The Reason Behind Those Brightly Colored Balls Along Power Lines

If you've ever driven past those colorful balls strung up along a power line, you might have wondered about what purpose they serve—a thought that usually disappears as soon as the balls have faded from your rearview mirror. Though we sort of wish they were rogue holiday decorations local governments forgot to take down, the truth is that they’re actually used for aircraft safety.

According to electric utility company Edison International, the balls are called visibility marker balls (or just marker balls, for short), and they help make power lines more obvious to low-flying aircraft like planes and helicopters. Though you might not have realized it, you usually spot marker balls near mountain passes, deep valleys, major freeway crossings, and airports—all locations where aircraft tend to fly at low altitudes, running the risk of getting tangled up in the hard-to-see cables.

The Federal Aviation Administration regulates these marker balls and details their specifications in the Advisory Circular No. 70/7460-1L [PDF]. The diameter of the balls must be at least 36 inches on wires that cross canyons, lakes, and rivers, but the FAA allows 20-inch spheres on power lines fewer than 50 feet above ground level and within 1500 feet of an airport runway end. They should be spaced evenly at roughly 200-feet intervals along regular wires, and with less space (30- to 50-feet) intervals on wires near runway ends.

If there are fewer than four marker balls on a given wire, they should all be “aviation orange,” the fluorescent hue you probably associate with some communication towers. Otherwise, they should alternate between orange, white, and yellow to provide the highest level of visibility to approaching aircraft.

According to a 1983 article from United Press International, the marker balls first gained popularity in the early 1970s, when Arkansas’s then-governor Winthrop Rockefeller noticed electric wires whiz by as his aircraft started to land and decided something should be done to make them more obvious to pilots. The article also notes that the benefits go beyond aviation—the markers also help geese and boats steer clear of inconspicuous cables.

If you’re wondering by what magic the marker balls get installed on hard-to-reach power lines, it sometimes takes one helicopter and a very plucky technician. Check out the video below from T&D World to see exactly what that looks like. (The especially thrilling bit starts around 2:10.)

Now that one road-related mystery has been solved, find out the function of those black tubes sometimes stretched across the road.

[h/t Edison International]

Why Are Shower Doors in Hotel Rooms Getting Smaller?

sl-f/iStock via Getty Images
sl-f/iStock via Getty Images

Shower doors are shrinking in posh hotels, and minimalism is to blame, Condé Nast Traveler reports.

In lieu of hanging shower curtains or providing full shower doors, many newer hotels are opting for glass panels that cover only half the length of the shower. That’s frustrating for many travelers, who complain the growing trend is inconvenient and leaves bathroom floors sopping wet and slippery after shower use.

According to Condé Nast Traveler, the half-door trend began in European hotels in the 1980s. “A lot of it comes down to people trying to design hotel rooms with limited space,” boutique hotel designer Tom Parker told the magazine. “It’s about the swing of the shower door, because it has to open outward for safety reasons, like [if] someone falls in the shower. You have to figure out where the door swing’s going to go, make sure it’s not [hitting] the main door. It’s just about clearances.” A smaller door also has the added benefit of making the space appear larger than it really is, according to the magazine.

The trend is also connected to the birth of minimalist “lifestyle hotels,” which cater to a younger, hipper clientele that gravitates toward sleek lines and modern design. Plus, half-size glass doors are easier to clean than shower curtains, which tend to trap bacteria and need to regularly be replaced, which can add up to significant additional costs for a hotel.

Theoretically, even half-door showers are designed to minimize water spillage. Designers try to level the floors in bathrooms so water doesn’t pool in random areas, and they place shower heads and knobs in areas that are more protected by glass paneling. And where design doesn’t work, hotels try to pick up the slack.

“Hotels tend to mitigate the risks by offering non-slip interior shower mats, cloth bath mats for stepping out of the shower, grab bars, [and] open showers or no-sill showers which avoid having to step up and over the ledge,” designer Douglas DeBoer, founder and CEO of Rebel Design Group, told Condé Nast Traveler.

But the half-door trend still has yet to gain much love from hotel guests. “The older generation much, much prefers having a shower door,” Parker told Condé Nast Traveler. “I’m like a 70-year-old man at heart anyway. I like [a shower door] if it’s in keeping with the style of the rest of the room.”

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The Reason Why Daylight Saving Time Begins at 2 a.m.

Daylight saving time has been erasing 2 a.m. on and off since 1918.
Daylight saving time has been erasing 2 a.m. on and off since 1918.
Rawf8/iStock via Getty Images

If you happen to be awake and staring at your smartphone in the very early hours of the morning on Sunday, March 8, you’ll have the small pleasure of watching the time jump right from 1:59 a.m. to 3:00 a.m. Daylight saving time (DST), of course, is the reason you’re losing an hour of sleep—but why that hour, specifically?

As TIME explains, the United States first adopted DST in 1918 as a way to conserve energy during World War I, following the lead of both England and Germany. When choosing exactly when to make the switch, officials were looking for an hour that could easily disappear without wreaking havoc on people’s schedules across the nation. Since no Amtrak trains departed New York City on Sundays at 2 a.m., losing that hour seemed a little less consequential than any other.

“Sunday morning at 2 a.m. was when [a time change] would interrupt the least amount of train travel around the country,” Michael Downing, author of Spring Forward: The Annual Madness of Daylight Saving Time, told TIME.

The United States didn’t stick with daylight saving time after 1918—partially because so many farmers opposed it—but it did resurrect the tradition during World War II, and Congress formalized the practice in 1966 with the Uniform Time Act (which also created the time zones we use today).

The reason DST’s 2 a.m. start time has remained standard through the years isn’t just because it prevents confusion among late-night train passengers. Considering that most bars and restaurants are closed by then, and early shift-workers won’t be awake yet, it’s a pretty quiet hour across the board.

Wondering how daylight saving time will affect sunrise and sunset times in your area? Here’s a map for that.

[h/t TIME]

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