You can now buy the recently released book, Fall of a Thousand Suns: How Near Misses and Comet Impacts affected the Religious Beliefs of our Ancestors. It is available through iBooks and Amazon.
This website only lists information on modern-day comets and meteor showers. The book, however, thoroughly investigates how specific ancient impacts and near misses changed religious beliefs around the world.
The Discovery of the Eclipse Comet (C/1948 V1)
During a solar eclipse in 1948 a comet with an apparent magnitude of -2 was spotted near the Sun. Although, it wasn't the first comet ever spotted during an eclipse, it became infamously known as the "Eclipse Comet". It was officially designated C/1948 V1. As a side note, the first comet spotted during an eclipse may have been on April 30, 462 BCE when a Greek named Posidonius reported observing a comet during an eclipse.
C/1948 V1 was best observed in the southern hemisphere where the eclipse was total. Several comets have been spotted during an eclipse, including one in 471 CE recorded by Chinese and Byzantine astronomers, but the one in 1948 is perhaps the most famous.
After the Eclipse Comet passed perihelion, it was spotted rising in the morning before the Sun. C/1948 V1 now had a magnitude of 0. As it made its way back to the Oort Cloud, C/1948 V1 grew a tail spanning an estimated 30° of sky.
The Orbital Period of the Eclipse Comet (C/1948 V1)
C/1948 V1 has an orbital period thought by NASA to be roughly 84,600 years, which means this comet spends the vast majority of its life in the Oort Cloud.