This week in history: Hale-Bopp discovered, Machu Picchu rediscovered, and Mozart finished symphony n.40. Read more below and dive deeper with The Great Courses Plus.
July 23, 1995 – Hale-Bopp Comet Discovered
On this day in 1995 a new comet would be separately observed by telescope by Alan Hale and Thomas Bopp. The comet, now known as the Hale-Bopp comet, was confirmed as a new comet the following morning. Its distance from the sun at the time of its original sighting was calculated to be somewhere between Jupiter and Saturn, marking it as the furthest distance a comet had been discovered by amateurs. The comet became visible to the naked eye in 1996 and would be at its brightest 1997 -so bright, in fact, that it could be observed within light polluted areas. It is still a visible cosmic entity if you look through a large telescope, though scientists believe that by 2020 it will be almost impossible to distinguish among distant galaxies.
Learn more about comets and other visible objects that orbit the earth in Skywatching: Seeing and Understanding Cosmic Wonders
July 24, 1911 – Machu Picchu Rediscovered
Nestled on a mountain peak a staggering 7,970 ft. above sea level, the ancient city of Machu Picchu is one of the spectacular sights of ancient Peru. Built by the Inca people some time in the 15th century, Machu Picchu is believed to have been a grand estate for the emperor Pachacuti. The citadel would be abandoned a century after its construction, roughly at the time of Spanish contact in Peru; some speculate that it was abandoned as the result of a smallpox outbreak brought on by the European arrivals. Because it was abandoned and so far out of sight, the Spanish never found and plundered Machu Picchu. It would be on this day in 1911 that American historian Hiram Bingham would come across the ancient city after hearing of spectacular ruins at the top of a mountain from some local men. Today, Machu Picchu is a UNESCO World Heritage Site and a Peruvian Historical Sanctuary.
Learn more about the Inca and Machu Picchu in The Lost Worlds of South America
July 25, 1788 – Mozart Completes Symphony no. 40 in G Minor
One of only two symphonies Wolfgang Amadeus Mozart wrote in the minor key, Symphony no. 40 would be completed on this day in 1788. He composed it at roughly the same time as Symphonies no. 39 and no. 41, leading to some speculation that they three pieces were meant to be parts of the same larger work. There are two versions of Symphony no. 40, with one version showcasing parts for a pair of clarinets that are absent in the other composition. Arguably one of Mozart’s most well-known compositions, Symphony no. 40 in G Minor is frequently performed by symphony orchestras into the modern era.