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Contrast this with the Hubble Deep Field image, which is an extremely tiny patch of the night sky. It’s sizeis equivalent to a tennis ball at a distance of 100 metres, or ~110 yards.

And my god, it’s full of stars. There’s endless detail in the universe, whether you zoom in, or zoom out.

See: https://upload.wikimedia.org/wikipedia/commons/6/69/NASA-HS2...



Each "star" in the Hubble Deep Field image is actually an entire galaxy... The vastness of the universe is difficult to comprehend.


I read Dragon's Egg recently, and one of the key leap from barbarian to civilization that the neutron star aliens make is (simplistically) to count past "many" and think of quantities / numbers abstractly.

Our ability to track distinct objects is impressive by our own standard, and we're pretty good at understanding "big" numbers, say somewhere between a million and a billion. But in the scale of things, we're much closer to the hunter knowing his kill will feed his tribe for many moons versus being a starfaring race.


Re "big" numbers, I can't help thinking of Richard Feynman's comment "There are 10^11 stars in the galaxy. That used to be a huge number. But it's only a hundred billion. It's less than the national deficit! We used to call them astronomical numbers. Now we should call them economical numbers."

The entire universe probably contains around 10^80 protons, yet Google's founders casually referred to the number 10^100 to indicate their ambitions for information processing.

A carbon atom is 0.3 nm in diameter, so only about 3.3 million can fit in 1 mm. There are well over twice the number of people in NYC!

All in all, numbers that describe the natural world aren't all that impressive compared to the human world.


> A carbon atom is 0.3 nm in diameter, so only about 3.3 million can fit in 1 mm.

Sure, but about 70 quintillion of them fit in 1 mm^3.


>The entire universe probably contains around 10^80 protons

The entire visible universe that is. It could well be infinite and hence contain a larger number of them.


What does it mean to say something "exists" but is not "observable"?


The inherent problem is that the universe has been transparent for a limited amount of time. Since this time the light from this era has been travelling in all kinds of directions, some of it in ours.

We can only see the light that has had time to reach us. Everything that is farther away than about a dozen billion lightyears is not visible.

Technically new stuff is always becoming visible to use, the visible universe expands naturally as new light reaches us.

Of course, the stuff is now farther away since the universe is expanding and at some point the expansion will likely overtake the speed of light and over some distance may have, which means beyond some distance we will never be able to see or know.

What is beyond the visible universe is quite unknown. We can't see it.


Skepticism. What's not observable now might become observable eventually.


Googol isn't the estimated ambition for Google's database, it's just the biggest number with a cute, short name.


Excellent comparison. Puts things into perspective


> All in all, numbers that describe the natural world aren't all that impressive compared to the human world.

But you're comparing mere cardinality with combinations and permutations. We know the latter always produces huge numbers.


> we're pretty good at understanding "big" numbers, say somewhere between a million and a billion.

When we stop and think about it, maybe. But try this experiment with a friend (or a few times with different friends): take a sheet of A4 or "letter" sized paper and a pencil, turn it in landscape orientation and mark the far left side of it with '0', and the far right side as '1B' telling them it's an even scale from zero to one billion, and ask them "without thinking about it just mark where a million would be." -- it's important to get a response from "the top of their head" to understand the difference between what we can recall, and what we habitually think. Most people are way off. If paper isn't handy use fingers and a large object you can touch - e.g. top edge of monitor or TV etc.


I asked someone. Their approach was to divide by half a few times. Looks like they made a good guess.


Dividing in half 10 times comes pretty close (976562), but kinda defeats the point of getting a spontaneous answer as the what they feel it would be. On a 1 meter scale the 1 million mark would be just 1mm along. On a piece of paper, it's virtually indistinguishable from the starting point.


Why would you use a million and a billion instead of 1 and 1000?


The point of the exercise is that many people don't really grok that a billion is a thousand times bigger than a million, - or rather just how much bigger a factor of 1000 actually is, when talking about big numbers that they're not as used to... no matter whether using paper, or a desk, or a wall for scale.


Depends on whether the scale is linear or logarithmic.


I should have specified linear instead of even.


That works by using "anchoring" by priming them with the length scale of the paper.


here is a perspective video: https://www.youtube.com/watch?v=q1mkjkTqg0Y


The star UY Scuti is 2,500,000,000 kilometres in diameter.

It would take light nearly 2.5hrs to travel that far.


One of better videos of this type. Anyone know what's the music from background? Hair raising.





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