This [0] IMHO gives more perspective (don't be taken aback by the flashy images, the good stuff comes after, ~2:50 mark) When watching, remember this is when looking at the absolute darkest spot of our sky.
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 Hitchhiker's Guide to the Galaxy
I still remember the time I saw the first Hubble Deep Field. The idea that the researchers could point this massive telescope at an empty part of the starfield, run a long exposure, and come back with a plate full of galaxies full of solar systems full of planets, while we've yet to get too far beyond the surface of our own.
A lot of people's first reaction always seems to be "we're so insignificant!" And yet, most fascinating to me is trying to reconcile the vast complexities of our planet and of humans with our physical near-nonexistence in the universe.
We have infinite complexity in approximately zero space. Kind of a strange thing to consider.
"A lot of people's first reaction always seems to be "we're so insignificant!" "
Neil deGrasse Tyson often counters this reaction by pointing out that while the universe is vast, we are made of it. So we are not simply small separate objects in a large universe, we are actually part of the physical elements that make it up and come from the same "stuff". At least that's what I gather when he says this:
"Recognize that the very molecules that make up your body, the atoms that construct the molecules, are traceable to the crucibles that were once the centers of high mass stars that exploded their chemically rich guts into the galaxy, enriching pristine gas clouds with the chemistry of life. So that we are all connected to each other biologically, to the earth chemically and to the rest of the universe atomically. That’s kinda cool! That makes me smile and I actually feel quite large at the end of that. It’s not that we are better than the universe, we are part of the universe. We are in the universe and the universe is in us.”
Feynman countered this by saying we're extremely large compared to atoms and fundamental particles, so we can "sit in the middle and enjoy everything both ways."
I remember reading a quote once and you will have to forgive me for not remembering who said it but the approximation of it was "all will be known when the scientist looking trough the telescope, see the scientist looking back at him, through the microscope on the other end". I though it was a great quote about the recursiveness about the big questions. That amazing part about it is the relevance of it, we really don't know how big or small we are it is all perspective, for all we know the universe is a singularity in another perspective. If you traveled far enough fast enough and looked back on the universe it would be a singularity, as time and distance are related so you would be looking at the universe pre-big bang or from the perspective of distance however you want to view it.
I like to think of humans as being part of the evolution of the universe. The universe has evolved to the point where it is now able to ponder its own existence.
>>A lot of people's first reaction always seems to be "we're so insignificant!"<<
I feel the emotion of this reaction, but I think the proper response to this is the one that C.S. Lewis gave: size is just a number; significance is attached to things by minds.
If you don't think tall people more important than short ones, or feet more important than eyes, why do you think stars more important than people? Certainly the stars don't think any such thing. They don't think at all. We do.
Here's a quote from his space novel "Perelandra" where this concept comes up:
"Part of him still knew that the size of a thing is its least important characteristic, that the material universe derived from the comparing and mythopoic power within him that very majesty before which he was now asked to abase himself, and that mere numbers could not over-awe us unless we lent them, from our own resources, that awfulness which they thmselves could no more supply than a banker's ledger. But this knowledge remained an abstraction. Mere bigness and loneliness overbore him."
Kilgore Trout is a fictional character. You could ask Kurt Vonnegut, who invented him, but he's dead. You can certainly assume that it's meant to be humorous.
For one, it's a clever, humorous phrase, since the conventional wisdom is that the universe IS the biggest place, so there would be no reason for "perhaps".
Second, it also entertains some doubt: perhaps the universe IS NOT the biggest place. Maybe the conventional wisdom is wrong. Maybe other places exists, from the mythical and spiritual domain (like paradise and hell and Valhala etc), to the scientific domain (multiverses, many worlds interpretation of QM, etc).
Interesting thought. I wonder, though, what makes those places separate from the universe? The universe including those other places, metaphysical and scientific, would be even bigger and more mind-boggling.
Well, you have to define the universe at some point, and the most common definition on people's minds it's "this thing which our galaxy is in". I would presume that common perceptions don't include such notions as "separate reality split-universes" and sets of multi-verses, and what have you.
If anyone can come up with any larger numbers I'd like to hear them.
EDIT: Oh and if you think the universe is big and hard to imagine, try considering the phase space of the entire universe! That's the set of all possible configurations of all the particles. Bananas.
I encourage you to watch this lecture from Roger Penrose, Aeons Before the Big Bang,
...if only for the fantastic hand-drawn overhead transparencies in all the colours of the rainbow. They are a delight and I want to see hipster programmers using them at conferences.
Yes, I know Shannon's number is "small". The point was that it's been around for a while, and that with the right mathematical tools one can deal with such numbers without having their mind boggled.
Fair enough. I clicked on the link expecting to get something like graham's number or TREE(3) or some other monstrosity, and felt kind of cheated when it was only 10^43 ;)
Do those mathematical methods really allow us to comprehend these numbers though? They only really allow use to express them as configurations of other numbers don't they? Even if you understand hyperoperations and stuff you're not really gazing upon what those figures really entail.
I suppose all mathematics involves notation in the end.
Sure, but there is still something to be said for bound finite numbers. The universe is somewhere between 26 billion light years wide and infinity. From what we can observe it might be reasonable to guess that it's smaller than grahm's number of light years wide, but for all our hubris that's still just a reasonable guess.
Author estimates over 200k galaxies in the image. Image covers 0.004% of the sky.
200000/0.00004 = 5,000,000,000 galaxies. (edited, thanks to % help from commenters below)
Finding somewhat standardized values for this rather standard question is frustratingly vague. Estimates range from a few billion to a trillion, though the most frequently quoted number I could find was about 100 billion.
The standard for measurement in the last 10 years or so have been the Hubble Deep Field Survey images. In the last one done, there were about 10k galaxies shown. The HDFS had a square arcminute resolution of 11.5. It would require 12,913,983 HDFS-type images to cover the entire side. (ref: http://curious.astro.cornell.edu/question.php?number=720)
Using these numbers:
12913983 * 10000 = 129,139,830,000 galaxies.
So why the vast difference between the two numbers? My supposition is the new ESO image isn't as deep as the HDFS.
I would argue the larger number, ~129.134 billion galaxies is a bit more accurate.
Damn, 129 billion galaxies. Someone else has to be out there.
Most probably. THe universe is Big. But it also is Old.
Most probably someone else was or will be out there. Homo Sapiens Sapiens has a currently very short history (~200k years ?). History is 6000 years old (China?). The universe is 13 billion years Old.
Galaxies are not evenly distributed. But for all I know this is an unusually sparsely populated part of the sky. Still, your number could shift in either direction by quite a lot.
That is an excellent point. To further refine the estimate we need measurements of the number of galactic clusters and their various densities. For example, in the Local Group (Milky Way, Andromeda, etc) there are about 50. The Virgo Supercluster contains over 2500. Getting those estimates is beyond me at the moment.
Galaxies are strung out across the universe along filaments, with vast voids in between. The voids are mostly empty and very cold, but recent observations have found hot spots in some up to millions of degrees. Overall, the universe has a soapy appearance, i.e. lots of space with the "stuff" strung together.
One thing to note is that, at least to my knowledge, there are galaxies in all directions. There may be voids along the way, but you'll always see them closer or further away.
One of the reasons that this ESO deep field view is important is that its bigger than the original Hubble Deep Field, so we can start answering questions about density and distribution.
The author's calculation seems to be off, 1.2 x 1.5 degrees is 1/72,000 of the total sky area, or roughly 0.0014% (not 0.004%). That still leaves an order of magnitude to be accounted for, but considering the ballpark nature of the 200k estimate and also this being a "dark" spot it's not very surprising.
When chucking those numbers through the drake equation it looks pretty likely. I think it comes down to a matter of time, both for searching and because I believe we have entered a very dangerous period for a species where technology can either be our savior or cause us to destroy ourselves.
and if the multiverse ends up being true that number might be slightly larger, and by slightly I mean unimaginably larger, I think it's called infinity.
I still remember when I learned that the Sun was a star. I was six years old when my uncle told me about it. I actually asked him what the Sun was and his answer pretty much shocked me to the core. I already knew the Earth revolved around the Sun so learning that the Sun is just one of little tiny bright lights at night was a true eye opener. That night I looked up the sky again and wondered if there are other people up there.....
Oops misstype! We still have 5 billion years before we could refer to it as "was a star".....lol
I just type what comes to mind and rarely do editing.....
Actually, in narrative writing, as you were doing, you should use consistent tense. So you were correct to use "was," as the sun was a star back then, independent of the fact that it also is now.
That's probably why it just came naturally to me because I do read quite a bit and may have seen this word arrangement many times before. My subconscious mind were just spitting out words as I write them. English is only my second language though, I am so much better in Filipino.....lol
Totally unrelated to the universe (but maybe not): To me the "Ye. Gads" moment came after this quote:
"There’s a long jet of material apparently coming from that bloated galaxy on the left (I increased the brightness and contrast of this picture to make it more obvious; it was subtle in the original image but I have a lot of practice picking out things like this)."
I am once again totally stupified at the level of image processing a trained brain paired with a good visual system can do. One day, instead of developing complicated image processing algorithms, we will have it done by a brain-in-a-vat & computer implant combo, using different animal brains and visual systems for different applications, e.g. an owl or eagle for detecting pinpoints of light in a large image of the universe.
I'm surprised someone hasn't converted the large image over to something like the Google Maps navigation UI for better viewing. I guess I'll be attempting that when I get home from work.
> How could there not be a few Death Stars inhabited by English-speaking humans somewhere in one of those galaxies?
I know this is just a tongue in cheek comment, but I actually thought it somewhat reasonable until recently when I spent a moment with the numbers and saw its impossibility.
Basically, there's only ~100 billion galaxies with ~100 billion stars each (to an approximation of several orders of magnitude...), while the space of possible societies, languages, histories, etc, grows exponentially.
Even if there were 10^100 stars, log_2(10^100) is still only about 330. This means all those stars can only accomodate 330 forks in history where it could have gone one way or the other with equal probability. Or, in computer science terminology, all those stars can only encode 330 bits of information. And describing English alone takes far, far more than 330 bits. (Depending on how inevitable language of a certain type is.)
> This means all those stars can only accomodate 330 forks in history where it could have gone one way or the other with equal probability. Or, in computer science terminology, all those stars can only encode 330 bits of information. And describing English alone takes far, far more than 330 bits.
There's a huge gap in your logic here. The number of bits to represent all the stars in the universe has nothing to do with the possibility that there is some English speaking society out there.
Note that your numbers apply to the observable universe. The universe as a whole is likely to be infinite. Not that there is much practical difference between "the universe" and "the observable universe".
What I find interesting about this question is that it is at once fascinating and silly. Fascinating because it would be incredibly cool to have someone like us somewhere out there. Silly because the distances involved are mind boggling, so it is highly unlikely they would ever be able to contact us.
So is there any real difference between they not existing at all and they existing and we (probably) never been able to know that they exist? All we can hope is to hopelessly theorize and write science fiction stories about them.
Interestingly we don't actually know how big our Universe is, perhaps even within a great many orders of magnitude. This is because the visible Universe has expanded at sub-light speeds over its history, but in the very, very early Universe there was a period called inflation in which space-time expanded at speeds much faster than light.
How can you NOT want to travel the universe when you see such a wonderful photo ? Imagine going closer and closer to a perfectly spiral shaped galaxy, effectively discovering a new world, all-so-different yet similar to ours... I get goosebumps just thinking about this..
I know I'm very probably not gonna get to leave Earth in my lifetime, but I genuinely hope that my children or grandchildren will. This opens so many possibilities...
With all this out there it leaves one to wonder, when will the aliens finally get here?
But really, if we evolved from chaos and minerals (so far that's the best explanation anyone's given me.) Then somewhere on some of these other planets are sentient creatures looking up going, "I wonder if there are other sentient creatures out there?"
That is pretty impressive. I wish there was something like this that showed travel between two points, say earth and Alpha Centauri, but at lightspeed or faster with a timer in years at the bottom like an odometer. I imagine that would impart a greater sense of scale for myself.
I don't understand one thing: how can they keep the telescope stable and focused so accurately on one spot in the sky, without any jitter? The Earth is rotating at 360 degrees/24 hours, which is about 0.25 degrees per minute. This 17000 pixel image covers 1.2 degrees, which means the light is sweeping across this sensor at 60 pixels/second as the earth spins.
How can they move the telescope so accurately that a sensor pixel picks up light from the exact same spot in the sky for an extended duration of time?
So you're saying that we have the ability to make sure that a pixel on the sensor is collecting light from the exact same spot in the sky for an extended amount of time? Taking into account (among other things) the rotation of the earth, the shaking of the ground, the wind, the changes in the atmosphere's temperature and humidity and god knows what else?
To put this image in further perspective, take a look at this link[1]. It blew my mind as I had the universe and observable universe all mixed up conceptually. For instance, the universe was not a point at the big bang: only the observable universe was.
Unfortunately I have the same attitude. With the expansion of the universe apparently speeding up, it's like a race we can't win. Unless wormholes DO exist...that would be great. Or maybe we'll discover some mass relay type thing ;) If you haven't played Mass Effect, I'm sorry.
Dude, it's not about the attitude, it's about the numbers. The closest galaxy is four million light years away. Unless there is a major scientific breakthrough in the eons to come that will allow us to travel at speeds 100 times the speed of light there is practical no way to make such a trip. Even with a speed like that and taking under consideration the special relativity which says that time for those traveling will be passing a lot slower than for the rest of use, you'd need at least a millennium to do such a trip.
So you don't try to short cut the laws of physics you fix the weakest links, the biggest one being the longevity of humans. It is realistic to think that given enough time we will be able to replicate organic machines with electro-mechanical ones. Someone somewhere is going to volunteer to upload themselves into one of these machines and we blast them off into space. In the end we always seems to achieve the dreams of the human spirit, 9 times out of 10 they are never the way we envisioned we would. Take flight, early man envisioned wings like a bird and not machines like a plane, but in the end we achieved flight something many people said would never happen, that I am sure of. I think we will achieve intergalactic travel, but it will be nothing like what we envision it to be today, something will come out of left field that will enable it. The challenges are daunting but so was flight at one point in human history.
Exactly! in the future, One can build robots or artificially intelligent machines that can travel and make some decisions on themselves. Such machines will not need most biological conditions needed for organic life to survive. So can live in many hostile conditions.
They can also clone themselves mining the resources and energy available at anywhere they land.
I think the actual feasibility of man made annihilation is smaller than what it is made out to be by the media and entertainment industry. The two most popular ways that are highlighted are nuclear war or bio-engineered pathogen. As far as the first one goes, nuclear war will only eliminate the population centers and irradiate everything, there would be survivors and they would adapt to the conditions.
The second, a pathogen, is just as unlikely to get every last one of us. A virus with a 100% kill rate is highly unlikely. Look at Ebola, while weaponized Ebola would get a great deal of us it's kill rate is somewhere in the 90%'tile, I don't know the exact number but I know it is high and I believe that it is the highest. 10% of the earth population is still allot of people. Even if it is less than that, somewhere their will be a group of people that for whatever reason are resistant to the pathogen.
The only thing that I think is a real threat to our existence today, is a big piece of something floating around out there, deciding to slam into us down here. I don't think we have the capability to do it to ourselves. I heard someone say that it is likely that we will keep resetting ourselves back to the stone-age at a certain mark in technological progress, which I think is a little more feasible, but I personally believe that mans desire to cull different people is self regulation for whatever reason.
Hate to continue the chain, but on the off-chance government organisations know more than they're letting on, we might need to extend that to "most humans". Though, in that case, it might have to be "thought by most humans"? Just speculating for the hell of it. e.g.,
Fixed: Earth is known by most humans as the only planet to have life.
[0] Hubble Ultra Deep Field in 3D http://www.youtube.com/watch?v=oAVjF_7ensg
PS: Inevitably, the title reminded me of this: