Johann Elert Bode

German astronomer

• Born: January 19, 1747; Hamburg, Germany
• Died: November 23, 1826; Berlin, Germany

Known as “the Berlin astronomer,” Johann Elert Bode popularized astronomy and stargazing in Germany in the late eighteenth century. His lavishly produced series of celestial maps capped the European tradition of depicting the constellations of the starry sky.

Primary field: Astronomy

Specialties: Observational astronomy; theoretical astronomy

Early Life

Johann Elert Bode was born on January 19, 1747, in the German city of Hamburg. His father, Johann Jakob Bode, ran a successful merchant school. His mother, Anna Margarethe Bode born Kruse, came from a bourgeois family. She gave birth to nine more children after Bode. Her brother, Jürgen Elert Kruse, became Bode’s godfather at his baptism on January 22. Kruse was Hamburg’s official arithmetician.

Bode contacted smallpox as a child, which made him blind in his right eye. He would continue to suffer from chronic infections of his left eye as well. A sickly boy, Bode spent most of his time at home, where he was schooled by his father.

In 1764, Bode entered his father’s merchant school, where he rose to prominence becoming his father’s assistant. At the same time, he pursued his awakening interest in mathematics, geography, and astronomy. He built basic telescopes out of old spectacles. Bode observed the starry sky from the rooftop of his parents’ house. He did this either in the early morning or late at night, before or after his work at his father’s school.

Bode proved particularly good at calculating celestial events such as eclipses and star occultations. In 1765, his work was discovered by Johann Georg Büsch, a teacher of mathematics at a Hamburg high school. Büsch let Bode use his own library and instruments. In 1766, at nineteen, Bode published his first work on the solar eclipse of August 5, 1766. He also began to write Anleitung zur Kenntniss des gestirnten Himmels auf jede einzelne Monate des Jahres eingerichtet (1768), in which he provided instructions for studying the sky, organized by month. The most popular astronomy book of the era, it was published in thirteen different editions.

On June 3, 1769, Bode observed the transition of Venus. He codiscovered a comet in the constellation of Taurus (C/1769 P1 Messier) on August 29, 1769. In July 1770, Bode observed another comet (P/Lexell).

Life’s Work

In 1772, Bode began studying the observations of fellow German astronomer Johann Daniel Titius. His finished work became known as the Titius-Bode Series, the Titius-Bode law, or Bode’s law. In the second edition of his book, Bode wrote of Titius’s mathematical formula that calculates the distance of the known planets from the sun. Although not initially credited, Titius was cited in subsequent editions.

In January 1772, mathematician Johann Heinrich Lambert suggested Bode’s name for a position at the Berlin Academy of Sciences. On July 1, Prussian king Frederick II appointed Bode as a royal astronomer and arithmetician at the academy. Bode flourished in Berlin. Together with Lambert, he launched the publication of the Berliner astronomisches Jahrbuch (Berlin astronomical almanac). For each year, the authors calculated the position of stars and planets for observation. After Lambert’s death in 1777, Bode became the sole author of the almanac, and it became a lifelong endeavor. Berliner astronomisches Jahrbuch continued to be printed until 1960.

On July 14, Bode married Johanna Christiane Lange, the great-niece of the Berlin astronomer Christine Kirch. On December 31, 1774, Bode discovered two galactic nebulae. They were M 81, which became known as Bode’s Galaxy, and the starburst galaxy M 82. On February 3, 1775, he discovered the globular cluster M 53. On May 8, Bode’s first daughter Christine was born.

In 1777, Bode created a catalogue of nebulae and star clusters for his astronomical almanac for 1779. He relied on the observations of other astronomers, which resulted in Bode’s inclusion of over twenty celestial objects that proved to be based on mistaken observations and did not exist. On December 27, Bode discovered the nebula M 92.

Bode followed up on the success of his popular astronomy book with Erläuterung der Sternkunde (1787). On January 6, 1779, he discovered a comet, called “Bode’s Comet” (C/1779 A1, 1779 Bode).

The discovery of a new planet by astronomer William Herschel on March 13, 1781, fascinated Bode. The planet was as far from the sun as the Titius-Bode Series had predicted. Bode was the first German astronomer to observe the new planet on August 1. He proved that the planet had been seen and recorded in 1690, yet misidentified as a star. As controversy raged about naming the new planet, Bode’s suggestion of Uranus on March 12, 1782, carried the day. In Greek mythology, Uranus was father of Saturn who fathered Jupiter, making for a persuasive mythological series for the solar system. Bode also published his first star atlas, Vorstellung der Gestirne, in 1782.

In November 1782, Bode’s wife died after giving birth to their fourth child, Karoline. In 1783, Bode married Sophie Dorothea Lange, his first wife’s older sister. Their first son, Ferdinand, was born on June 7, 1784. Around this time, Bode began to focus on theoretical and cartographic work.

On November 9, 1786, he became a full member of the Berlin Academy of Science. On May 10, 1787, he was appointed director of the Berlin Royal Observatory.

In 1789, Bode’s status as an eminent astronomer was confirmed when he was elected a fellow of the Royal Society of London. In September 1789, Queen Friederike Luise of Prussia visited the observatory.

In August 1790, Bode’s second wife died. He married Charlotte Wilhelmine Lehmann on February 23, 1791. In 1800, after reviewing a proposal sent by Bode, the Prussian king agreed to modernize the royal observatory. Astronomer Guiseppe Piazzi discovered the first dwarf planet, Ceres, on January 1, 1801, and the planet fit neatly into the position predicted by the Titius-Bode Series.

In 1801, Bode published the complete edition of his celestial atlas, Uranographia. It was considered a crowning achievement in the tradition of European sky atlases and featured elaborate pictures of the constellations.

By now, Bode was widely acclaimed as “the Berlin astronomer.” Even though he had to deal with some personal tragedies, such as the death of his oldest married daughter in 1814, Bode fulfilled his official duties with magnanimity. In 1819, upon orders of the king, the Prussian state bought the copper printing plates of the Uranographia, giving Bode some financial security.

In July 1822, Bode celebrated fifty years of service to Prussia. He was awarded with state medals. On December 19, his last wife died. In recognition of his contributions to astronomy, a crater on the moon was named after Bode on October 8, 1824. In 1825, Bode retired. He turned over the observatory, and finished his final astronomical almanac for 1829. After a pulmonary infection, he died on November 23, 1826. His personal effects, consisting primarily of his library, instruments, and globes, were sold at auction on March 26, 1867.

Impact

Bode contributed greatly to the popularization of astronomy and celestial observations in Germany at the end of the eighteenth century and beyond. His introduction to astronomy, the Anleitung zur Kenntniss des gestirnten Himmels,became a classic among German speakers interested in astronomy.

Bode’s Astronomisches Jahrbuch became well known among both professional and amateur German astronomers. This almanac survived until 1960, when it merged with two other international scientific almanacs. In its era, Bode’s Uranographia was considered one of the most beautiful atlases of the sky; it is now seen as one of the best examples of the European celestial cartographic tradition.

After Bode popularized it in 1772, the Titius-Bode Series, or Bode’s law, fascinated fellow astronomers. Its validity seemed prove after it accurately predicted the discovery of Uranus in 1781, and Ceres in 1801. However, the subsequent discovery of Pallas (1802), Juno (1804), and Vesta (1807) near Ceres led to their correct reclassification as asteroids or dwarf planets, casting doubt on Bode’s law. The discovery of Neptune in 1846, outside the range predicted by the Titius-Bode Series, laid the foundation for the contemporary professional consensus that the “law” is a mere coincidence.

Bode’s astronomical discoveries consist of two galaxies, two star clusters, and two comets. Yet his primary impact was as a scientist who sparked broad interest in astronomy in Germany and the rest of Europe.

Bibliography

Baum, Richard. The Haunted Observatory: Curiosities from the Astronomer’s Cabinet. Amherst, New York: Prometheus, 2007. Print. Baum comments on the effect of the Titius-Bode law on the search for a possible planet between Mars and Jupiter. Includes letters written to Bode, from individuals claiming to see new objects in the sky.

Boss, Alan. “Is It a Coincidence that Most Planets Fall Within the Titius-Bode Law’s Boundaries?” Astronomy Magazine 30.10 (Oct. 2006): 70. Print. Argues that Bode’s law is a mathematical coincidence.

Hoskin, Michael. “The Discovery of Uranus, the Titius-Bode Law, and the Asteroids.” The General History of Astronomy: Planetary Astronomy from the Renaissance to the Rise of Astrophysics. Eds. Rene Taton and Curtis Wilson. New York: Cambridge UP, 2009. 169–80. Print. Reviews the quest to discover a missing planet between Mars and Jupiter as predicted by Bode’s law.

Kanas, Nick. Star Maps: History, Artistry, and Cartography. Chichester: Praxis, 2009. Print. Provides a detailed account of Bode’s star maps, including his major achievement, the Uranographia, also placing Bode and his work in the context of astronomical map-making in his time. Illustrated.