10 Facts About the Internet's Undersea Cables

In describing the system of wires that comprises the Internet, Neal Stephenson once compared the earth to a computer motherboard. From telephone poles suspending bundles of cable to signs posted warning of buried fiber optic lines, we are surrounded by evidence that at a basic level, the Internet is really just a spaghetti-work of really long wires. But what we see is just a small part of the physical makeup of the net. The rest of it can be found in the coldest depths of the ocean. Here are 10 things you might not know about the Internet’s system of undersea cables.

1. CABLE INSTALLATION IS SLOW, TEDIOUS, EXPENSIVE WORK.

Reuters/Landov

Ninety-nine percent of international data is transmitted by wires at the bottom of the ocean called submarine communications cables. In total, they are hundreds of thousands of miles long and can be as deep as Everest Is tall. The cables are installed by special boats called cable-layers. It’s more than a matter of dropping wires with anvils attached to them—the cables must generally be run across flat surfaces of the ocean floor, and care is taken to avoid coral reefs, sunken ships, fish beds, and other ecological habitats and general obstructions. The diameter of a shallow water cable is about the same as a soda can, while deep water cables are much thinner—about the size of a Magic Marker. The size difference is related to simple vulnerability—there’s not much going on 8000 feet below sea level; consequently, there’s less need for galvanized shielding wire. Cables located at shallow depths are buried beneath the ocean floor using high pressure water jets. Though per-mile prices for installation change depending on total length and destination, running a cable across the ocean invariably costs hundreds of millions of dollars.

2. SHARKS ARE TRYING TO EAT THE INTERNET.

There’s disagreement as to why, exactly, sharks like gnawing on submarine communications cables. Maybe it has something to do with electromagnetic fields. Maybe they’re just curious. Maybe they’re trying to disrupt our communications infrastructure before mounting a land-based assault. (My theory.) The point remains that sharks are chewing on the Internet, and sometimes damage it. In response, companies such as Google are shielding their cables in shark-proof wire wrappers.

3. THE INTERNET IS AS VULNERABLE UNDERWATER AS IT IS UNDERGROUND.

It seems like every couple of years, some well-meaning construction worker puts his bulldozer in gear and kills Netflix for the whole continent. While the ocean is free of construction equipment that might otherwise combine to form Devastator, there are many ongoing aquatic threats to the submarine cables. Sharks aside, the Internet is ever at risk of being disrupted by boat anchors, trawling by fishing vessels, and natural disasters. A Toronto-based company has proposed running a cable through the Arctic that connects Tokyo and London. This was previously considered impossible, but climate change and the melting ice caps have moved the proposal firmly into the doable-but-really-expensive category.

4. CONNECTING THE WORLD THROUGH UNDERSEA CABLES ISN'T EXACTLY NEW.

In 1854, installation began on the first transatlantic telegraph cable, which connected Newfoundland and Ireland. Four years later the first transmission was sent, reading: “Laws, Whitehouse received five minutes signal. Coil signals too weak to relay. Try drive slow and regular. I have put intermediate pulley. Reply by coils.” This is, admittedly, not very inspiring. (“Whitehouse” referred to Wildman Whitehouse, the chief electrician of the Atlantic Telegraph Company, who we’ve discussed previously.) For historical context: During those four years of cable construction, Charles Dickens was still writing novels; Walt Whitman published Leaves of Grass; a small settlement called Dallas was formally incorporated in Texas; and Abraham Lincoln, candidate for the U.S. Senate, gave his “House Divided” speech.

5. SPIES LOVE UNDERWATER CABLES.

During the height of the Cold War, the USSR often transmitted weakly encoded messages between two of its major naval bases. Strong encryption was a bother—and also overkill—thought Soviet officers, as the bases were directly linked by an undersea cable located in sensor-laden Soviet territorial waters. No way would the Americans risk World War III by trying to somehow access and tap that cable. They didn’t count on the U.S.S. Halibut, a specially fitted submarine capable of slipping by Soviet defenses. The American submarine found the cable and installed a giant wiretap, returning monthly to gather the transmissions it had recorded. This operation, called IVY BELLS, was later compromised by a former NSA analyst named Ronald Pelton, who sold information on the mission to the Soviets. Today, tapping submarine communications cables is standard operating procedure for spy agencies.

6. GOVERNMENTS ARE TURNING TO SUBMARINE CABLES TO AVOID SAID SPIES.

With respect to electronic espionage, one big advantage held by the United States is the key role its scientists, engineers, and corporations played in inventing and building large parts of the global telecommunications infrastructure. Major lines of data tend to cross into American borders and territorial water, making wiretapping a breeze, relatively speaking. When documents stolen by former NSA analyst Edward Snowden came to light, many countries were outraged to learn the extent to which American spy agencies were intercepting foreign data. As a result, some countries are reconsidering the infrastructure of the Internet itself. Brazil, for example, has launched a project to build a submarine communications cable to Portugal that not only bypasses the United States entirely, but also specifically excludes U.S. companies from involvement.

7. SUBMARINE COMMUNICATIONS CABLES ARE FASTER AND CHEAPER THAN SATELLITES.

There are well over a thousand satellites in orbit, we’re landing probes on comets, and we’re planning missions to Mars. We’re living in the future! It just seems self-evident that space would be a better way to virtually “wire” the Internet than our current method of running really long cables-slash-shark-buffets along the ocean floor. Surely satellites would be better than a technology invented before the invention of the telephone—right? As it turns out, no. (Or at least, not yet.) Though fiber optic cables and communications satellites were both developed in the 1960s, satellites have a two-fold problem: latency and bit loss. Sending and receiving signals to and from space takes time. Meanwhile, researchers have developed optical fibers that can transmit information at 99.7 percent the speed of light. For an idea of what the Internet would be like without undersea cables, visit Antarctica, the only continent without a physical connection to the net. The continent relies on satellites, and bandwidth is at a premium, which is no small problem when one considers the important, data-intensive climate research underway. Today, Antarctic research stations produce more data than they can transmit through space.

8. FORGET CYBER-WARFARE—TO REALLY CRIPPLE THE INTERNET, YOU NEED SCUBA GEAR AND A PAIRE OF WIRE CUTTERS.

The good news is that it’s hard to cut through a submarine communications cable, if only because of the thousands of very lethal volts running through each of them. The bad news is that it is possible, as seen in Egypt in 2013. There, just north of Alexandria, men in wetsuits were apprehended having intentionally cut through the South-East-Asia-Middle-East-West-Europe 4 cable, which runs 12,500 miles and connects three continents. Internet speeds in Egypt were crippled by 60 percent until the line could be repaired.

9. UNDERWATER CABLES ARE NOT EASY TO REPAIR, BUT AFTER 150 YEARS, WE'VE LEARNED A TRICK OR TWO.

If you think replacing that one Ethernet cable you can’t quite reach behind your desk is a pain, try replacing a solid, broken garden hose at the bottom of the ocean. When a submarine cable is damaged, special repair ships are dispatched. If the cable is located in shallow waters, robots are deployed to grab the cable and haul it to the surface. If the cable is in deep waters (6500 feet or greater), the ships lower specially designed grapnels that grab onto the cable and hoist it up for mending. To make things easier, grapnels sometimes cut the damaged cable in two, and repair ships raise each end separately for patching above the water.

10. THE INTERNET'S UNDERSEA BACKBONE IS BUILT TO LAST FOR 25 YEARS.

As of 2014, there are 285 communications cables at the bottom of the ocean, and 22 of them are not yet in use. These are called "dark cables." (Once they’re switched on, they’re said to be “lit.”) Submarine cables have a life expectancy of 25 years, during which time they are considered economically viable from a capacity standpoint. Over the last decade, however, global data consumption has exploded. In 2013, Internet traffic was 5 gigabytes per capita; this number is expected to reach 14 gigabytes per capita by 2018. Such an increase would obviously pose a capacity problem and require more frequent cable upgrades. However, new techniques in phase modulation and improvements in submarine line terminal equipment (SLTE) have boosted capacity in some places by as much as 8000 percent. The wires we have are more than ready for the traffic to come.

10 Rad Gifts for Hikers

Greg Rosenke/Unsplash
Greg Rosenke/Unsplash

The popularity of bird-watching, camping, and hiking has skyrocketed this year. Whether your gift recipients are weekend warriors or seasoned dirtbags, they'll appreciate these tools and gear for getting most out of their hiking experience.

1. Stanley Nesting Two-Cup Cookset; $14

Amazon

Stanley’s compact and lightweight cookset includes a 20-ounce stainless steel pot with a locking handle, a vented lid, and two insulated 10-ounce tumblers. It’s the perfect size for brewing hot coffee, rehydrating soup, or boiling water while out on the trail with a buddy. And as some hardcore backpackers note in their Amazon reviews, your favorite hiker can take the tumblers out and stuff the pot with a camp stove, matches, and other necessities to make good use of space in their pack.

Buy it: Amazon

2. Osprey Sirrus and Stratos 24-Liter Hiking Packs; $140

Amazon

Osprey’s packs are designed with trail-tested details to maximize comfort and ease of use. The Sirrus pack (pictured) is sized for women, while the Stratos fits men’s proportions. Both include an internal sleeve for a hydration reservoir, exterior mesh and hipbelt pockets, an attachment for carrying trekking poles, and a built-in rain cover.

Buy them: Amazon, Amazon

3. Yeti Rambler 18-Ounce Bottle; $48

Amazon

Nothing beats ice-cold water after a summer hike or a sip of hot tea during a winter walk. The Yeti Rambler can serve up both: Beverages can stay hot or cold for hours thanks to its insulated construction, and its steel body (in a variety of colors) is basically indestructible. It will add weight to your hiker's pack, though—for a lighter-weight, non-insulated option, the tried-and-true Camelbak Chute water bottle is incredibly sturdy and leakproof.

Buy it: Amazon

4. Mappinners Greatest 100 Hikes of the National Parks Scratch-Off Poster; $30

Amazon

The perfect gift for park baggers in your life (or yourself), this 16-inch-by-20-inch poster features epic hikes like Angel’s Landing in Zion National Park and Half Dome in Yosemite National Park. Once the hike is complete, you can scratch off the gold foil to reveal an illustration of the park.

Buy it: Amazon

5. National Geographic Adventure Edition Road Atlas; $19

Amazon

Hikers can use this brand-new, updated road atlas to plan their next adventure. In addition to comprehensive maps of all 50 states, Puerto Rico, Canada, and Mexico, they'll get National Geographic’s top 100 outdoor destinations, useful details about the most popular national parks, and points on the maps noting off-the-beaten-path places to explore.  

Buy it: Amazon

6. Adventure Medical Kits Hiker First-Aid Kit; $25

Amazon

This handy 67-piece kit is stuffed with all the things you hope your hiker will never need in the wilderness. Not only does it contain supplies for pain, cuts and scrapes, burns, and blisters (every hiker’s nemesis!), the items are organized clearly in the bag to make it easy to find tweezers or an alcohol wipe in an emergency.

Buy it: Amazon

7. Hiker Hunger Ultralight Trekking Poles; $70

Amazon

Trekking poles will help increase your hiker's balance and stability and reduce strain on their lower body by distributing it to their arms and shoulders. This pair is made of carbon fiber, a super-strong and lightweight material. From the sweat-absorbing cork handles to the selection of pole tips for different terrain, these poles answer every need on the trail. 

Buy it: Amazon

8. Leatherman Signal Camping Multitool; $120

Amazon

What can’t this multitool do? This gadget contains 19 hiking-friendly tools in a 4.5-inch package, including pliers, screwdrivers, bottle opener, saw, knife, hammer, wire cutter, and even an emergency whistle.

Buy it: Amazon

9. RAVPower Power Bank; $24

Amazon

Don’t let your hiker get caught off the grid with a dead phone. They can charge RAVPower’s compact power bank before they head out on the trail, and then use it to quickly juice up a phone or tablet when the batteries get low. Its 3-inch-by-5-inch profile won’t take up much room in a pack or purse.

Buy it: Amazon

10. Pack of Four Indestructible Field Books; $14

Amazon

Neither rain, nor snow, nor hail will be a match for these waterproof, tearproof 3.5-inch-by-5.5-inch notebooks. Your hiker can stick one in their pocket along with a regular pen or pencil to record details of their hike or brainstorm their next viral Tweet.

Buy it: Amazon

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Asteroid, Meteor, Meteorite, and Comet: What's the Difference?

A mosaic image of asteroid Bennu
A mosaic image of asteroid Bennu
NASA's Marshall Space Flight Center, Flickr // CC BY-NC 2.0

By Sabrina Stierwalt, Ph.D., Quick and Dirty Tips

Adding up all of the mass in every asteroid in our entire solar system totals only less than the mass of our moon. Despite their small physical size, however, these space rocks offer important clues as to how our solar system formed. The terms asteroid, meteor, meteorite, and even comet are often used interchangeably ... but what is the difference?

What is an asteroid?

Asteroids are rocky objects smaller than planets that are left over from the formation of our solar system. When the cloud of gas and dust collapsed to form our sun, much of the remaining material went into forming the rocky terrestrial and gas giant planets orbiting our star. Smaller dust fragments that never made their way into planets are left behind as asteroids.

Of the millions of known asteroids, the largest is Ceres, 584 miles (940 kilometers) wide, although Ceres has been recently reclassified as a dwarf planet. Luckily we do not expect to cross paths with this Texas-sized solar system body any time soon. NASA tracks a subset of asteroids, called "near Earth objects" or NEOs, whose trajectories have been nudged by the gravitational push and pull of nearby planets enough so that they may pass close to Earth.

Thanks to infrared surveys of the sky like NASA’s WISE and NEOWISE missions, we know of roughly 1000 near-Earth asteroids that are larger than 0.6 miles across (or 1000 meters) and 1500 more that are between a third of a mile and 0.6 miles across (from 500 to 1000 meters). Smaller near-Earth asteroids, both known to exist and predicted based on statistical analysis, number in the 18,000s.

Most are not round like planets but rather irregular in shape, sometimes due to repeated impacts over time. They are also known to orbit each other, making their way around the sun in pairs or small groups. They are not large enough to hold onto their own atmospheres and their compositions vary, mostly due to the location where they were formed, in particular how far away they were from the sun when they originated.

Most asteroids reside in the asteroid belt, the space between the orbits of Mars and Jupiter, most likely because the gravitational pull of Jupiter prevented them from accumulating into a larger planetary system. Some asteroids are also found in the orbital paths of planets like Earth. Until recently all known asteroids orbited our sun as members of our solar system, but that changed in October 2017 when astronomers discovered the first interstellar visitor just passing through our solar neighborhood. Named 'Oumuamua, which comes from the Hawaiian word for “scout,” the asteroid has an unusual elongated shape (800 by 100 feet in size) and is moving too fast to be captured by our sun’s gravitational pull. That means 'Oumuamua will eventually leave us and continue on its journey through interstellar space.

What is a comet?

Comets are also composed of material left over from the formation of our solar system and formed around the same time as asteroids. However, asteroids formed toward the inner regions of our solar system where temperatures were hotter and thus only rock or metal could remain solid without melting. Comets formed at farther distances from the Sun, beyond what we call the frost or snow line and past the orbits of Mars and Jupiter, where temperatures were low enough for water to freeze.

Comets are thus chunks of frozen gas, rock, ice, and dust that orbit our sun, earning them the nickname of dirty snowballs. They are identified by their tails which consist of trailing jets of gas and dust that has been melted off as a comet approaches too close to the sun.

What is a meteor and a meteorite?

A meteor is simply an asteroid that attempts to land on Earth but is vaporized by the Earth’s atmosphere. The resistance on the rock due to the Earth’s atmosphere causes its temperature to rise. We sometimes see the glowing hot air created by these burning meteors and dub them “shooting stars.” Meteor showers occur when the Earth passes by many meteors at once. For example, if chunks of a comet melt off as it passes close to the sun, this debris can be left behind to later dazzle us Earthlings with a meteor shower.

Meteorites are meteors that survive the dive through the Earth’s atmosphere and manage to land on the surface of our planet. They are typically composed of either iron or stone, i.e. a mix of oxygen, silicon, magnesium, iron, and other elements.

Studying asteroids helps us understand the formation of our solar system and how our planet came to be. We don’t just have to wait for meteorites to find us to know more about their composition, however. The OSIRIS-Rex mission to the asteroid Bennu aims to take samples from the asteroid and bring them back to Earth. You can learn more about why Bennu was chosen for such a special mission on the OSIRIS-Rex mission page.

A version of this article was originally published on Quick and Dirty Tips as Asteroid, Meteor, Meteorite, and Comet: What's the Difference?
Read more from Quick and Dirty Tips.

About the author

Dr. Sabrina Stierwalt earned a Ph.D. in astronomy and astrophysics from Cornell University and is now a professor of physics at Occidental College.