Consumer & Gadgets

Curbing indoor air pollution in India

Around the world, more than 3 billion people—nearly half the world's population—cook their food using solid fuels like firewood and charcoal on open fires or traditional stoves. This produces a lot of smoke, creating ...

Energy & Green Tech

How do lithium-ion batteries work?

The smartphone era is only just over a decade old, but the pocket-sized computers at the heart of that societal transformation are only really possible because of another technology: lithium-ion batteries.

Hardware

LG will smarten home appliances with eyes and ears

LG has made news headlines recently because now it has its own artificial intelligence chip. LG is out to impress with its own chip for smart home products—to make them even smarter.

Engineering

Researchers propose air conditioners as climate-change remedy

Scientists have an idea that could make you feel more like a green citizen than hedonist if you buy an air conditioner for your living quarters. There is a way that could use the units to fight climate change. OK, let us ...

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Earth's atmosphere

The Earth's atmosphere is a layer of gases surrounding the planet Earth that is retained by the Earth's gravity. It has a mass of about five quadrillion metric tons. Dry air contains roughly (by volume) 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.038% carbon dioxide, and trace amounts of other gases. Air also contains a variable amount of water vapor, on average around 1%. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night.

There is no definite boundary between the atmosphere and outer space. It slowly becomes thinner and fades into space. An altitude of 120 km (75 mi) marks the boundary where atmospheric effects become noticeable during atmospheric reentry. The Kármán line, at 100 km (62 mi), is also frequently regarded as the boundary between atmosphere and outer space. Three quarters of the atmosphere's mass is within 11 km (6.8 mi; 36,000 ft) of the surface.

This text uses material from Wikipedia, licensed under CC BY-SA