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tponeill
2010-Feb-06, 08:39 PM
Human brains did not evolve with the capacity to easily understand distances in the visible universe. I first began to grasp the size of the universe after pondering the following line of thought:

1. The Voyager spacecraft is outside our solar system, travelling at 11 miles/sec.

2. It will reach the nearest star in the year 73,000 AD.

3. On top of that, there are 200 billion stars in our Galaxy.

4. Then beyond that, there are 200 billion galaxies in the visible universe, with the nearest one, Andromeda, being 2.5 Million light years away.

Which specific lines of thought help you understand the size of the visible universe?

Enlighten us!

EDG
2010-Feb-07, 01:17 AM
"Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."

- Douglas Adams, The Hitch-hiker's Guide to the Galaxy.

:)

J Riff
2010-Feb-08, 07:28 AM
There may have been a big bang near us recently (a few billion years back or was it a trillion ? ) We are looking at less than .1 X 10-infinity of the matter in the universe. This helps me. )
The concept of infinity has been known to shut many fine brains down - the size of the universe is unimportant compared to what these guys are learning about our own galaxy, the stars and planets near us, that's what I would hope to see more of.

" Wait ! What's this switch...? "

Cougar
2010-Feb-08, 02:04 PM
Which specific lines of thought help you understand the size of the visible universe?

This site does a pretty good job of that: The Atlas of the Universe. (http://www.atlasoftheuniverse.com/)

Swift
2010-Feb-08, 02:35 PM
Which specific lines of thought help you understand the size of the visible universe?

Honestly, nothing. I'm not sure I emotionally really grasp it. As you said, I'm not sure the human mind can.

But the Hubble Ultra Deep Field image (http://hubblesite.org/newscenter/archive/releases/2004/07/image/a/format/large_web/) comes close. Most of those little fuzzy patches is an entire galaxy, and this is just a tiny fraction of the sky.

IsaacKuo
2010-Feb-08, 04:28 PM
You could try this:

1) Familiarize yourself with the mathematics of large numbers

2) In comparison, the size of the universe is really small

Good luck with step #1!

EDG
2010-Feb-08, 04:48 PM
Could try the old "Powers of Ten" approach...
http://micro.magnet.fsu.edu/primer/java/scienceopticsu/powersof10/

danscope
2010-Feb-08, 05:05 PM
As big as you think it is........ yep, it's still Bigger! Lots bigger.

Jens
2010-Feb-09, 08:11 AM
Honestly, nothing. I'm not sure I emotionally really grasp it. As you said, I'm not sure the human mind can.


I agree. I don't really think it's possible. The problem with those programs where you look at this, then ten times bigger, then ten times bigger, is that we always end up looking at the big scales reduced to a human scale. I think the human mind can't really grasp it because, honestly, there isn't any reason for us to grasp it. It's kind of like our inability to detect neutrinos. There's just no use for it.

Pie Man
2010-Feb-10, 08:34 PM
And it's not just the size of the universe, I have difficulty imagining....it's the age as well! As Carl Sagan put it:

"The size and age of the Cosmos are beyond ordinary human understanding. Lost somewhere between immensity and eternity is our tiny planetary home. In a cosmic perspective, most human concerns seem insignificant, even petty."

I suppose that ultimately our brains have evolved to comprehend distances on our tiny planetary home, and its associated petty concerns .... the fact that we can make an effort to try to understand the size and age of the universe, in some respects shows the extreme adaptability and flexibility of the human mind and brain. These studies are psychologically light years away from the evolutionary pressures of the savannah of East Africa for which we evolved over thousands of years).... the lion in the long grass or inter-tribal warfare etc. Mind you on a physical level, it's a similar distance in terms of physiology between the Keck 10m telescope and the unaided human retina!

....and once we've tried as hard as we can to come to terms with distance and age, we can then attempt to re-focus on cosmos within - the very small world of sub-atomic particles.....!!!!

Ilya
2010-Feb-16, 08:01 PM
My favorite illustration of cosmic distances:

Imagine Solar System so shrunk that the distance between Sun and Earth is an inch. At that scale Sun is a barely visible spark of light and Earth is microscopic, as are all planets. Jupiter is five inches away, and almost every object ever sent into space by human beings spent its entire existence inside that 10-inch diameter circle, taking months or years getting to its destination. Neptune and Pluto are 2.5 feet away, and Pioneer and Voyager probes, the farthest ambassodors of humanity as of now, are 6-8 feet away -- and took more than 30 years to get there.

On that scale, a light-year is a MILE.

tponeill
2010-Feb-16, 09:39 PM
My favorite illustration of cosmic distances:

Imagine Solar System so shrunk that the distance between Sun and Earth is an inch. At that scale Sun is a barely visible spark of light and Earth is microscopic, as are all planets. Jupiter is five inches away, and almost every object ever sent into space by human beings spent its entire existence inside that 10-inch diameter circle, taking months or years getting to its destination. Neptune and Pluto are 2.5 feet away, and Pioneer and Voyager probes, the farthest ambassodors of humanity as of now, are 6-8 feet away -- and took more than 30 years to get there.

On that scale, a light-year is a MILE.

I really like this one. I wonder how far away alpha centauri would be? About 4 miles, I guess!

Ilya
2010-Feb-17, 06:04 PM
I really like this one. I wonder how far away alpha centauri would be? About 4 miles, I guess!
Well, of course. 4.3 miles, to be more exact.

By a curious coincidence, the number of inches in a mile is VERY close to the number of astronomical units (Earth-Sun distance) in a light-year: 63360 and 63240, respectively. That's what makes this illustration so powerful.

Sadly, there is no equally good illustration in metric units :)

Dgennero
2010-Feb-25, 08:28 PM
Even "small fry" in the universe becomes a huge challenge when it is compared to truly human dimensions.
Try walking to the Moon: The moon is approximately 480,000,000 steps from Earth.
It's about 2,000 steps to the mile.
If you walk 50 miles a day, it still takes 5,000 days or more than 13 years to get there.
Mars at opposition is 36,000,000 miles.
That takes almost 2,000 years.
With a passenger airplane at 600 mph, it takes however "only" about 7 years to Mars if you could go straight "up" there.
The reason this may seem a short time compared to about 6 months for a much faster spaceship is that we cannot go "straight" there.
As for the next star by plane: That would take about 5 million years.
For a fast car, take the plane travel time times five; for rockets, divide the plane figures by 50.
Have a nice trip :)

novaderrik
2010-Mar-02, 09:28 PM
http://www.youtube.com/watch?v=f_J5rBxeTIk

speedfreek
2010-Mar-03, 09:35 PM
But the Hubble Ultra Deep Field image (http://hubblesite.org/newscenter/archive/releases/2004/07/image/a/format/large_web/) comes close. Most of those little fuzzy patches is an entire galaxy, and this is just a tiny fraction of the sky.

Yes, and it is a very tiny fraction of the sky indeed. It would be completely covered by a 1mm square piece of paper, held at arms length.

:)

Bluevision
2010-Mar-03, 10:26 PM
For me, it was probably this (http://en.wikipedia.org/wiki/File:Universe_Reference_Map_(Location)_001.jpeg) Wikipedia image. At that point, it almost makes little difference to remember that there's thousands of those superclusters in the visible universe.

docwatson
2010-Mar-22, 07:36 PM
On top of this discussion of the size of the universe there is also current theory that our universe is merely a tiny bubble in a far larger multiverse. Wrap your mind around that!
http://mikeslightbucket.com

ITTlover
2010-Mar-22, 11:34 PM
I like looking at small to explain big. If an atom was actually the size of a standard marble, my brain would be rougly 25,000 miles across.

Boratssister
2010-Mar-23, 01:14 AM
http://www.youtube.com/watch?v=f_J5rBxeTIk

I like Monty pythons '' meaning of life '' when eric idle climbs out of the fridge in the '' can I have your liver scetch'' .
I would link to it but I'm having a few glitches, if some one else could do the honour feel free.

Life Shape
2010-Mar-25, 11:05 PM
Ever since I was 5 or 6, I had this thought about being dwarfed by a single grain of sand. I Imagine a whole galaxy as a single grain of sand and know that I am just scratching the surface (...well, okay, not even close:))

jonesg
2010-Mar-28, 03:25 AM
The concept of infinity has been known to shut many fine brains down -

Kantor, Boltzman, Godel, all went mad and /or commited suicide playing with infinities. Although there are neat math tricks for dealing with the vastness of space its a safe bet to say its beyond human capacity to actually grasp it.

And when someone does start to exhibit an ability to grasp infinities they seem to lose their capacity to reconcile their phone bill ....over time.

Fiery Phoenix
2010-Apr-08, 08:49 AM
I don't think I do, but then again, I believe I am aware of how large the Universe really is. I think the best way to get a sense of how small and insignificant we are is by co-ordinating a trip out to the country on a clear day and find a good natural spot to wait for the nightfall and breathe the brilliance of the night sky at its amazing best. I know that at any one time on a clear night with no light pollution, about 1500 stars can be seen. Under ideal conditions, as many as 3000 stars can be under a single sky! Now, how incredible and refreshing would that be?

Allow me to say this, guys, but we humans have more or less removed ourselves from the natural world. I think we've reached a point where we're too arrogant to even ponder such things. Hell, I've had moments when people would sometimes make fun of me for being fascinated in space and astronomy. Part of the reason I don't talk about this in front of anyone.

Swift
2010-Apr-14, 03:01 PM
Someone just sent me a link to interactive scale of the universe webpage (http://primaxstudio.com/stuff/scale_of_universe.swf). I thought it was pretty cool.

Note: it does play soft background music, if such things are a concern in your workplace.

ravens_cry
2010-Apr-14, 05:55 PM
I am not sure if this is accurate or not, or even if it will help, but this may interest. (http://www.newgrounds.com/portal/view/525347)

aastrotech
2010-Apr-17, 06:53 AM
Its pretty simple to me. I can see the Milky Way with my naked eye. I can see a human hair with my naked eye. If I scale the Milky Way to the diameter of a human hair the limit of the visible universe is about 9 feet away.

tponeill
2011-Mar-20, 11:55 PM
Its pretty simple to me. I can see the Milky Way with my naked eye. I can see a human hair with my naked eye. If I scale the Milky Way to the diameter of a human hair the limit of the visible universe is about 9 feet away.

I kinda like that! What did you do to get banned?!

astromark
2011-Mar-21, 07:35 AM
I do not except that...and its too small... If you scale the galaxy to be the width of a human hair. The universe is going to be much bigger than eighteen feet across... that might equate to the local group of galaxies.
Use the Light Year Scale. If 0.01 mm = 100,000 L/Y then 14 billion L/Y would = 14 km away.. No that can not be right... It must be 1,400 km, or is it 1,400 millions... where did you get 9 feet ?
I asked first. and I think this is still too small... The pointless question is at the hart of impossible to answer questions.
The Universe by definition is all of everything...It is very VERY big. My head is programed to understand a L/Y and I do.
I can see Sirius and have used a telescope to see Andromeda.. Looking deep into the Hubble Ultra Deep Field... I see those very faint smudges.. and I know they are more of Galactic stuff... and that much beyond 13.7 billion L/Y is never going to be known of... its gone already or never was...and I will never know. BUT I am sure that if I were to scale down this whole MilkyWay Galaxy as to fit inside the width of a human hear... the edge of the Universe is going to be halfway to the moon or further.
Look at the date.... 2010. Hes hardly going to see this...

Spoons
2011-Mar-21, 10:06 AM
I like Monty pythons '' meaning of life '' when eric idle climbs out of the fridge in the '' can I have your liver scetch'' .
I would link to it but I'm having a few glitches, if some one else could do the honour feel free.

I'm a little late, but to complete Boratssister's request... http://www.youtube.com/watch?v=8tmLvzubP3I

Enjoy! (Starts around 3m 50s in.)

novaderrik
2011-Mar-21, 11:43 AM
I kinda like that! What did you do to get banned?!

i'm pretty sure he won't answer..

Spoons
2011-Mar-21, 11:52 AM
Give him time, it's barely been 12 hours. :D