Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/~gibson/pleiades/press/press_release.txt Дата изменения: Wed Jan 24 21:57:50 1996 Дата индексирования: Sat Dec 22 17:19:51 2007 Кодировка: Поисковые слова: arp 220

FOR RELEASE: 9:20 AM CST January 16, 1996


ZOOMING IN ON THE PLEIADES REFLECTION NEBULA

The secret lives of nebulae -- vast shining clouds of interstellar dust and gas
that are among the most spectacular objects in the night sky -- are being
revealed by a multi-instrument survey of the Pleiades Reflection Nebula.

Using observations from optical, radio, ultraviolet and infrared telescopes,
Steven Gibson of the University of Wisconsin-Madison is building a
multiwavelength mosaic of the Pleiades that promises an exquisitely-detailed
look at the structure of the famous nebula.

The goal of the work, said Gibson, is to understand the dynamics and fine
structure of the wispy filaments that make up the nebula and how the dust
grains in the nebula reflect starlight. By studying how starlight is absorbed
and reflected by dust in the nebula, astronomers can gain a better
understanding of both the physical nature of the dust grains and their location
with respect to the stars.

The latter will also help scientists construct a three-dimensional map of the
nebula and should answer some questions about how it is interacting with the
Pleiades cluster. Already Gibson and collaborators Kenneth Nordsieck of
UW-Madison and Mark Holdaway of the National Radio Astronomy Observatory have
added substantial evidence to the theory that the dust and gas the Pleiades
nebula is composed of does not come from the famous cluster of stars that gives
the nebula its name.

Instead, says Gibson, it appears that the material may have originated hundreds
of light years away from the star cluster -- known as the Pleiades or Seven
Sisters -- that lights up the famous nebula.


PICTURE CAPTIONS:

Intricately structured filaments of gas and dust compose the reflection nebula
seen around the Pleiades star cluster. These multiwavelength images were
presented to the American Astronomical Society meeting in San Antonio, TX on
January 16, 1996.

(blue image): Faint reflection nebulosity -- starlight shining off grains of
interstellar dust -- extends far from the `Seven Sisters' in the center of the
cluster. This mosaic of 40 visible-light images was taken with the 0.6-meter
(24-inch) Burrell Schmidt telescope at Kitt Peak National Observatory, near
Tucson, Arizona.

(green image): Numerous wisps and streamers of atomic Hydrogen gas are found
near the Pleiades and appear to be closely associated with dust filaments seen
at optical and infrared wavelengths. This composite image of large-scale and
fine-scale structure was made from 21-cm wavelength radio telescope
observations, using the Green Bank 140-ft. telescope in West Virginia and the
Very Large Array telescope in New Mexico.

(red image): Glowing filaments seen in the far-infrared are the result of dust
particles, heated by the Pleiades stars, re-radiating their energy into space.
This image is from data taken by the Infra-Red Astronomical Satellite (IRAS) in
the 1980s.

PHOTO CREDITS:

Authors:
Steven Gibson, University of Wisconsin-Madison
Mark Holdaway, National Radio Astronomy Observatory
Kenneth Nordsieck, University of Wisconsin-Madison

Facilities:
National Radio Astronomy Observatory (NRAO)
National Optical Astronomy Observatories (NOAO)
The Warner and Swasey Observatory of Case Western Reserve University
Infrared Processing and Analysis Center (IPAC)
SkyView astronomical imaging engine on the World Wide Web

Funding Sources:
NASA grant NAG5-647 (WISP project)
NOAO (observing/reduction support)
NRAO (observing/reduction support)