For the week including March 4, 2011

HEVELIUS’ LIZARD

After sundown, the fairly bright stars in the constellation of Cepheus, the King stand out in the northeast sky. Its central stars resemble a child’s drawing of a house. These stars of the King help to locate one of the fainter constellations of the region, Lacerta, the Lizard. This small constellation was the creation of the Polish astronomer, Johann Hevelius.

In 1611, when Galileo was using a new Dutch invention called a telescope to discover the moons of Jupiter and the rings of Saturn, Johann Hevelius was born in Danzig (now Gdansk), Poland. Having been introduced to astronomy as a teenager, Hevelius made major contributions to the science as an adult. In 1641, while performing several business and civic duties, he transformed his home into Stellaburgum, the finest observatory of the times. Using only the best observing equipment (most of which he constructed or designed himself), Hevelius began a study of the Moon. In 1647, he published the most accurate map of the lunar surface ever printed. (The presses that produced it were also part of his observatory.) This work alone would have insured Hevelius a place in history and modern astronomers still use his term maria to describe various dark features of the Moon. But as Hevelius’ explorations continued, so did his contributions. He discovered four comets and, while studying the historical accounts of hundreds of others, helped dispel the popular myth that comets were only strange weather phenomena occurring in the Earth’s atmosphere. Hevelius catalogued the positions of 1,564 stars and produced a beautifully detailed star atlas that rivaled the best efforts of the age. Astronomy has never been a very lucrative profession and astronomers of those days made their way as they could. Even Hevelius’ remarkable atlas was not spared a hard existence. The copper printing plates used to produce it were eventually hammered into teapot. History does not inform us as to whether the teapot was otherwise remarkable. On the whole though, Hevelius lived well. While astronomical giants like Johannes Kepler toiled in poverty, Hevelius’ business acumen served him well. He never tired of praising various royal or political figures, and made sure that they were immortalized among the stars of his atlas. The monetary contributions that flowed from these people enabled Hevelius to continue his research (and PR campaigns) in comfort.

If you’re up for a little sight seeing, try finding these features of that sky area on a clear night:

NGC 7635: If you have a moderately strong backyard telescope, look for the beautiful nebula called NGC 7635. Shown in the National Optical Astronomy Observatory photograph at upper right, NGC 7635 contains a region of expanding gases that has given it a nickname, “The Bubble Nebula”.

M39: A pair of binoculars is all you’ll need to find this bright cluster of stars. Shown in the photograph by Russel Croman at lower right, on very dark nights it can be glimpsed with naked eye.

Unless otherwise indicated, all content of this web site is the copyright of Robert Deegan and all rights are reserved.