Astronomer Biography

Danielle McCoy
Mr. Percival
Astronomy Honors
10 Oct. 2007
Johannes Hevelius

"The founder of lunar topography," Johannes Hevelius was born on the 28th of January 1611 in Danzig, Germany. In 1630, Hevelius studied jurisprudence at Leiden. Later, he traveled in England, France, and Switzerland. During his travels, he met many leading astronomers, including Pierre Gassendi. By 1634 he returned to and settled in his native town of Danzig. He worked as a brewer in the family business and later became town councillor. He married his first wife Katharina Rebeschke, who later died, and in 1663 he married Catherina Elisabetha Koopman, who could be considered one of the earliest recorded female astronomers.
By 1639, astronomy became his principle interest. In 1641, he built an observatory above his house, which included several excellent instruments. Included in his instruments was a tubeless telescope with 150 ft. focal length, which Hevelius constructed himself. His telescopes were described in detail in Machina coelestis, pars prior (1673), and was followed by Machina coelestis, para posterior (1679). On the 29th of January 1660, the King and Queen of Poland, John II and Maria Gonzaga, visited the observatory.

Hevelius dedicated many years of his life to making many observations of different aspects of astronomy. He spent 3 years making detailed observations of sunspots, devoted over 4 years of his life to charting the lunar surface, and discovered the moon’s libration in longitude. Many of his results were published in Selenographia (1647); due to this work, Johannes Hevelius is often called the founder of lunar topography. The work he did in Selenographia became known for its accurate illustrations of the lunar surface. Although, his system for naming the moon’s features did not last, but were replaced by Riccioli’s system (which used the names of famous astronomers and mathematicians). The only surviving term was mare (meaning sea), which is given to large dark plains. In the years 1652, 1661, 1672, and 1677, he discovered four comets and from this, suggested the theory of the revolution of these bodies in parabolic patterns around the sun. This idea was published in Cometographia in 1668. He also introduced the use of the vernier scale.

In a malicious fire on the 26th of September 1679, all of his instruments, books, and his observatory were destroyed. Though, he quickly repaired the damages, and was able to view the great comet of December 1680. His health deteriorated, and he later died from the shock of the fire on the 28th of January 1687, the day of his 76th birthday. After his death in 1687, his wife continued to publish many of his works.

Other works published by Hevelius include his 1690 publication of Prodromus Astronomiae, a catalogue of 1564 stars which contains Firmamentum sobiescianum, sive Uranographia, a famous collection of 50 excellent pictures of constellations. Hevelius gave names to eleven constellations, seven of which are still in use. He measured atmospheric refraction and compiled important observations of the planets, the penumbra of sunspots, and the bright regions of the Sun’s surface, for which he gave the name faculae, which is still used today.

Works Cited
"Johannes Hevelius." Adler Planetarium. 08 Oct. 2007 .
Van Helden, Al. "Johannes Hevelius." The Galileo Project. 1995. Rice University. 08 Oct. 2007 .