with extragalactic planetary nebulae. Programs include measuring the
extragalactic distance scale and Hubble Constant, probing the kinematics
and dark matter content of elliptical galaxies, constraining the
the chemical and star formation history of Local Group objects,
examining the stellar populations of giant elliptical galaxies, and
discovering the structure and evolution of galaxy clusters through their
The Physics of Active Galactic Nuclei. Penn State astronomers are involved in both X-ray and optical studies of the supermassive black holes that reside in the nuclei of active galaxies.
Quasar Absorption Line analyses. Using quasars
as background flashlights, Penn State astronomers are probing the
kinematics, the chemical abundance patterns, and the detailed
structures of the interstellar media and intergalactic medium
throughout the Universe. Click on the image at left for a
description of the features seen in quasar spectra.
Galaxy Interactions and Galaxy Formation.
By studying the environments of compact
groups of galaxies and the tidal debris left over after collisions,
Penn State astronomers are deriving insights into the
mechanisms behind galaxy formation.
Searches for High Redshift Quasars.
Prof. Donald Schneider and his research
group are actively involved in searches for some of the most distant
and luminous objects in the Universe. Distant quasars are difficult
to locate; in addition to being faint and rare, they have the same
appearance as stars in photographs. Despite these complications,
it is possible to identify quasars because their spectra are very
different from those of stars. Schneider and his group are using the
Hobby-Eberly telescope extensively to search for high redshift
The Hubble Deep Field in X-rays. During the first year of CHANDRA operations, members of the Penn State/MIT ACIS team made an extremely deep X-ray image of the Hubble Deep Field (HDF) and the sky surrounding the HDF. These data are being used to resolve the X-ray background and examine the nature of the sources that contribute to the X-ray background (particularly above 2 KeV). The Hobby-Eberly Telescope and other telescopes will be used for rapid X-ray source identification.
Prof. Niel Brandt and
Prof. Donald Schneider have been
developing computer software that will allow X-ray source
detection/parameterization for the ACIS HDF observation.
1998 Annual Report
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