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The extent of the known Universe [video] (haydenplanetarium.org)
63 points by neya on March 4, 2012 | hide | past | favorite | 25 comments



Whenever I hear someone talking about the scale of the universe I just can't help but bang on about the Hubble ultra deep field picture: http://hubblesite.org/newscenter/archive/releases/2004/07

If you can look at this picture and "get it", it will blow your mind. It's no wonder people call it the most important picture humanity has ever taken.


I usually think of the Pale Blue Dot photograph. http://en.wikipedia.org/wiki/Pale_Blue_Dot


Not a plug for Nikon, but they do put out a pretty awesome interactive "scale of the universe" thing. The attention to detail is noticably more than the htwins one. You can find it here: http://www.nikon.com/about/feelnikon/universcale/index.htm


The scale of the universe: http://htwins.net/scale2/


The estimated size of the universe beyond the visible part is at most a guess. It could be infinite. This would mean that even at the time of the big bang there was a lot of volume, just very high energy density.

What we do know is that the part universe we live in has an event horizon. We can see distant objects as they looked in the past. The distance to those objects may be as much as 40-50bn light years now, due to the expansion of space.

And if we ventured to travel, even at the speed of light, there are sections of the universe visible now that will fall out of view, and we therefore never reach. If the universe is accelerating, the region of possible travel will shrink.

So we have a so-called "visible universe", a region we can observe or directly infer the effects of. Then there is the "accessible universe", the region we could travel in at the speed of light. All this embedded in a presumably larger, but inaccessible universe.


wow this was amazing!! thanks for sharing!! everyone with kids aboard should watch it!!



It's amazing to see exactly what we've been able to achieve. I never though we knew THAT much about our Universe. I would shake the hand of everyone who helped make it happen if I could.

Also, I don't understand how you can look at how many planets there are and still say that it is impossible for there to be any intelligent life in the Universe.


“Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us.”

- Calvin & Hobbes


Now imagine the theory of ultra-massive black holes creating white-holes on the other side, essentially our "big bang", and that each one is creating another universe just like this one.

Repeating probably like a fractal where we are just a point the tree. Staggering.


Thank you so much for sharing this!

I sent it to some friends that keep saying "we are the only one in universe" and they keep quiet now, lol!

Look at this and think about one small planet (Earth) and only on it you have six billion human-beings and every each of them has its own world...

Watching how many billions of light years we need to "get out" is pretty sad at some point. I hope Gates would say "we will never need to travel with the speed of a light" :) </joke>


Yes, I agree with you, I share the same view too. Just imagine the possibilities..Even if you did a simple probability math, the answer would be obvious - You're not alone.


I'm not sure how probability math would help you, since we have no way of estimating the probability of intelligent life spontaneously occurring outside of our sample size of 1.

What if the probability was 1x10^-80 ?


Hah..I was thinking of something even simpler - Lets assume for simplicity, there is only one habitable planet in the entire Milkyway galaxy, Earth. And there are 'y' number of planets in Milkyway in total. Then, the probability of finding a habitable planet (Earth) in such a galaxy is 1/y. We know that the Milkyway isn't the only galaxy. Let there be totally 'z' no. of galaxies in this universe. Let the percentage of them being a galaxy like Milkyway (where there is a probability of finding a habitable planet) be 'x'. So there exists'x' percent of 'Z' number of Galaxies that may have 1 habitable planet each. Mathematically, thats (x/100)z. Honestly, analyzing (1/y) for each galaxy in (x/100)z should lead you to believe that there exist intelligent life forms apart from just earth. That's such a large number to ignore and it would not be appropriate to say that there exists only one planet, Earth with intelligent life form. I'm not saying this is correct, I'm just justifying what my logic tells me - There's a large chance that there are intelligent life forms elsewhere in the Universe. Why? Because, we are a living example part of the same Universe, so there's no reason why there couldn't be others like us.


Your probability calculations are invalid.

> Lets assume for simplicity, there is only one habitable planet in the entire Milkyway galaxy, Earth. And there are 'y' number of planets in Milkyway in total.

Okay...

> Then, the probability of finding a habitable planet (Earth) in such a galaxy is 1/y.

This does not follow. I'm going to quote Feynmann here:

"You know, the most amazing thing happened to me tonight. I was coming here, on the way to the lecture, and I came in through the parking lot. And you won’t believe what happened. I saw a car with the license plate ARW 357. Can you imagine? Of all the millions of license plates in the state, what was the chance that I would see that particular one tonight? Amazing!"


+1. Good read, thanks. I actually wonder if we would ever make that contact (whether we or they) I wonder if they would be more advanced or less. Lets assume more - then it would be interesting to see if it took them more time to come up with solutions to certain problems we facing, and R&D of hard stuff like anti-gravity, etc. And then, even more interesting, how fast would our world change and what kind of implication on an average Joe would it had, if they would agree on sharing all those "secrets". It would be like putting entire human kind on fast forward into year 2,500. Imagine someone handing you a recipe book: Chapter 1. how to travel faster than light; Chapter 2. how to teleport goods and living organisms; 3. how to grow safe food loaded five times more with nutritions; Chapter 4. how to generate electricity without harming environment; Chapter 5. how to extend human life up to 250 years. Chapter 6. how to peacefully transform world into more friendly place :)


I'm not sure if this would interest you, but there are some theories suggest that you can "use" your mind to travel through the universe, faster than the speed of light, you can also "use" your mind to slow down time, travel through time and also slow down your ageing process. Before I say anything, let me make it clear that I'm neither being biased towards nor am I trying to promote any religion, I just want to share whatever I've read so far - There are many REAL Hindu saints (not the ones on TV) who advocate this theory, they say that death is something that should not be taken for granted, rather you should fight against it (http://en.wikipedia.org/wiki/Ramalinga_Swamigal). According to them, your life-span depends on the rate at which you breathe - the slower you breathe, the longer you live. Many saints in Hindu mythology, have lived in terms of multiples of hundreds of years. Many books even say there are archaeological evidences to support these facts. But honestly, I've never taken the pains to find out citations for them. nevertheless, its always interesting to read such stuff.


I think there's a fundamental flaw in your logic there.

If I put tarantula behind your sofa, then we can say the probability of there being a tarantula behind your sofa is pretty much 1. If you have 5 sofas in your house, then the probability of there being a tarantula behind a random sofa in your house is 1/5.

However, it doesn't follow that the probability of finding a tarantula behind any sofa is 1/5. All we can say about that is that it's non-zero.


So much left to explore.. So beautiful..

BTW, the name of the planetarium reminded me at first of Hadden. If you've read Contact, you'll understand what that name means.


We haven't even started exploring anything. Not even our own planet.

In universe or galactic terms we simply don't even register.


I feel so lowbrow, but sometimes a catchy toon that appeals to a wide audience can convey more than one might imagine: https://www.youtube.com/watch?v=f_J5rBxeTIk


Why is the current furthest mapping not in all directions? Is that because of the north and south poles?


Can someone explain why there are large sections of the universe that are unmapped?


Obscured, mostly by our own galaxy.


since we are on the "space" subject and I dont feel its worth new HN thread, but same time would love to pick up your brain; what do we see here? dust on a lenses???

http://www.youtube.com/watch?v=yjjftMK2HHM

appreciate your comments




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