What's the Longest Bridge in the World?

Getty Images
Getty Images

Gephyrophobia sufferers should turn away now. We’re going to be discussing the longest bridge in the world, and if you have a fear of these water-crossing constructs, some anxiety is going to be inevitable. (Alternately, you might use it as a guide for where not to go.)

Bridges are modern marvels of engineering. Spanning over bodies of water, they can stretch for as little as a few dozen feet to several miles, facilitating the transport of vehicles from one place to another without the need to hop into a boat. Some are suspension bridges, knots of wire and steel without bracing underneath; others are segmented, with support throughout. When someone ponders what the longest bridge in the world is, they may want to consider what kind of bridge they’re talking about.

The Guinness Book of World Records ran into this semantics issue in 2011, when China finished construction on the Jiaozhou Bay Bridge, also known as the Qingdao Haiwan Bridge, near the Shandong Peninsula. The bridge spans an incredible 26.4 miles, with 5200 pillars supporting it along the way. The bridge—which took four years to complete—was so sprawling that it beat the previous record holder, Louisiana’s Lake Pontchartrain Causeway, by more than two miles. Said to be earthquake- and typhoon-proof, it’s one impressive structure.

But the Lake Pontchartrain Causeway is still significant. It’s 23.8 miles over continuous water, while the Jiaozhou Bay Bridge utilizes sea tunnels for parts of the structure and contains multiple lanes. As a result, Guinness refers to the Jiaozhou as the largest “aggregate” bridge in the world, while the Causeway is still believed to be the longest continuous bridge over water.

Those are impressive numbers, but if you don’t require bridges to be needed to navigate over bodies of water, then the longest bridge in the world might be the Dayang-Kunshan Grand Bridge in China. Part of a high-speed railway system, that bridge stretches for 104.2 miles and provides train transport between Shanghai and Nanjing.

If a bridge only impresses—or terrifies—you based on it being the longest bridge in the world without any underlying support, then you might want to investigate the Pearl Bridge beginning in Kobe, Japan. The central part of this 2.4 mile long bridge has 1.237 miles of uninterrupted span.

Of course, length isn’t necessarily directly correlated with the fear factor. If your curiosity over the longest bridge in the world is really over the scariest bridge in the world, you may want to avoid photos of Russia’s Kuandinsky Bridge. Barely wider than a car and with no guardrails, it’s almost a theme park ride, albeit one closed to the public—leaving only the very brave to risk crossing it.

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Are Any of the Scientific Instruments Left on the Moon By the Apollo Astronauts Still Functional?

Apollo 11 astronaut Neil Armstrong left the first footprint on the Moon on July 20, 1969.
Apollo 11 astronaut Neil Armstrong left the first footprint on the Moon on July 20, 1969.
Heritage Space/Heritage Images/Getty Images

C Stuart Hardwick:

The retroreflectors left as part of the Apollo Lunar Ranging Experiment are still fully functional, though their reflective efficiency has diminished over the years.

This deterioration is actually now delivering valuable data. The deterioration has multiple causes including micrometeorite impacts and dust deposition on the reflector surface, and chemical degradation of the mirror surface on the underside—among other things.

As technology has advanced, ground station sensitivity has been repeatedly upgraded faster than the reflectors have deteriorated. As a result, measurements have gotten better, not worse, and measurements of the degradation itself have, among other things, lent support to the idea that static electric charge gives the moon an ephemeral periodic near-surface pseudo-atmosphere of electrically levitating dust.

No other Apollo experiments on the moon remain functional. All the missions except the first included experiment packages powered by radiothermoelectric generators (RTGs), which operated until they were ordered to shut down on September 30, 1977. This was done to save money, but also because by then the RTGs could no longer power the transmitters or any instruments, and the control room used to maintain contact was needed for other purposes.

Because of fears that some problem might force Apollo 11 to abort back to orbit soon after landing, Apollo 11 deployed a simplified experiment package including a solar-powered seismometer which failed after 21 days.

This post originally appeared on Quora. Click here to view.

What Makes a Hotel Breakfast 'Continental'?

Hotels often offer a complimentary pastry and fruit breakfast.
Hotels often offer a complimentary pastry and fruit breakfast.
tashka2000/iStock via Getty Images

The continental breakfast, which is typically made up of pastries, fruit, and coffee, is often advertised by hotels as a free perk for guests. But why is it called continental, and why don’t patrons get some eggs and bacon along with it?

The term dates back to 19th century Britain, where residents referred to mainland Europe as “the continent.” Breakfast in this region was usually something light, whereas an English or American breakfast incorporated meat, beans, and other “heavy” menu options.

American hotels that wanted to appeal to European travelers began advertising “continental breakfasts” as a kind of flashing neon sign to indicate guests wouldn’t be limited to American breakfast fare that they found unappealing. The strategy was ideal for hotels, which saved money by offering some muffins, fruit, and coffee and calling it a day.

That affordability as well as convenience—pastries and fruit are shelf-stable, requiring no heat or refrigeration to maintain food safety—is a big reason continental breakfasts have endured. It’s also a carryover from the hybrid model of hotel pricing, where American hotels typically folded the cost of meals into one bill and European hotels billed for food separately. By offering a continental breakfast, guests got the best of both worlds. And while Americans were initially aghast at the lack of sausages and pancakes on offer, they’ve since come around to the appeal of a muffin and some orange juice to get their travel day started.

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