I was a bit worried about driving up to the observatory today, but it turned out to be a short and not-too-steep drive. Construction on this observatory began in 1925 and still continues, although a lot of their telescopes are used for educational purposes, instead of for discovery. The biggest is the Clark telescope, housed here.
The Pluto telescope is called that because it is the one used to discover the planet Pluto. Do you remember reading about how the researchers used a special machine that flipped negatives of the photos taken over several weeks period? The researchers had to look for the one spot of light that “moved” indicating it was a planet and not a star. They demonstrated the equipment, except that they had already marked the negatives with an arrow showing the planet as it jumped from one place to another. Cheating!! The truth is, however, that we would never have noticed that tiny dot of light move without the arrows showing us where it was.