And those electrons drift up into a gas layer, and when they hit the gas and you get another flash of light.

BBC: Dark Matter: Experiment to shed light on dark particles

The entire city of Fort Worth sits over a gas dense layer of black rock called the Barnett Shale that only recently became possible to access.

NPR: Drilling for Gas in Dallas-Fort Worth

This container is filled with 50kg of liquid argon and a thick layer of the element in its gas form.

BBC: Dark Matter: Experiment to shed light on dark particles

Dinosaur wind contained a high proportion of methane gas - powerful enough to damage the ozone layer, said the China Youth Daily quoting a French scientist.

BBC: Ill wind 'killed dinosaurs'

The problem was that (gas) was locked in shale, the extremely dense layer of rock under Dallas and Forth Worth.

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And that gas released into the atmosphere means faster erosion of the ozone layer, possibly speeding up the process and making matters even worse.

FORBES: Climate Catastrophe Nearer, Al Gore Gives Us About 90 More Years

Nitrous oxide is also considered a greenhouse gas and is 310 times more dangerous to the Earth's ozone layer than carbon dioxide, said Joseph Johns, chief of the U.S. attorney's environmental crimes section.

NPR: Feds Raid 17 Calif. Businesses For Nitrous Oxide

Packages covered with a sealed layer of clear plastic are modified-atmosphere packages, which have a gas-filled space inside to help preserve freshness and color.

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Methane is the principal component of natural gas, and massive amounts of it are trapped in reservoirs beneath the sea floor and under a layer of the ice-like substance.

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