Paul Kalas (born August 13, 1967) is a

Greek American Greek Americans ( el, Ελληνοαμερικανοί ''Ellinoamerikanoí'' ''Ellinoamerikánoi'' ) are Americans of full or partial Greek ancestry. The lowest estimate is that 1.2 million Americans are of Greek descent while the highest e ...

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...

known for his discoveries of

debris disk A debris disk (American English), or debris disc (Commonwealth English), is a circumstellar disk of dust and debris in orbit around a star. Sometimes these disks contain prominent rings, as seen in the image of Fomalhaut on the right. Debris di ...

s around stars. Kalas led a team of scientists to obtain the first visible-light images of an

extrasolar planet An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, init ...

with orbital motion around the star

Fomalhaut Fomalhaut is the brightest star in the southern constellation of Piscis Austrinus, the "Southern Fish", and one of the brightest stars in the night sky. It has the Bayer designation Alpha Piscis Austrini, which is Latinized from � ...

, at a distance of 25

light years A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

from

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

. The planet is referred to as Fomalhaut b.

Background

Kalas was born in

New York City New York, often called New York City or NYC, is the most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the most densely populated major city in the Un ...

to George Kavallinis and Maria Drettakis, who immigrated to the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

from

Heraklion Heraklion or Iraklion ( ; el, Ηράκλειο, , ) is the largest city and the administrative capital of the island of Crete and capital of Heraklion regional unit. It is the fourth largest city in Greece with a population of 211,370 (Urban Ar ...

Crete Crete ( el, Κρήτη, translit=, Modern: , Ancient: ) is the largest and most populous of the Greek islands, the 88th largest island in the world and the fifth largest island in the Mediterranean Sea, after Sicily, Sardinia, Cyprus, ...

. Kalas attended

Detroit Country Day School Detroit Country Day School (also known as DCD, DCDS, or Country Day) is a private, secular school located in four campuses in Oakland County, in the U.S. state of Michigan, north of Detroit. The administrative offices, facility services, safety a ...

Michigan Michigan () is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the List of U.S. states and ...

, and studied astronomy and physics at the

University of Michigan, Ann Arbor , mottoeng = "Arts, Knowledge, Truth" , former_names = Catholepistemiad, or University of Michigania (1817–1821) , budget = $10.3 billion (2021) , endowment = $17 billion (2021)As o ...

. He earned a

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

in Astronomy in 1996 from the

University of Hawaii A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States, th ...

under the direction of astronomer

David Jewitt David Clifford Jewitt (born 1958) is a British-American astronomer who studies the Solar System, especially its minor bodies. He is based at the University of California, Los Angeles, where he is a Member of the Institute for Geophysics and Pl ...

. Kalas worked as a postdoctoral scientist at the

Max Planck Institute for Astronomy The Max-Planck-Institut für Astronomie (Max Planck Institute for Astronomy, MPIA) is a research institute of the Max Planck Society (MPG). It is located in Heidelberg, Baden-Württemberg, Germany near the top of the Königstuhl, adjacent to the ...

in Heidelberg, Germany, the

Space Telescope Science Institute The Space Telescope Science Institute (STScI) is the science operations center for the Hubble Space Telescope (HST), science operations and mission operations center for the James Webb Space Telescope (JWST), and science operations center for the ...

, and the

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...

. In 2006, he became an Adjunct Professor of

Astronomy Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...

at the University of California, Berkeley. Kalas lives with his wife Aspasia Gkika and daughters Maria-Nikoleta and Natalia near

Berkeley, California Berkeley ( ) is a city on the eastern shore of San Francisco Bay in northern Alameda County, California, United States. It is named after the 18th-century Irish bishop and philosopher George Berkeley. It borders the cities of Oakland and E ...

Discoveries

Kalas discovered several circumstellar disks using a

coronagraph A coronagraph is a telescopic attachment designed to block out the direct light from a star so that nearby objects – which otherwise would be hidden in the star's bright glare – can be resolved. Most coronagraphs are intended to view t ...

on the

Hubble Space Telescope The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most vers ...

and at the University of Hawaii 2.2-meter telescope at Mauna Kea, Hawaii. In 1995 he discovered various forms of asymmetric structures in optical images of the Beta Pictoris disk. He was the lead scientist for the first optical images of debris disks surrounding the nearby red dwarf

AU Microscopii AU Microscopii (AU Mic) is a young small star located about away – about 8 times as far as the closest star after the Sun. The apparent visual magnitude of AU Microscopii is 8.73, which is too dim to be seen with the naked eye. It w ...

and the bright star

. Kalas'

image of

revealed a narrow belt of dusty material analogous to our

Solar System The Solar System Capitalization 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 "Solar ...

's Kuiper Belt. However, Kalas also found that Fomalhaut's belt is narrow and geometrically offset from the star by 15

astronomical units The astronomical unit (symbol: au, or or AU) is a unit of length, roughly the distance from Earth to the Sun and approximately equal to or 8.3 light-minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits ...

. These features are considered strong evidence for an

orbiting

that gravitationally sculpts the morphology of the belt.

Honors

* Elected

Fellow of the American Association for the Advancement of Science Fellowship of the American Association for the Advancement of Science (FAAAS) is an honor accorded by the American Association for the Advancement of Science (AAAS) to distinguished persons who are members of the Association. Fellows are elected ...

(2014) *

AIAA The American Institute of Aeronautics and Astronautics (AIAA) is a professional society for the field of aerospace engineering. The AIAA is the U.S. representative on the International Astronautical Federation and the International Council of t ...

William H. Pickering Lecture (2010) *

Newcomb Cleveland Prize The Newcomb Cleveland Prize of the American Association for the Advancement of Science (AAAS) is annually awarded to author(s) of outstanding scientific paper published in the Research Articles or Reports sections of ''Science''. Established in 192 ...

of the American Association for the Advancement of Science (2009)

Selected publications

Articles

* * *

Books

References

External links

The Circumstellar Disk Learning Site

Kalas' homepage

New Scientist article on HD 53143 and HD 139664 discoveries
{{DEFAULTSORT:Kalas, Paul American astronomers American people of Greek descent 1967 births Living people University of California, Berkeley faculty University of Michigan College of Literature, Science, and the Arts alumni University of Hawaiʻi alumni Detroit Country Day School alumni