Paula Cleggett-Haleim
Headquarters, Washington, D.C.                             January 13, 1992
(Phone:  202/453-1547)                                     12:30 P.M. EST

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
(Phone:  410/338-4514)

Dr. Doug Duncan
Space Telescope Science Institute, Baltimore, Md.
(Phone:  410/338-4935)


RELEASE:  92-5

HST PROBES THE CHEMISTRY OF THE EARLY UNIVERSE


	Using a unique capability of NASA's Hubble Space Telescope (HST),
astronomers announced today that they have detected the rare element
boron in an ancient star.  This element may be "fossil" evidence of
energetic events which accompanied the birth of the Milky Way galaxy.  An
alternative possibility is that this rare element may be even older, dating
from the birth of our universe.  If so, then the HST findings may force
some modification in theories of the Big Bang itself.

	Dr. Douglas Duncan, of the Space Telescope Science Institute in
Baltimore, Md., and Drs. David Lambert and Michael Lemke, of the
University of Texas, Austin, announced their results today to a press
conference at the 179th meeting of the American Astronomical Society in
Atlanta.  The research will be presented to the meeting of the society in a
session for late papers on Thursday, Jan. 16.

	The light from boron only appears in the ultraviolet part of the
spectrum and so does not penetrate Earth's atmosphere.  "That's why no
one was able to make this discovery before,'' says Dr. Duncan.  "Having a
powerful telescope high above Earth's absorbing atmosphere has given
scientists a new window on the universe.  This was always considered to be
one of the most important reasons for building the Space Telescope."

	Using HST's Goddard High Resolution Spectrograph, the researchers
detected traces of boron in a yellow 7th magnitude star called HD 140283,
located 100 light-years away in the constellation Libra.  At an estimated age
of 15 billion years, the star is one of the oldest known.

	Because it was among the first stars to form in the Milky Way galaxy,
HD 140283 should contain elements which were incorporated into the
star long ago.  Preserved in the star for billions of years, such material
offers clues to conditions of the early universe when the star formed.

	Predictably, HD 140283 contains mostly primordial elements
synthesized in the Big Bang, such as hydrogen, helium and traces of
lithium.  Heavier elements such as carbon, nitrogen, oxygen and others
found in the Sun, the Earth and Solar System planets are thought to have
been built up during the lifetime of the galaxy by nuclear reactions in
successive generations of stars.

	The discovery of boron comes as a surprise, however.  Previously,
another rare element, beryllium, had been detected in the star with
ground-based telescopes.

	The key question is from where did the beryllium and boron come.
Scientists know that today, beryllium and boron are produced by cosmic
rays, high-speed and extremely energetic particles which occasionally
collide with atoms in interstellar space and split them apart into lighter
elements.  If substantial amounts of beryllium and boron, the fourth and
fifth lightest elements, were formed very rapidly early in the history of the
Milky Way, swarms of energetic particles may have been present at the
birth of the galaxy.  The cosmic rays could have been produced by
supernovas or other highly energetic events which occurred early in the
life of the Milky Way.

	However, the astronomers found slightly different relative
proportions of beryllium and boron than what is expected from cosmic ray
production.  This offers the alternative possibility that beryllium and boron
were synthesized in the first moments of the universe's creation.

	The currently accepted version of the Big Bang says that the early
universe was uniformly hot and dense.  However, more recent theories
suggest that the Big Bang developed some structure even during the first
few minutes.  These new theories differ from the traditional one in
predicting that small but detectable amounts of beryllium and boron might
be created.

	To confirm these results, the astronomers plan additional HST
observations of an even older star later this year.  If the boron was
produced by cosmic rays within the young Milky Way, it should diminish
the farther back in time the astronomers look, hence closer to the birth of
the galaxy.  If, instead, astronomers find the same amount of boron in the
older star, rather than less, the finding will support the alternative
explanation that boron was produced in the Big Bang.

	"Either way, this will be an exciting test to show which of the
possible explanations is correct," concludes Duncan.  "We know that our
picture of the beginning of the galaxy and the beginning of the universe is
undoubtedly oversimplified, and it is satisfying to be able to add a little
more detail."