Aleksander Wolszczan (born 29 April 1946) is a Polish

astronomer An astronomer is a scientist in the field of astronomy who focuses on a specific question or field outside the scope of Earth. Astronomers observe astronomical objects, such as stars, planets, natural satellite, moons, comets and galaxy, galax ...

. He is the co-discoverer of the first confirmed extrasolar planets and pulsar planets. He is a graduate of the

Nicolaus Copernicus University in Toruń Nicolaus Copernicus University in Toruń or NCU (, UMK) is located in Toruń, Poland. It is named after Nicolaus Copernicus, who was born in Toruń in 1473. History The beginnings of higher education in Toruń The first institution of higher ...

and works as a professor at the

Pennsylvania State University The Pennsylvania State University (Penn State or PSU) is a Public university, public Commonwealth System of Higher Education, state-related Land-grant university, land-grant research university with campuses and facilities throughout Pennsyl ...

. Wolszczan is a fellow of the

Polish Academy of Sciences The Polish Academy of Sciences (, PAN) is a Polish state-sponsored institution of higher learning. Headquartered in Warsaw, it is responsible for spearheading the development of science across the country by a society of distinguished scholars a ...

, the

American Astronomical Society The American Astronomical Society (AAS, sometimes spoken as "double-A-S") is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC. The primary objective of the AAS is to promote the adv ...

and the

International Astronomical Union The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...

. He is also the recipient of numerous awards for his groundbreaking contributions in the field of astronomy including Prize of the Foundation for Polish Science, Beatrice M. Tinsley Prize and the Marian Smoluchowski Medal of the Polish Physical Society.

Early life and education

Wolszczan was born on 29 April 1946 in Szczecinek located in present-day

West Pomeranian Voivodeship West Pomeranian Voivodeship is a Voivodeships of Poland, voivodeship (province) in northwestern Poland. Its capital and largest city is Szczecin. Its area equals , and in 2021, it was inhabited by 1,682,003 people. It was established on 1 Janua ...

, Poland; in the 1950s his family moved to

Szczecin Szczecin ( , , ; ; ; or ) is the capital city, capital and largest city of the West Pomeranian Voivodeship in northwestern Poland. Located near the Baltic Sea and the Poland-Germany border, German border, it is a major port, seaport, the la ...

. His father Jerzy Wolszczan taught economics at former Szczecin Polytechnic (currently West Pomeranian University of Technology) and his mother, Zofia, worked for the Polish Writers' Union. His early interest in

astronomy Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest includ ...

was inspired by his father who told him stories and myths connected with stellar

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

s. As a seven-year-old he already learned the basics of astronomy. He observed the night sky using a small telescope he constructed himself. He graduated from Stefan Czarniecki VI High School in Szczecin.

Scientific career

Wolszczan sat for an M.Sc. in 1969 and a Ph.D. in 1975 at the

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It extends from the Baltic Sea in the north to the Sudetes and Carpathian Mountains in the south, bordered by Lithuania and Russia to the northeast, Belarus and Ukrai ...

. Between 1969 and 1973 he worked at the Department of Radioastronomy of the Institute of Astronomy. In 1973, as a senior assistant, he moved to

Bonn Bonn () is a federal city in the German state of North Rhine-Westphalia, located on the banks of the Rhine. With a population exceeding 300,000, it lies about south-southeast of Cologne, in the southernmost part of the Rhine-Ruhr region. This ...

for training at the Max Planck Institute for Radio Astronomy. From 1979 to 1982 he worked at the Astronomical Center of the Polish Academy of Sciences in

Toruń Toruń is a city on the Vistula River in north-central Poland and a World Heritage Sites of Poland, UNESCO World Heritage Site. Its population was 196,935 as of December 2021. Previously, it was the capital of the Toruń Voivodeship (1975–199 ...

, and in 1982 he moved to the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

to work at

Cornell University Cornell University is a Private university, private Ivy League research university based in Ithaca, New York, United States. The university was co-founded by American philanthropist Ezra Cornell and historian and educator Andrew Dickson W ...

and Princeton. Later he became an astronomy professor at

. From 1994 to 2008, he was also professor at the Nicolaus Copernicus University. He is a member of the

. Working with Dale Frail, Wolszczan carried out astronomical observations from the

Arecibo Observatory The Arecibo Observatory, also known as the National Astronomy and Ionosphere Center (NAIC) and formerly known as the Arecibo Ionosphere Observatory, is an observatory in Barrio Esperanza, Arecibo, Puerto Rico owned by the US National Science F ...

Puerto Rico ; abbreviated PR), officially the Commonwealth of Puerto Rico, is a Government of Puerto Rico, self-governing Caribbean Geography of Puerto Rico, archipelago and island organized as an Territories of the United States, unincorporated territo ...

that led them to the discovery of the

pulsar A pulsar (''pulsating star, on the model of quasar'') is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation out of its Poles of astronomical bodies#Magnetic poles, magnetic poles. This radiation can be obse ...

PSR B1257+12 in 1990. On 9 January 1992 they discovered that the pulsar was orbited by two planets, whose masses were initially assessed at 3.4 and 2.8 times Earth's mass. The radii of their orbits are 0.36 and 0.47 AU respectively. This was the first confirmed discovery of planets outside the

Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...

(as of 2 June 2021, 4,401 such planets were known). Wolszczan announced his findings in 1992 during the Meeting of the

Atlanta Atlanta ( ) is the List of capitals in the United States, capital and List of municipalities in Georgia (U.S. state), most populous city in the U.S. state of Georgia (U.S. state), Georgia. It is the county seat, seat of Fulton County, Georg ...

. Two years later he published the results of his discovery and was chosen by the journal ''

Nature Nature is an inherent character or constitution, particularly of the Ecosphere (planetary), ecosphere or the universe as a whole. In this general sense nature refers to the Scientific law, laws, elements and phenomenon, phenomena of the physic ...

'' as the author of one of 15 fundamental discoveries in the field of physics. Despite some initial misgivings by several experts, today his discovery is regarded as fully substantiated. Astronomer Bohdan Paczyński called it "the greatest discovery by a Polish astronomer since Copernicus." In 1998, ''

Astronomy Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest includ ...

'' magazine included his discovery among The 25 Greatest Astronomical Findings of All Time. At the Arecibo Observatory, Wolszczan also collaborated with Joseph H. Taylor Jr and conducted research on millisecond pulsars. In 2003 Maciej Konacki and Wolszczan determined the orbital inclinations of the two pulsar planets, showing that the actual masses were approximately 3.9 and 4.3 Earth masses respectively. In 2007, Wolszczan was also part of a Polish team of astronomers led by Andrzej Niedzielski that found yet another planet outside the Solar System, HD 17092 b, orbiting star HD 17092. In 2012, Matthew Route and Wolszczan detected bursts of radio waves emitted from 2MASS J10475385+2124234 using

. This T6.5 brown dwarf has a temperature of 800-900 K, making it the coolest known radio-emitting substellar object. Its magnetic field is stronger than 1.7 kG. In 2016, the team discovered the most rapidly rotating brown dwarf, the T6 WISEPC J112254.73+255021.5. Its rotation period may be as little as 17 minutes. In 2017, he was awarded the Bohdan Paczyński Medal conferred by the Polish Astronomical Society. Wolszczan is a member of many scientific associations which include: the

, American Association for the Advancement of Sciences, International Union of Radio Science,

, and Polish Institute of Arts and Sciences of America.

Recognition

At Pennsylvania State University, Wolszczan held the Evan Pugh Professorship of Astronomy and Astrophysics. Upon retirement in 2024, he was awarded the title of Atherton Professor. In 1992 Wolszczan won the Prize of the Foundation for Polish Science. In 1996, he was awarded the Beatrice M. Tinsley Prize by the

, and in 1997 Polish President Aleksander Kwaśniewski presented him with the Commander's Cross of the

Order of Polonia Restituta The Order of Polonia Restituta (, ) is a Polish state decoration, state Order (decoration), order established 4 February 1921. It is conferred on both military and civilians as well as on alien (law), foreigners for outstanding achievements in ...

for outstanding contributions to Polish science. In 2002, he appeared on a Polish postage stamp (as part of a series of 16 stamps, titled "Polish Millennium," which summarizes the last 1,000 years of history, culture, and science in

). In 2006, Wolszczan officially became an honorary citizen of

. In 2007, Jan Sosiński directed a

documentary A documentary film (often described simply as a documentary) is a nonfiction Film, motion picture intended to "document reality, primarily for instruction, education or maintaining a Recorded history, historical record". The American author and ...

film on the life and scientific work of Wolszczan entitled ''Gwiazdor - Aleksander Wolszczan''. He was elected a Legacy Fellow of the

in 2020.

Controversy

In 2008 '' Gazeta Prawna'' disclosed that from 1973 until 1981 Wolszczan was an

informant An informant (also called an informer or, as a slang term, a "snitch", "rat", "canary", "stool pigeon", "stoolie", "tout" or "grass", among other terms) is a person who provides privileged information, or (usually damaging) information inten ...

(codenamed "Lange") for the Polish communist-era Służba Bezpieczeństwa. He confirmed this, but stressed that he was passing only unimportant information, usually publicly known, and that he did not harm anybody. The resulting controversy in Polish media resulted in his resignation from

Notes

References

Wolszczan, A., and D.A. Frail. ''A planetary system around the millisecond pulsar PSR 1257+12.'' Nature 355(6356):145-7, January 9, 1992.
* Wolszczan, A. ''Confirmation of Earth-mass planets orbiting the millisecond pulsar PSR B1257+12.'' Science 264(5158):538-42, 22 April 1994.
Konacki, M. and Wolszczan, A. ''Masses and Orbital Inclinations of Planets in the PSR B1257+12 System'' Astrophysical Journal, Volume 591, Issue 2, pp. L147-L150, 2003.

External links

{{DEFAULTSORT:Wolszczan, Aleksander 1946 births Living people People from Szczecinek 20th-century Polish astronomers Radio astronomers Nicolaus Copernicus University in Toruń alumni Pennsylvania State University faculty Cornell University faculty Winners of the Beatrice M. Tinsley Prize Discoverers of exoplanets Members of the Polish Academy of Sciences Recipients of the Order of Polonia Restituta 21st-century Polish astronomers Fellows of the American Astronomical Society