Barbara A. Williams | |
---|---|
Alma mater | University of North Carolina at Greensboro University of Maryland, College Park |
Known for | Radio astronomy |
Scientific career | |
Institutions | University of Delaware University of North Carolina at Chapel Hill University of North Carolina at Greensboro |
Doctoral advisor | Frank John Kerr |
Barbara Ann Williams is an American radio astronomer who was the first African-American woman to earn a PhD in astronomy (University of Maryland, College Park, 1981). Her research largely focused on compact galaxy groups, in particular observations of their emissions in the H I region in order to build up a larger scale picture of the structure and evolution of galaxies. Williams was named as the Outstanding Young Woman of America in 1986. She is a retired associate professor in the Department of Physics and Astronomy at the University of Delaware.
Williams earned her bachelor's degree in physics at the University of North Carolina at Greensboro. [1] She moved to the University of Maryland, College Park for her graduate studies, earning a Master's and PhD in the field of radio astronomy in 1981. [2] [3] She was a member of Phi Beta Kappa academic honor society. Williams was the first African-American woman to earn a PhD in astronomy. [1] She studied elliptical galaxies using HI emissions. [4] She returned to the University of North Carolina at Greensboro as a research associate, where she worked until 1984. In 1984 Williams was appointed as a postdoctoral fellow at the University of North Carolina at Chapel Hill. She spent a year as a NASA-American Society for Engineering Education summer faculty member at the Goddard Space Flight Center. [5] She was named as the 1986 Outstanding Young Woman of America. [5]
Williams's research focused on radio astronomy and the study of galaxies. [6] [7] She used radio waves to examine groups of galaxies with compact cores [8] [9] [10] [11] and HI emissions to study several galaxies, including the IC 698 group. [12] [13] Williams's work on the Hickson Compact Group of galaxies established that atomic gases must undergo a phase transformation to result in the observed HI deficiency. [14] She used VLA neutral hydrogen imaging of compact galaxy groups. [15] [16]
Williams was made an associate professor at the University of Delaware in 1986. [1] There, Williams later studied educational research [17] and in particular strategies to retain women in physics. [18] Williams is a Fellow of the National Society of Black Physicists. [19]
Along with Sheella Mierson, Williams was the co-principal investigator of a study on problem-based learning in introductory sciences, in the Center for Teaching Effectiveness, University of Delaware. [20]
In the fields of Big Bang theory and cosmology, reionization is the process that caused electrically neutral atoms in the universe to reionize after the lapse of the "dark ages".
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Hercules A is a bright astronomical radio source in the constellation Hercules corresponding to the galaxy 3C 348.
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NGC 4388 is an active spiral galaxy in the equatorial constellation of Virgo. It was discovered April 17, 1784 by Wilhelm Herschel. This galaxy is located at a distance of 57 million light years and is receding with a radial velocity of 2,524km/s. It is one of the brightest galaxies of the Virgo Cluster due to its luminous nucleus. NGC 4388 is located 1.3° to the west of the cluster center, which translates to a projected distance of ≈400 kpc.
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NGC 4586 is a spiral galaxy located about 50 million light-years away in the constellation Virgo. The galaxy was discovered by astronomer William Herschel on February 2, 1786. Although listed in the Virgo Cluster Catalog, NGC 4586 is considered to be a member of the Virgo II Groups which form a southern extension of the Virgo cluster. NGC 4586 is currently in the process of infalling into the Virgo Cluster and is predicted to enter the cluster in about 500 million years.
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Barbara Sue Ryden is an American astrophysicist who is a Professor of Astronomy at Ohio State University. Her research considers the formation, shape and structure of galaxies. She was elected a fellow of the American Association for the Advancement of Science in 2016.
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