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Week 15


APRIL 5, 1861: An amateur astronomer in New York, A.E. Thatcher, discovers a 9th-magnitude comet. Comet Thatcher was found to have an approximate orbital period of 415 years and is the parent comet of the Lyrid meteor shower, which peaks around April 22 each year. The Lyrids usually put on a modest display of less …

Perihelion: 2024 April 21.00, q = 0.781 AU  For this week’s “Comet of the Week” I am turning my eye towards the near-term future: a comet that I hope to see within the next few years.  While there perhaps is no exact formal definition of the term, the phrase “Halley-type comet” is generally used for …

A significant part of our knowledge about the “small bodies” of our solar system has come from the various spacecraft missions that have been to – or at least by – some of them. I’ll be covering these missions as a whole in a future “Special Topics” presentation, and where appropriate I am including results from …