Astronomy
A Formula For SETI
1960 AD GREEN BANK, WEST VIRGINIA Frank Drake, the man who conducted the first modern search for radio signals from other civilizations, developed a way of thinking about how many civilizations there could be in our galaxy. It’s now known as the Drake Equation: N = R x Fs x Fp x Ne x Fl [...]
Comets: Beyond the Atmosphere
1572 AD HVEN ISLAND, DENMARK Just how far away are comets? The Greek philosopher Aristotle said they were disturbances in the atmosphere, but the great Danish astronomer Tycho (pronounced "TY-koh") Brahe proved him wrong. Copernicus had recently begun the revolution that would let us understand the universe, by showing that the Earth was not the [...]