Scientists
Vera Rubin
American astronomer who established the presence of dark matter in galaxies, measures spectra in the 1970s.
She uncovered the discrepancy between the
predicted angular motion of galaxies and the observed motion, by studying
galactic rotation
curves. This phenomenon became known
as the galaxy rotation problem.
Vera Rubin continues
to explore the galaxies. In 1992, she discovered a galaxy (NGC 4550) in which
half the stars in the disk are orbiting in one direction and half in the
opposite direction, with both systems intermingled! Perhaps this resulted from
the merging of two galaxies rotating in opposite directions. Rubin has since
found several other cases of similarly bizarre behavior. More recently, she and
her colleagues found that half the galaxies in the great Virgo cluster show
signs of disturbances due to close gravitational encounters with other
galaxies.
In recognition of
her achievements, Vera Rubin was elected to the National Academy of Sciences
and in 1993 was awarded the National Medal of Science.
Cecilia Payne - Gaposchkin
British
- American astronomer and astrophysicist who in 1925, proposed in her PhD
thesis an explanation for the composition of stars in terms of the relative abundances of
hydrogen and helium.
Payne also contributed widely to the physical understanding
of variable stars. Much of this work was done in association with the Russian
astronomer Sergei Gaposchkin, whom she married in 1934.
From the time she finished her
Ph.D. through the 1930s, Payne advised students, conducted research, and
lectured—all the usual duties of a professor. Yet, because she was a woman, her
only title at Harvard was “technical assistant” to Professor Shapley. Despite
being indisputably one of the most brilliant and creative astronomers of the
twentieth century, Cecilia Payne was never elected to the elite National
Academy of Sciences. But times were beginning to change. In 1956, she was
finally made a full professor (the first woman so recognized at Harvard) and
chair of the Astronomy Department.
Her fellow astronomers certainly
came to appreciate her genius. In 1976, the American Astronomical Society
awarded her the prestigious Henry Norris Russell Prize.
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