5 Man-Made Things You Can See from Space (Plus One You Really Can’t)

Nicole Stott, via Universe Today

Which of mankind’s marvels can we actually spot from the final frontier? This question calls for a little perspective. Space is big. Sure, you might be able to gaze at the Amazon River while hovering a few hundred miles above sea level. But from the moon, you could barely even make out the continents! And our whole planet looks like nothing more than a dinky blue splotch from Mars’ surface. Still, astronauts traveling in Low Earth Orbit or on board the International Space Station can see quite a bit using nothing but their naked eyes.

1. The Great Pyramids at Giza

Some squinting may be required to spy Egypt’s greatest monuments in this picture snapped by astronaut Nicole Stott. If you’re really lost, look for a pair of triangular shadows near the center…

2. Bridges

Chris Hadfield, via Huffington Post

Long bridges crossing over straits stick out like a sore thumb. However, identifying them can be a pain. Last year, astronaut Chris Hadfield caught a glimpse of what he thought was the Golden Gate, but may have really been a less-glamorous bay area counterpart.

3. Lonely Desert Roads

Chris Hadfield, via Universe Today

As Hadfield explains, desert highways look like “straight human [lines] drawn onto incredibly rough terrain," making them rather noticeable.

4. Cities at Night


Space-bound explorers have taken hundreds of nocturnal photos over various urban centers. Here’s a helpful interactive gallery. Go look up a metro area near you.

5. The Greenhouses of Almería

Wikimedia Commons

A sprawling sea of plastic greenhouses covers over 64,000 acres in southeastern Spain. Tons of fruits and veggies (tomatoes, cucumbers, peppers, etc.) are produced here, generating $1.5 billon in revenue every year. 

Kinda, Sorta, Not Really Visible: The Great Wall of China

NASA, via Universe Today 

Let’s get a few things straight. Can you see this ancient marvel while walking on the moon, as many claim? No way. Again, people really can’t see much of any detail Earth-wise from up there. On a similar note, it’s also effectively out of sight for the International Space Station’s crewmembers.

Another persistent rumor holds that China’s Great Wall is the only man-made structure that’s visible from space. As we’ve seen, this is nonsense. This demonstrably-false idea dates back to at least the 1930s, long before manned space missions started taking off!

Yet, one vitally important question remains: Where does space start anyway? By most international standards (even though a certain Air Force disagrees), the boundary between Earth’s jurisdiction and outer space rests approximately 62 miles above sea level.

From this height, the Great Wall is technically visible, at least according to astronauts Eugene Cernan and Ed Lu. However, it’s not exactly conspicuous. Even under the best solar and weather conditions, this landmark is virtually indistinguishable from neighboring rivers and mountains. Therefore, most space-travelers miss the Wall entirely.

In fact, one person who definitely didn’t see it was China’s first astronaut, Yang Liwei. “The scenery was very beautiful,” Liwei said after returning to Earth in 2003. “But I didn’t see the Great Wall.”

ESA/Herschel/SPIRE; M. W. L. Smith et al 2017
Look Closely—Every Point of Light in This Image Is a Galaxy
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017

Even if you stare closely at this seemingly grainy image, you might not be able to tell there’s anything to it besides visual noise. But it's not static—it's a sliver of the distant universe, and every little pinprick of light is a galaxy.

As Gizmodo reports, the image was produced by the European Space Agency’s Herschel Space Observatory, a space-based infrared telescope that was launched into orbit in 2009 and was decommissioned in 2013. Created by Herschel’s Spectral and Photometric Imaging Receiver (SPIRE) and Photodetector Array Camera and Spectrometer (PACS), it looks out from our galaxy toward the North Galactic Pole, a point that lies perpendicular to the Milky Way's spiral near the constellation Coma Berenices.

A close-up of a view of distant galaxies taken by the Herschel Space Observatory
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017

Each point of light comes from the heat of dust grains between different stars in a galaxy. These areas of dust gave off this radiation billions of years before reaching Herschel. Around 1000 of those pins of light belong to galaxies in the Coma Cluster (named for Coma Berenices), one of the densest clusters of galaxies in the known universe.

The longer you look at it, the smaller you’ll feel.

[h/t Gizmodo]

Why Do Astronauts Use Space Pens Instead of Pencils?

by Alex Carter

It's often said that NASA spent millions of dollars developing a pen that could write in zero gravity, while the Russians just used pencils. It was a warning about looking for a high-tech solution to a mundane problem, of American excess vs. Russian sensibility.

It's also entirely false.

To understand why NASA was so keen on a workable space pen, you have to understand that the pencil is not suited for space travel. The problem is that they have a habit of breaking, shattering, and leaving graphite dust behind. The wood, too, can make it a serious fire risk in the pressurized, oxygen-rich capsule. All of these common issues become life-threatening hazards in space.

Still, there were attempts to bring pencils into space. In 1965, the agency famously ordered 34 specially designed mechanical pencils in hopes of finding the perfect writing tool for astronauts. But at $128 each, they weren't exactly cheap, and it only got worse when the public got wind of the price. Thankfully, an alternative was not too far behind.

Astronaut Walt Cunningham, pilot of the Apollo 7 mission, uses the Fisher Space Pen while in flight.
Astronaut Walt Cunningham, pilot of the Apollo 7 mission, uses the Fisher Space Pen while in flight.

The Space Pen was invented by Paul Fisher, head of Fisher Pen Company. Unlike a typical pen, the Fisher Space Pen uses compressed nitrogen to force ink out of the nozzle, instead of using gravity to make it flow. This made it the ideal device for writing in space, while upside down, or submerged underwater. It wrote crisp and clean, without the safety concerns of a pencil.

Fisher contacted NASA to give his pens a try in 1965 and in 1967, after months of testing, they were impressed enough to bulk buy 400 of them for future missions. Contrary to those urban legends, NASA didn't commission the pen or contribute any funding to it. The Soviets soon ditched their grease pencils and were eventually buying the same Fisher pens as NASA, too. The price? After a 40 percent discount from Fisher, both space agencies were paying $2.39 a pen.

The Fisher Space Pens made their debut in 1968 on the Apollo 7 mission and have been involved in all manned missions since.

So, the short reason is that astronauts only used pencils when they were waiting for something better to come along. As soon as it did, they switched and never looked back. Even the Russians thought it was a good idea.

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