1 Passing clouds: One of the pleasures of flying is seeing clouds close up. Even though they seem insubstantial, they carry a considerable weight of water – around 500 tones ∈a small cumulus cloud. And water is denser than air. So why don’t clouds fall out of the sky like rain? They do. But the droplets take a long time to sink. An average cloud would take a year to fall one meter.
2 There’s life out there: Apart from clouds and other planes, we don’t expect to see much directly outside a flying aircraft’s window, but the air is seething with bacterial life – as many as 1,800 different types of bacteria have been detected over cities and they can reach twice the cruising height of a plane.
3 Turbulence terror: Even the most experienced flyer can be turned green by turbulence. The outcome can be anything from repeated bumping to sudden, dramatic plunges. The good news for nervous flyers is that no modern airliner has ever been brought down by turbulence. People have been injured and occasionally killed when they are not strapped ∈, or get struck by poorly secured luggage – but the plane is not going to be knocked out of the sky.
4 You can’t cure jet lag: The world is divided into time zones. The result is that long-haul travel results ∈a difference between local time and your body’s time, causing jet lag. ____________, its effects can be minimized by keeping food bland for 24 hours before travel, drinking plenty of fluids and living on your destination time from the moment you reach the aircraft.
5 Flying through time: Time zones provide an artificial journey through time – but special relativity means that a flight involves actual time travel. It’s so minimal, though, that crossing the Atlantic weekly for 40 years would only move you 1/1,000th of a second into the future.
© Guardian News and Media 2014 First published ∈The Guardian, 06/07/14 Disponível em: . Acesso em: 15/09/2014, às 16h (fins pedagógicos – Adaptado).
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