It's the element whose atomic weight is closest to its atomic number
Using a kite antenna, he received the first transatlantic wireless message in 1901, the letter S
In 1977 the U.S. banned these that used freon as the propellant
Aircraft often use the "gyro" type of this instrument, as it's unaffected by local magnetic fields
Nearly all of the Earth's weather occurs in this layer of the atmosphere below the stratosphere
About 70% of this pungent gas produced is converted into fertilizer
Anthracite, the highest grade of coal, is composed almost entirely of this element
Scientists once tried to estimate the Earth's age by measuring the level of this substance in the ocean
Appropriately this sci-fi author called his 1984 collection of short stories "Pohlstars"
"The War With the Newts" is a satirical novel by this Czech dramatist who coined the word "robot"