Week 30
This Week in History: July 19-25
JULY 19, 2009: An unknown object, most likely an asteroid a few hundred meters across, impacts Jupiter, leaving a black “scar” in Jupiter’s atmosphere that persists for the next one to two weeks; the “scar” was first noticed by amateur astronomer Anthony Wesley in New South Wales. The “scar” was reminiscent of those produced by …
Comet of the Week: Hale-Bopp C/1995 O1
Perihelion: 1997 April 1.14, q = 0.914 AU This week’s “Special Topics” presentation discusses, among other things, how the practice of discovering comets has changed over the years. Up until a couple of decades ago a rather large percentage of the known comets were discovered by amateur astronomers regularly scanning the skies with relatively small …
Special Topic: Discoveries and Surveys
Up until a few centuries ago, all the comets that were seen by human beings were “discovered” via the unaided eye. It is unlikely that there were ever any search efforts for these objects, rather, when they appeared they essentially revealed themselves to the people who were alive at that time. Probably the closest thing …