How much space does the Chunnel enclose?
The 3 Gorges Dam is the answer I gave the last time I saw this question. I would have to think that it qualifies as man-man, even though it doesn’t have any real interior space.
The Seikan tunnel is slightly longer. At 53.9 km length and 10 m diameter, its volume is 4.2 million m[sup]2[/sup]. That’s just the main tunnel, and I think there’s a service tunnel that runs alongside it, but I don’t think it surpasses the Boeing Everett plant (13.3 million m[sup]2[/sup]).
The Three Gorges Dam uses 27.15 million m[sup]2[/sup] of cement, so if you’re talking about total volume of a man-made structure (and not internal space), I think that’s the winner. Unless you start including large systems or networks (e.g. “the US highway network”).
The problme with these types of quetsions is that nobody is ever able to define what they mean by ‘thing’.
The largest man made ‘object’ in the universe is without a doubt the bubble of radio tranmissions around the Earth, currently occupying a sphere about 200 light years across, and growing.
Beyond that it’s impossible to nail down. As other shave pointed out, cities could qualify, as could road systems. And o course we could say that if the citeis qualify and the roads that connect them then entire countries count. It’s almost impossible to draw a line that divides any man made ‘building’ form a collection buildings.
What about the bubble of visible light, generated by man-made fires?
(By the way, every instance of “m[sup]2[/sup]” in my above post should have been “m[sup]3[/sup]”. Sorry. I do know the difference.)
By way of comparison from above, here’s several objects at (nearly) the same scale :
Three Gorges Dam
Gezhouba Dam (below Three Gorges)
Boeing Plant (note that the roof is two colors, white on the right and slate gray on the left.)
London (Parliament Square)
orbital cloud of debris, or that junk satalite orbit.
Don’t know how it compares to the Boeing facility, and I can’t find any figures, but when it was opened, Hong Kong’s new Chek Lap Kok airport was touted as the largest enclosed space in the world. It’s a single “room”, 1.27 km long, very wide, but not that tall.
Would the physical odds and ends of the internet count?
Objection.
A hole is not an object, it is the abscence of an object.
I once read years ago that Lake Okeechobee in south Florida was the largest man-made thing and the only one visible from orbit.
Actually, there are quite a few manmade objects that are visible from space.
If Google Earth is to be believed, a lot of things are visible from space.
I’d also say that as big as the dams are, the lakes they create are far larger. They would have to be considered man made.
The quantity of stored human knowledge.
If you took the contents of the two largest libraries of the world, digitized all the books and saved them on DVD-ROM disks, it would occupy only 9 cubic meters*. It can be carried on a single 18-wheeler.
Even if you assume those two libraries contain 1% of the total human knowledge (others being in other countries’ libraries, film archives and digital storage), all of it would fit in 25 shipping containers. That’s one 1/4-mile long train.
*That’s assuming 300 million books, 500 pages per book, 100 kilobytes per page, and each DVD in a 3mm thick sleeve.
scr4 I said “The quantity of stored human knowledge.”
I did not say the minimal volumetric space in which you may be able to store it’s representation in.
I think the ‘visible from space’ claim means ‘visible with the naked eye’.
A little off topic, but I’ve heard it said that the Great Barrier Reef is the largest object made by living organisms (Ignoring, as noted in other posts, problem with “size” and “object” in sucha a statement).
How else do you propose to quantify the “quantity of stored human knowledge”, so it can be compared to the size of other man-made objects?
Recently, I’ve been hoping that Texas is just a figment of our collective imaginations, would that count, if true?