Pieter Dirkszoon Keyser
Encyclopedia
Pieter Dirkszoon Keyser a.k.a. Petrus Theodori, was a Dutch
navigator (originally from Emden
) who mapped the southern sky.
After several trips to Brazil
, Keyser participated as a first mate and the chief navigator of the first Dutch voyage to the East Indies
(the "Eerste Schipvaart"), which left Texel
with four ships on April 2, 1595. He had been specifically trained by Petrus Plancius
to map the southern stars. When the fleet finally was able to obtain fresh supplies at Madagascar
on September 13, 71 of the 248 sailors had died, most of scurvy
. The surviving crew stayed for several months on the island, to recover and make repairs, at which point Keyser probably made most of his celestial observations. He was aided in this by Frederick de Houtman
and Vechter Willemsz. After leaving Madagascar, it took another four months (Feb-Jun 1596) for the ships to reach Sumatra
and finally Bantam
on Java
. Trade negotiations went sour, perhaps caused by Portuguese
instigators, perhaps by inexperience, and the crew was forced to find drinking water and other supplies on Sumatra across the Sunda Strait
, at which crossing Keyser apparently died. On August 14, 1597, 81 survivors made it back to Texel, including de Houtman, who probably delivered Keyser's observations to Plancius.
From Keyser and de Houtman's observations Petrus Plancius
created twelve new constellations of the southern sky that have become accepted as modern constellations. The majority were named after various beings that 16th century explorers had encountered (e.g. Bird of Paradise, Chameleon, Toucan, Flying Fish). They were published on Plancius' celestial globe of late 1597, which was published by Jodocus Hondius
. Willem Janszoon Blaeu copied these constellations on a 1602 globe and created a new globe in 1603 based on Frederick de Houtman
's observations during a second voyage to the East Indies. Johann Bayer
copied the southern constellations from a Plancius/Hondius globe in his 1603 Uranometria
star atlas, crediting charting to a "Petrus Theodori", but not acknowledging their earlier publication, and is therefore often mistakenly credited for introducing them.
Keyser is commemorated by minor planet
(10655) Pietkeyser http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=10655.
Dutch Republic
The Dutch Republic — officially known as the Republic of the Seven United Netherlands , the Republic of the United Netherlands, or the Republic of the Seven United Provinces — was a republic in Europe existing from 1581 to 1795, preceding the Batavian Republic and ultimately...
navigator (originally from Emden
Emden
Emden is a city and seaport in the northwest of Germany, on the river Ems. It is the main city of the region of East Frisia; in 2006, the city had a total population of 51,692.-History:...
) who mapped the southern sky.
After several trips to Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
, Keyser participated as a first mate and the chief navigator of the first Dutch voyage to the East Indies
East Indies
East Indies is a term used by Europeans from the 16th century onwards to identify what is now known as Indian subcontinent or South Asia, Southeastern Asia, and the islands of Oceania, including the Malay Archipelago and the Philippines...
(the "Eerste Schipvaart"), which left Texel
Texel
Texel is a municipality and an island in the Netherlands, in the province of North Holland. It is the biggest and most populated of the Frisian Islands in the Wadden Sea, and also the westernmost of this archipelago, which extends to Denmark...
with four ships on April 2, 1595. He had been specifically trained by Petrus Plancius
Petrus Plancius
Petrus Plancius was a Dutch astronomer, cartographer and clergyman. He was born as Pieter Platevoet in Dranouter, now in Heuvelland, West Flanders. He studied theology in Germany and England...
to map the southern stars. When the fleet finally was able to obtain fresh supplies at Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
on September 13, 71 of the 248 sailors had died, most of scurvy
Scurvy
Scurvy is a disease resulting from a deficiency of vitamin C, which is required for the synthesis of collagen in humans. The chemical name for vitamin C, ascorbic acid, is derived from the Latin name of scurvy, scorbutus, which also provides the adjective scorbutic...
. The surviving crew stayed for several months on the island, to recover and make repairs, at which point Keyser probably made most of his celestial observations. He was aided in this by Frederick de Houtman
Frederick de Houtman
Frederick de Houtman , or Frederik de Houtman, was a Dutch explorer who sailed along the Western coast of Australia en route to Batavia.-Biography:...
and Vechter Willemsz. After leaving Madagascar, it took another four months (Feb-Jun 1596) for the ships to reach Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
and finally Bantam
Bantam (city)
Bantam in Banten province near the western end of Java was a strategically important site and formerly a major trading city, with a secure harbor on the Sunda Strait through which all ocean-going traffic passed, at the mouth of Banten River that provided a navigable passage for light craft into...
on Java
Java
Java is an island of Indonesia. With a population of 135 million , it is the world's most populous island, and one of the most densely populated regions in the world. It is home to 60% of Indonesia's population. The Indonesian capital city, Jakarta, is in west Java...
. Trade negotiations went sour, perhaps caused by Portuguese
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
instigators, perhaps by inexperience, and the crew was forced to find drinking water and other supplies on Sumatra across the Sunda Strait
Sunda Strait
The Sunda Strait is the strait between the Indonesian islands of Java and Sumatra. It connects the Java Sea to the Indian Ocean...
, at which crossing Keyser apparently died. On August 14, 1597, 81 survivors made it back to Texel, including de Houtman, who probably delivered Keyser's observations to Plancius.
From Keyser and de Houtman's observations Petrus Plancius
Petrus Plancius
Petrus Plancius was a Dutch astronomer, cartographer and clergyman. He was born as Pieter Platevoet in Dranouter, now in Heuvelland, West Flanders. He studied theology in Germany and England...
created twelve new constellations of the southern sky that have become accepted as modern constellations. The majority were named after various beings that 16th century explorers had encountered (e.g. Bird of Paradise, Chameleon, Toucan, Flying Fish). They were published on Plancius' celestial globe of late 1597, which was published by Jodocus Hondius
Jodocus Hondius
Jodocus Hondius , sometimes called Jodocus Hondius the Elder to distinguish him from his son Henricus Hondius II, was a Flemish artist, engraver, and cartographer...
. Willem Janszoon Blaeu copied these constellations on a 1602 globe and created a new globe in 1603 based on Frederick de Houtman
Frederick de Houtman
Frederick de Houtman , or Frederik de Houtman, was a Dutch explorer who sailed along the Western coast of Australia en route to Batavia.-Biography:...
's observations during a second voyage to the East Indies. Johann Bayer
Johann Bayer
Johann Bayer was a German lawyer and uranographer . He was born in Rain, Bavaria, in 1572. He began his study of philosophy in Ingolstadt in 1592, and moved later to Augsburg to begin work as a lawyer. He grew interested in astronomy during his time in Augsburg...
copied the southern constellations from a Plancius/Hondius globe in his 1603 Uranometria
Uranometria
Uranometria is the short title of a star atlas produced by Johann Bayer.It was published in Augsburg, Germany, in 1603 by Christophorus Mangus under the full title Uranometria : omnium asterismorum continens schemata, nova methodo delineata, aereis laminis expressa. This translates to...
star atlas, crediting charting to a "Petrus Theodori", but not acknowledging their earlier publication, and is therefore often mistakenly credited for introducing them.
Keyser is commemorated by minor planet
Minor planet
An asteroid group or minor-planet group is a population of minor planets that have a share broadly similar orbits. Members are generally unrelated to each other, unlike in an asteroid family, which often results from the break-up of a single asteroid...
(10655) Pietkeyser http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=10655.