The Panama Canal +5

The Luxor in Las Vegas - very powerful spotlight. Here is some information from AN ACTUAL ASTRONAUT in an article by science writer Robert Britt: There is a longstanding myth that the Great Wall of China is the only man made object visible from space. It and several variations on the theme are great fodder for water cooler arguments. In reality, many human constructs can be seen from Earth orbit. Shuttle astronauts can see highways, airports, dams and even large vehicles from an Earth orbit that is about 135 miles (217 kilometers) high. Cities are clearly distinct from surrounding countryside, and that's true even from the higher perch of the International Space Station, which circles the planet at about 250 miles (400 kilometers) up. "You can see an awful lot from space," says astronaut Ed Lu, the science officer of Expedition Seven aboard the station. "You can see the pyramids from space, especially with a pair of binoculars. They are a little difficult to pick out with just your eyes." Egyptian pyramids have been photographed from space several times with standard digital cameras and high-powered lenses. The largest pyramid at Giza, on the outskirts of Cairo, is 745 feet (227 meters) wide and 449 feet (137 meters) tall. "With binoculars you can see an awful lot of things," Lu wrote via e-mail in fielding a question from an Earthbound space fan. "You can see roads. You can see harbors. You can even see ships; very large tankers on the ocean we can see using the binoculars." There are some surprises, too. "You can see airplane contrails, and occasionally at the end of an airplane contrail, you will see a glint of sunlight off the airplane," Lu says. "And very occasionally, you do see other satellites go by. It is kind of a neat thing to see." There are of course places in space from which you can't notice how humans have sculpted the planet. Apollo astronauts could not make out manmade features from the Moon, for example. And from Mars, Earth would appear to the naked eye as nothing but a bright "star" in the night sky. So what about the Great Wall of China? "You can see the Great Wall," Lu says. But it's less visible than a lot of other objects. And you have to know where to look. In fact stretches of the wall aren't even visible from China. They've been buried by sand for centuries. NASA has used space-based radar to map out hidden parts of the ancient structure. Lu is trying to get a picture of it, too, with a digital camera. "The weather hasn't cooperated," he says. "There has been a lot of clouds and haze over that area since I've been trying. But I hope to be successful before I come back down." This article is part of SPACE.com's weekly Mystery Monday series.

The visibility of the great wall from space is largely a myth. There are some claims that it can be seen from very low orbit, but basically once you get low enough to see it, two things are true: 1. you are likely no longer technically in space 2. you can see LOTS and LOTS of other man made structures, like highways and cities.

The river that flows through the Grand Canyon?

my house and yours is visible from space via spy satellite

Pam Anderson's boobs.

You can't see the Great Wall from space, that's a myth. The width of the wall is only a few dozen feet. There are structures that are several times that size that you cannot see from space. Think about it. To quote Mensan, the Panama Canal IS a man-made construction that can be seen from space.

Thats a myth, if you could see the great wall from space you would also be able to see many roads also

No man-made objects can be seen from space..

The pyramids of Egypt.

Check your facts.It's a myth. One thing that can be seen from space however, is Bill Gates' wad of cash!!

hadrians wall and the junk in my yard!

The light from the black pyramid in vegas.

I heard the vegas strip cuz its so bright

Jordan's breast implants.

My ex-wife's *ss.

pyramids

Bill Clinton's ego.

The California aqueduct.

I think hoover dam.

Kamlesh P. Lulla, NASA's chief scientist for Earth observation at Johnson Space Center in Houston: "From space you can see a lot of things people have made. Perhaps most visible from low Earth orbit are cities at night. Cities can be seen during the day too, as can major roadways and bridges, airports, dams and reservoirs." These are two pictures of the pyramids and a portion of the Great Wall of China. Pyramids left of centre in image. Great wall right side of image

There is a longstanding myth that the Great Wall of China is the only manmade object that is visible by an observer in space. However, this is a myth! The truth is that many human constructs can be seen from Space. If we take "space" to mean a low Earth orbit such as the one traveled by the Space Shuttle (roughly 160 to 350 miles above Earth), then an observer from the space shuttle with the aid of binoculars can easily see objects such as: airports, highways, bridges, components of the Kennedy Space Center and, even large ocean tankers. In addition, the largest cities are clearly visible to the human eye. Go to NASA's Earth From Space photographic archive located at http://earth.jsc.nasa.gov/sseop/efs/ and see for yourself pictures that have been taken from low orbit reveal human-built structures such as highways, airports, bridges, dams, and components of the Kennedy Space Center. At 250 miles (400 KM) high, the altitude of the International Space Station, one can no longer see the outline of neither highways nor anything the size of airports. However, cities are still visible. If the observer is on the surface of the moon at a rough distance of 237,000 miles, then not a single man-made object can be seen with or with a set of binoculars. Apollo 12 astronaut Alan Bean said, “The only thing you can see from the moon is a beautiful sphere, mostly white (clouds), some blue (ocean), patches of yellow (deserts), and every once in a while some green vegetation. No man-made object is visible on this scale. In fact, when first leaving earth's orbit and only a few thousand miles away, no man-made object is visible at that point either." If the observer is now located on the surface of Mars, the Earth itself would look like bright star in the sky. Much in the same way Venus and Mars looks to us.