- Why is c the symbol for the speed of light? (math.ucr.edu)
Although c is now the universal symbol for the speed of light, the most common symbol in the nineteenth century was an upper-case V which Maxwell had started using in 1865. That was the notation adopted by Einstein for his first few papers on relativity from 1905. The origins of the letter c being used for the speed of light can be traced back to a paper of 1856 by Weber and Kohlrausch…
- Solar eclipse of August 21, 2017 (Wikipedia)
The solar eclipse of August 21, 2017, dubbed the “Great American Eclipse” by some media, was a total solar eclipse visible within a band that spanned the contiguous United States from the Pacific to the Atlantic coasts. It was also visible as a partial solar eclipse from as far north as Nunavut in northern Canada to as far south as northern South America. In northwestern Europe and Africa, it was partially visible in the late evening. In northeastern Asia, it was partially visible at sunrise.
Shadows from a solar eclipse