My first Magazine Sky & Telescope - 01.2019

by Gabriella Bernardi 400 Thalers or 50 Pounds C aroline Herschel is probably the most famo ous female astronomer of the early modern era a. In 1772, her celebrated brother William, discoverer of Uranus, brought her to England, wh here she helped him in his activities, ﬁrst as a singer a nd then as an astronomer. Although this little woma an (a disease in her youth limited her growth to abo ut 4 feet 3 inches) had to work under the supervi- sion of her renowned brother, she was gradually able to pursue an independent astronomical care er sprinkled with several important successes. She discovered 14 deep-sky objects, including galaxies s and open clusters that William later included in his catalog, as well as eight comets; the ﬁrst of these comets, discovered on the night of August 1, 178 6, is now designated C/1786 P1 Herschel. In the Herschel era, the discovery of a comet w was reputed to be so important that it led to another historical milestone. In the year following Caro- line’s ﬁ rst comet discovery, King George III recog- - nized her astronomical work (as an assistant to h her A brother) and assigned her a salary of 50 pounds per p year. This made Caroline Herschel the ﬁrst salarie ed woman astronomer, at least in modern history. Almost 50 years later, near the end of her life, she e and Mary Somerville became the ﬁrst female mem m- bers of the Royal Astronomical Society. Given the enormous difﬁculties that women faced at the time, Herschel built an impressive career, and her importance should not be under- estimated, even if it turns out that she was not the ﬁ rst professional woman astronomer. Actuall y, primacy should be awarded to another European astronomer. In 1787 Caroline Herschel became th he ﬁ rst woman in the United Kingdom to be paid as an astronomer, but the second in the world. The honor of ﬁ rst had already been earned by a German observer named Christine Kirch. The Family Tree Anecdotal evidence tells us that in her child- hood, Christine used to mark the time, or time intervals, with a pendulum. From Galileo onward ds, the pendulum had been used in Europe for time- 68 JA N UA RY 2 019 • SK Y & TELESCOPE C B Who was the ﬁ rst professional woman astronomer? keeping. A stronomers usually used a seconds ulum, which had a period of two seconds pendu ne second per swing). While tracking (on the pendulum’s motion was probably a E game for Christine, it was actually a help to her family. She was the ﬁrst daughter of two astronomers, and at the age of 10 she, together with her brother and sister, was instructed in the family business. Christine’s mother, Maria Mar- garethe Winkelmann, gave birth to her in 1696 in Guben, Germany. D Christine had been preceded by a brother, Christfried, in 1694, and would be followed by a sister, Marga- w reth a, in 1703. (There were seven children in the fa amily, but we only have information ne, Christfried, and Margaretha.) Their about Christin father, Gottfri ed Kirch, was one of the most famous nomers of the 18th century. He was German astron famous for the e ﬁrst discovery of a comet made with a telescope, in 1680, and for the detection of the Chi (χ) Cygni, one of three variable variability of C stars known at t the time. And with Winkelmann’s the Observatory of the Royal assistance, he managed m Prussian Acade emy of Sciences in Berlin. ne belonged to a notable yet somewhat So, Christin peculiar family y. Her mother was born in Panitzsch, Saxony, in 167 0 to a Lutheran pastor who believed in equal educa tion for both sexes and who made a UM GAME Little is known about the exact tim- t THE PENDULU ing mechanism us sed in the Kirch household, but the clock was probably a secon ds pendulum with an escapement anchor, like ere (E). A thread and nut on the bottom of the the one shown he pendulum bob all owed the user to adjust the rate of the clock. d passed through a fork (A) and transferred its The pendulum rod er rod (B), which turned on a horizontal axis motion to an uppe (C). The curved es scapement anchor was attached to the axis, ndulum was in motion, the teeth of the escape- and when the pen onnected with the anchor’s limbs. This press of ment wheel (D) co was transmitted to the pendulum to reduce the tooth-on-anchor w angle of its motio n, which meant that it required less energy to swing. The Kirch children made a game of counting pendulum ack of time while observing. swings to keep tra PHYSICS PAYMENT POSTPONED

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