8 light-minutes in their minds. I'm sure there are those who can do it.

But if people tell me they can actually imagine a light-day, 24 light-hours, I'm not sure I believe them any more.

And imagining - actually imagining the physical reality of a light-year, I'm quite convinced it is humanly impossible.

So, Anthony, if you can actually comprehend all the steps leading up to 42 billion light-years, then you are 42 billion light-years and 8 light-minutes ahead of me.

Me, I can juggle the figures a bit. I can easily understand the difference between 21 billion light-years and 42 billion light-years, for example. Sure I can do that sort of thing.

But to comprehend the actual reality behind those figures... I can find no word to explain how impossible that is to me. Impossible, impossibler, impossiblest, mega super duper gobsmackedly impossiblest. And then some.

And you know what? I like it. The universe doesn't have to stop expanding as far as I'm concerned!

Ann

[DavidLeodis]

The Hubble Ultra Deep Field view is fascinating. Mind-boggling, but fascinating!

A couple of things in the HUDF release (STScI-2004-07, released on March 9 2004) help give some sense of scale:-

7. If astronomers made the Hubble Ultra Deep Field observation over the entire sky, how long would it take?

The whole sky contains 12.7 million times more area than the Ultra Deep Field. To observe the entire sky would take almost 1 million years of uninterrupted observing.

8. How wide is the Ultra Deep Field's slice of the heavens?

The Hubble Ultra Deep Field is called a "pencil beam" survey because the observations encompass a narrow, yet "deep" piece of sky. Astronomers compare the Ultra Deep Field view to looking through an eight-foot-long soda straw.

The Ultra Deep Field's patch of sky is so tiny it would fit inside the largest impact basin that makes up the face on the Moon. Astronomers would need about 50 Ultra Deep Fields to cover the entire Moon.

[DavidLeodis]

I'm confused by the image used as the APOD as I do not seem to be able to spot where that view is in the video, though as it is full of objects it would seem to be near the start. I wonder if it is a very greatly enlarged part of the video? The various colours in that image are intriguing.

Edit added around 15:20 on August 28 2013. On looking at the video again a few times it now seems to me that the APOD is an enlargement of a scene at about 28/29 seconds in the video.

[Psnarf]

Sulu, reverse engines....Slowly!

[DOUGLAS L. MARTIN]

HOW CAN SOMETHING TRAVEL THROUGH 30 BILLION YEARS IN A UNIVERSE ONLY 13.7 BILLION YEARS OLD?

[neufer]

HOW CAN SOMETHING TRAVEL THROUGH 30 BILLION YEARS IN A UNIVERSE ONLY 13.7 BILLION YEARS OLD?

The same way that photons from the Big Bang did it

[BDanielMayfield]

So many insightful comments, lightly seasoned with humor. What a great thread this is!

Anthony, I’m right with you in your thinking that we sort of have a mental handle on astronomical distances, but then Geckzilla and Ann had to go and pull the rug out from under us didn’t they. There’s nothing quite like actually building a scale model to put things in proper perspective, and Ann was just modeling the solar system, the distances of which pale into insignificance when compared even just with the next rung up the ladder; interstellar distance.

The Hubble Ultra Deep Field view is fascinating. Mind-boggling, but fascinating!

A couple of things in the HUDF release (STScI-2004-07, released on March 9 2004) help give some sense of scale:-

7. If astronomers made the Hubble Ultra Deep Field observation over the entire sky, how long would it take?

The whole sky contains 12.7 million times more area than the Ultra Deep Field. To observe the entire sky would take almost 1 million years of uninterrupted observing.

8. How wide is the Ultra Deep Field's slice of the heavens?

The Hubble Ultra Deep Field is called a "pencil beam" survey because the observations encompass a narrow, yet "deep" piece of sky. Astronomers compare the Ultra Deep Field view to looking through an eight-foot-long soda straw.

The Ultra Deep Field's patch of sky is so tiny it would fit inside the largest impact basin that makes up the face on the Moon. Astronomers would need about 50 Ultra Deep Fields to cover the entire Moon.

Great comment David. So the image this simulation was made from covered only 1/12,700,000th of the sky. There was absolutely nothing special about this location in space. This site was simply just an extremely empty looking patch of sky, with no foreground stars or galaxies in the way. In even large land based telescopes this must look like an untold number of other boring looking dark, empty places with maybe only a few, barely discernable faint fuzzies, if anything at all. But keep Hubble focused on this place for nearly a million seconds and voila, 10,000 galaxies appear! (To make the video Dr. Summer’s team estimated the distances of about 5,000 of these.)

So this random sampling probes a volume of space of between about 18.4 and 30 billion light-years out and found about 10,000 galaxies. Across the entire celestial sphere this would indicate the presence of 10,000 x 12.7 million = 127 billion galaxies, not counting any less than 18.4 B ly nor any more than 30 B ly away. If the density of galaxies inside the 18.4 billion light-year radius is about the same as that inside the volume probed by the HUDF survey we would have another 38 billion galaxies, so this survey suggests the presence of at least around 165 billion galaxies in the observable universe.

I suspect that 165 billion could still be a major undercount, due to the fact that the further out we look the brighter the galaxy must be to be seen at all, and so many dim and or small galaxies could be overlooked, even by Hubble. Therefore the density of galaxies could be underestimated. Galactic formation and destruction via mergers complicate the accounting, of course.

[BDanielMayfield]

HOW CAN SOMETHING TRAVEL THROUGH 30 BILLION YEARS IN A UNIVERSE ONLY 13.7 BILLION YEARS OLD?

I’m going to boldly go where I haven’t dared to go before and attempt to answer your question Douglas, since it is such a commonly occurring, logical one. Hopefully my crude, simple answer will be corrected if needed and elaborated on by others more informed than I.

We can see objects that are NOW further than 13.7 billion light-years, but no light has been traveling longer of course. But as light travels through space, space itself is expanding, carrying source and observer apart. The estimated distance of 30 billion light-years is the co-moving distance, accounting for the separation that has occurred during the time the light has taken to get to us.

If my explanation is wrong or can be improved upon I welcome comment.

[geckzilla]

HOW CAN SOMETHING TRAVEL THROUGH 30 BILLION YEARS IN A UNIVERSE ONLY 13.7 BILLION YEARS OLD?

I’m going to boldly go where I haven’t dared to go before and attempt to answer your question Douglas, since it is such a commonly occurring, logical one. Hopefully my crude, simple answer will be corrected if needed and elaborated on by others more informed than I.

We can see objects that are NOW further than 13.7 billion light-years, but no light has been traveling longer of course. But as light travels through space, space itself is expanding, carrying source and observer apart. The estimated distance of 30 billion light-years is the co-moving distance, accounting for the separation that has occurred during the time the light has taken to get to us.

If my explanation is wrong or can be improved upon I welcome comment.

If a guy throws a baseball at you while he is 13.7 meters away from you and then you both immediately run away from the ball after it's released, by the time the ball hits you in the back of the head the guy and yourself are already 30 meters apart from one another. The distance between yourself and the guy at the moment the ball was released and the distance between the both of you the moment it hit you in the head are two different measurements.

That's my metaphor-for-dummies explanation for this one. Made by a dummy for dummies.

[BDanielMayfield]

It works for this dummy. However, I must admit slight aversion due to the metaphor’s implication of rampant cowardice.

[Anthony Barreiro]

On the other hand, the relatively slow speed of light allows cosmic distances to be understood within human terms -- light takes eight minutes to get from the Sun to the Earth, a second and a half to get from the Moon to the Earth, four hours to get from the Sun to Neptune, four years to get from the nearest star to Earth, tens or hundreds of years to get from most of the visible stars to Earth, 100,000 years to get from one edge of the Milky Way to the other, 2.5 million years to get from the Andromeda Galaxy to the Milky Way, 50 million years to get from the big Virgo cluster galaxies to our local group ... . And if spacetime would just stop expanding, light could get from one edge of the observable universe to the other in 42 billion years ... . Okay, 42 billion years is incomprehensible in human terms, but all the earlier steps are comprehensible ... .

Comprehensible to some, at least. I think it's kind of like visiting the Pyramids of Egypt. Until you are standing right next to one, its mass just isn't tangible. They exist in one's mind as a series of adjectives and it is known that they are enormous but to see even a very good photo is much different from standing near one. It's easy to see our solar system as an illustration in a book and have everything feel comfortably close together and a visit to one object or another something like a trip across an ocean. An ocean simply doesn't suffice as a metaphor for space. The word "lightyear" is used so much and most people understand it by definition but for it to really sink in I think it takes more than a verbal description.

I find it more helpful to stand outside under a dark night sky with somebody who knows what they're talking about than to look at illustrations in a book or on a computer screen. Or rather, observing the actual sky is a necessary complement to book learning, perhaps like visiting the pyramids makes your preparatory study come alive.

Anthony Barreiro wrote:
Okay, 42 billion years is incomprehensible in human terms, but all the earlier steps are comprehensible ... .

Anthony, you mean 42 billion years as in 42 billing light-years, don't you?

Isn't the observable universe estimated to be 42 billion light years across? So if the universe suddenly stopped expanding, light would take 42 billion years to travel across the universe, right?

I once built a super-simple model of the inner solar system. I used cotton balls, 0.02 meters in diameter, for the Earth, Venus and Mars. I used yellow peas for Mercury and the Moon, and a round table-cloth, 2 meters in diameter, for the Sun. I then placed the "planets" at the appropriate distances from the Sun. The Earth was about 200 meters from the Sun.

I couldn't believe how tiny cotton ball Earth looked when it was placed 200 meters from table-cloth Sun! And I couldn't believe how vast the depth of those 200 meters looked in comparison.

I had "scaled down" the size of the inner solar system some 700,000,000 times. I was able to picture in my mind, more or less anyway, how big the Earth actually is. But when I tried to picture the actual, physical depth of those 200 X 700,000,000 meters in my mind, trying to sum it up by adding kilometer after kilometer until I got to 140,000,000,000 kilometers - okay, it should have been 150,000,000,000 kilometers instead, big deal - I found that I couldn't do it.

I'm sure that there are people out there who are much better at imagining the stark reality of 8 light-minutes in their minds. I'm sure there are those who can do it.

But if people tell me they can actually imagine a light-day, 24 light-hours, I'm not sure I believe them any more.

And imagining - actually imagining the physical reality of a light-year, I'm quite convinced it is humanly impossible.

So, Anthony, if you can actually comprehend all the steps leading up to 42 billion light-years, then you are 42 billion light-years and 8 light-minutes ahead of me.

Me, I can juggle the figures a bit. I can easily understand the difference between 21 billion light-years and 42 billion light-years, for example. Sure I can do that sort of thing.

But to comprehend the actual reality behind those figures... I can find no word to explain how impossible that is to me. Impossible, impossibler, impossiblest, mega super duper gobsmackedly impossiblest. And then some.

And you know what? I like it. The universe doesn't have to stop expanding as far as I'm concerned!

Ann

Scale models are pretty cool. Guy Ottewell's 1000 yard model of the solar system (or, the Earth as a peppercorn) is a lot of fun to experience. I once had the opportunity to walk along such a model on Ocean Beach here in San Francisco. At this scale, Alpha Centauri would be a 20 cm wide beach ball in Lima Peru. That is a vast scale, but comprehensible.

[Zesago]

Where's Carl Sagan and his dandelion spaceship from Cosmos when you need him with a little Vangelis music in the background?

I heard the Cosmos music in my head when I was watching this. Cheers!