Which is the largest man made structure on earth?

Answer 1

The Great Wall of China is the largest manmade structure in terms of overall volume and length. It can be seen from space.

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It can't be seen from space. Astronauts have deliberately tried. It is only a few metres wide!

Answer 2

There are two very large man-made structures that the question refers to. They are the Great Wall of China and Panama Canal. This is because of their size.

It actually depends what you define as "outer space". From low orbit, many things can be seen (cities, airports, farms), but even NASA says "The Great Wall can barely be seen from the Shuttle" and that at an altitude of a few thousand miles no man-made objects can be seen. Tne problem with the Wall is that it is thin and its materials blend in with the surrounding terrain. The problem with the Panama Canal is that except for the city-block-sized dams and locks, it looks like any other system of rivers and lakes.

Weather is also a key factor in any observation from space. This applies to Earth as well as other planets.

Even More Visible

While traveling across the night-side of the planet, those in orbit can clearly see the illumination of electric lights from major cities.

Answer 3

Currently, the largest man-made structure in space is the International Space Station, orbiting in Low Earth Orbit. Currently under construction, and due to be finished in 2011, it will be approximately 400 tons, with a pressurized internal space of approximately 1000m2.

Answer 4

The Voyager 1 space probe.