John (Jay) S. Gallagher III is an American

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, natural satellite, moons, comets and galaxy, g ...

and an expert on star formation in external galaxies, dwarf galaxies and dark matter. He is the William Morgan Professor of Astronomy at the University of Wisconsin-Madison where he has been a professor since 1991.

Background

He was raised near

New York City New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...

and received his undergraduate education at

Princeton University Princeton University is a private university, private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial Colleges, fourth-oldest ins ...

. He performed his graduate work at the

University of Wisconsin–Madison A university () is an educational institution, institution of higher education, higher (or Tertiary education, tertiary) education and research which awards academic degrees in several Discipline (academia), academic disciplines. Universities ty ...

, and was awarded a Ph.D in 1972. His supervisor was Arthur Code. After graduating he held positions at the

National Optical Astronomy Observatory The National Optical Astronomy Observatory (NOAO) was the United States national observatory for ground-based nighttime ultraviolet-optical-infrared (OUVIR) astronomy. The National Science Foundation (NSF) funded NOAO to provide forefront astronom ...

and at the

University of Illinois The University of Illinois Urbana-Champaign (U of I, Illinois, University of Illinois, or UIUC) is a public land-grant research university in Illinois in the twin cities of Champaign and Urbana. It is the flagship institution of the University ...

, and was the director of the

Lowell Observatory Lowell Observatory is an astronomical observatory in Flagstaff, Arizona, United States. Lowell Observatory was established in 1894, placing it among the oldest observatories in the United States, and was designated a National Historic Landmark ...

. He is currently a Professor of Astronomy at the

and last Editor of the

Astronomical Journal ''The Astronomical Journal'' (often abbreviated ''AJ'' in scientific papers and references) is a peer-reviewed monthly scientific journal owned by the American Astronomical Society (AAS) and currently published by IOP Publishing. It is one of the p ...

Scientific contributions

Some of Gallagher's major scientific contributions include a review article he wrote along with

Sandra Faber Sandra Moore Faber (born December 28, 1944) is an American astrophysicist known for her research on the evolution of galaxies. She is the University Professor of Astronomy and Astrophysics at the University of California, Santa Cruz, and works a ...

in 1979 that convinced most astronomers that dark matter was real. In the 1980s, with Deidre Hunter, he made the first substantial studies of

dwarf irregular galaxies An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a Spiral galaxy, spiral or an elliptical galaxy. Irregular galaxies do not fall into any of the regular classes of the Hubble sequence, and they are often chaotic ...

. He was later led research on some of the first methods for quantifying star formation in galaxies. Gallagher has made other major contributions towards our understanding of star formation in galaxies, the formation and evolution of low mass galaxies and stellar

nova A nova (plural novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", which is Latin for "new") that slowly fades over weeks or months. Causes of the dramati ...

. Gallagher was one of the leaders of the team which built the

Wide Field Planetary Camera 2 The Wide Field and Planetary Camera 2 (WFPC2) is a camera formerly installed on the Hubble Space Telescope. The camera was built by the Jet Propulsion Laboratory and is roughly the size of a baby grand piano. It was installed by servicing mission ...

for the Hubble Space Telescope.

References

{{DEFAULTSORT:Gallagher, John III American astronomers Science teachers University of Wisconsin–Madison alumni University of Wisconsin–Madison faculty University of Illinois faculty Princeton University alumni Living people 1947 births The Astronomical Journal editors