Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.arcetri.astro.it/~palla/ANDREAIMMAGINI/ISM/JetDisk3.txt Дата изменения: Wed Jan 24 20:09:39 2001 Дата индексирования: Sat Dec 22 08:11:14 2007 Кодировка: Поисковые слова: supernova

EMBARGOED UNTIL: 2:00 P.M. (EDT)
JUNE 6, 1995

PHOTO RELEASE NO.: STSCI-PRC95-24a


HUBBLE VIEWS OF THREE STELLAR JETS

These NASA Hubble Space Telescope views of gaseous jets from
three newly forming stars show a new level of detail in the star
formation process, and are helping to solve decade-old questions
about the secrets of star birth. Jets are a common "exhaust product"
of the dynamics of star formation. They are blasted away from a disk
of gas and dust falling onto an embryonic star.

[upper left] - This view of a protostellar object called HH-30 reveals an
edge-on disk of dust encircling a newly forming star. Light from the
forming star illuminates the top and bottom surfaces of the disk,
making them visible, while the star itself is hidden behind the
densest parts of the disk. The reddish jet emanates from the
inner region of the disk, and possibly directly from the star itself.
Hubble's detailed view shows, for the first time, that the jet expands
for several billion miles from the star, but then stays confined to a
narrow beam. The protostar is 450 light-years away in the
constellation Taurus.

Credit: C. Burrows (STScI & ESA), the WFPC 2 Investigation
Definition Team, and NASA

[upper right] - This view of a different and more distant jet in object
HH-34 shows a remarkable beaded structure. Once thought to be a
hydrodynamic effect (similar to shock diamonds in a jet aircraft
exhaust), this structure is actually produced by a machine-gun-like
blast of "bullets" of dense gas ejected from the star at speeds of
one-half million miles per hour. This structure suggests the star goes
through episodic "fits" of construction where chunks of material fall
onto the star from a surrounding disk. The protostar is 1,500 light-
years away and in the vicinity of the Orion Nebula, a nearby star
birth region.

Credit: J. Hester (Arizona State University), the WFPC 2 Investigation
Definition Team, and NASA

[bottom] - This view of a three trillion mile-long jet called HH-47 reveals
a very complicated jet pattern that indicates the star (hidden inside a
dust cloud near the left edge of the image) might be wobbling, possibly
caused by the gravitational pull of a companion star. Hubble's detailed
view shows that the jet has burrowed a cavity through the dense gas
cloud and now travels at high speed into interstellar space. Shock
waves form when the jet collides with interstellar gas, causing the jet
to glow. The white filaments on the left reflect light from the obscured
newborn star. The HH-47 system is 1,500 light-years away, and lies at
the edge of the Gum Nebula, possibly an ancient supernova remnant
which can be seen from Earth's southern hemisphere.

Credit: J. Morse/STScI, and NASA

The scale in the bottom left corner of each picture represents 93 billion miles,
or 1,000 times the distance between Earth and the Sun. All images were taken
with the Wide Field Planetary Camera 2 in visible light. The HH designation
stands for "Herbig-Haro" object -- the name for bright patches of nebulosity
which appear to be moving away from associated protostars.