Why Is There a Leap Day?

Bychykhin_Olexandr/iStock via Getty Images
Bychykhin_Olexandr/iStock via Getty Images

At some point in elementary school, your science teacher probably explained to you that there are 365 days in a year because that’s how long it takes for Earth to complete one full rotation around the sun. What they might not have specified, however, is that it’s not exactly 365 days—it’s actually closer to 365.2421 days.

So, if we want our calendar year to begin right when Earth begins a new rotation around the sun, we have to account for (roughly) an extra quarter of a day each year, or one day every four years. History.com reports that the Egyptians had already been doing this for a while before Europe finally caught on in 46 B.C.E., when Roman dictator Julius Caesar and astronomer Sosigenes put their heads together to come up with what we now call the Julian calendar, which includes 12 months, 365 days, and an additional “leap day” every four years on February 29.

But rounding 0.2421 up to 0.25 each year created an issue, because it didn’t quite add up to a full day every four years—and that tiny discrepancy meant that after 128 years, the calendar year ended up starting a day before Earth had completed its rotation around the sun. By the 14th century, the calendar year was starting a whopping 10 days before Earth finished its orbit.

In 1582, Pope Gregory XIII sought to correct the error by suggesting that we simply skip a leap day every so often. His Gregorian calendar, which we still use today, mandates that we omit the leap day during years evenly divisible by 100 but not by 400. For instance, the year 2000 included a leap day because it’s divisible by 100 and 400; the year 2100, on the other hand, will not include a leap day, since it’s evenly divisible by 100, but not by 400.

Gregory XIII’s correction to Caesar’s overcorrection is itself a bit of an under-correction, so we’ll probably need to reevaluate our leap day protocol again in about 10,000 years.

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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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Does Pushing the Button at a Crosswalk Actually Do Anything?

Pressing this crosswalk button may or may not do something.
Pressing this crosswalk button may or may not do something.
David Tran/iStock via Getty Images

Since crosswalk signals rarely seem to give you the green light (or more accurately, the white, human-shaped light) right after you press the button, you may find yourself wondering if those buttons actually work. The potentially exasperating answer is this: It depends.

First and foremost, it’s important to understand that crosswalk buttons aren’t designed to have an immediate effect; they’re just supposed to tell the system that a person is waiting to cross. As CityLab explained, some systems won’t ever give pedestrians the crossing signal unless someone has pressed the button, while others are programmed to shorten the wait time for walkers when the button has been pressed. No matter what, the system still has to cycle through its other phases to give cars enough time to pass through the intersection, so you’ll probably still have to stand there for a moment.

During busy traffic times or under other extenuating circumstances, however, cities can switch the system to what’s known as “recall mode,” when pedestrian crossings are part of the cycle already and pressing the button quite literally changes nothing. Unfortunately, there’s no way to tell if a particular button is in recall mode, short of calling your city officials and asking an expert to come inspect it.

But if you feel like a button isn’t doing anything, there’s a pretty good chance it’s been permanently deactivated. As congestion has increased and the systems to manage it have become more advanced over the years, cities have moved away from using crosswalk buttons at all. In 2018, for example, CNN reported that only around 100 of New York City’s 1000 buttons were still functioning. Since actually removing the buttons from crosswalks would be a costly endeavor, cities have opted to leave them intact, just waiting to be pummeled by impatient pedestrians who don’t know any better.

What about 'close door' buttons on elevators, you ask? That depends, too.

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