Name: Laurent Cassegrain Birth: around 1629 Birthplace: Chartres,France Today is the anniversary of the Birth of the French Catholic priest and instrument maker Laurent Cassegrain. Although this image may be a likeness of Laurent Cassegrain, no verifiable portrait of him is known to exist. he is best known to astronomers as being the probable inventor of a type of reflecting telescope which uses a combination of a primary concave mirror and a secondary convex mirror . Now known as the Cassegrain reflector, Cassegrain’s design first appeared in the 25 Apr 1672 issue (pictured) of Le Journal des Sçavans (established by French writer Denis de Sallo in 1665 and the earliest academic journal published in Europe). The 55 km diameter lunar crater Cassegrain, located to the south east of the larger crater Lebedev on the far side of the Moon and seen here immediately to the lower right of image centre, is named in his honour.
Name: Maria Mitchell Birthplace: Nantucket, Massachusetts Birthdate: 1 Aug 1818 Today is the anniversary of the American astronomer Maria Mitchell. The first woman to work as a professional astronomer in the USA, she became interested in the night sky at an early age after having been taught astronomy by her father. Maria gained fame when her prolonged search for a comet came to fruition when she observed a 6th magnitude comet on the evening of 1 Oct 1847 and was the first to report it. Although several other observers spotted the comet over the next few days, Maria Mitchell was credited with the original discovery. Comet 1847 VI (modern designation C/1847 T1) became known as ‘ Miss Mitchell’s Comet ’ and the discovery resulted in her being awarded a medal by King Frederick VI of Denmark who some years previously had established gold medal prizes to be awarded to the first discoverers of ‘telescopic comets’ (comets which were too faint to be seen with the nake...
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