NASA Spitzer Space Telescope Image: Dying Star Goes Out With a Ring
A new image from NASA’s Spitzer Space Telescope shows the shimmering
embers of a dying star, and in their midst a mysterious
doughnut-shaped ring.
“Spitzer’s infrared vision has revealed what could not be seen before
– a massive ring of material that was expelled from the dying star,”
said Dr. Joseph Hora, a Spitzer scientist at the Harvard-Smithsonian
Center for Astrophysics, Cambridge, Mass. “The composition of the ring
and how it formed are mysteries we hope to address with further
Spitzer studies.”
The new picture is available online at
http://photojournal.jpl.nasa.gov/catalog/PIA06755 .
The dying star is part of a “planetary nebula” called NGC 246. When a
star like our own Sun begins to run out of fuel, its core shrinks and
heats up, boiling off the star’s outer layers. Leftover material
shoots outward, expanding in shells around the star. This ejected
material is then bombarded with ultraviolet light from the central
star’s fiery surface, producing huge, glowing clouds – planetary
nebulas – that look like giant jellyfish in space.
These cosmic beauties last a relatively brief time, about a few
thousand years, in the approximately 10-billion-year lifetime of a
star. The name “planetary nebula” came from early astronomers who
thought the rounded clouds looked like planets.
NGC 246 is located 1,800 light-years away in the Cetus constellation
of our galaxy. Previous observations of this object by visible-light
telescopes showed a glistening orb of gas and dust surrounding a
central, compact star.
By cutting through the envelope of dust with its infrared eyes,
Spitzer provides a more transparent view through and behind the
nebula. “What we have seen with Spitzer is totally unexpected,” said
Hora. “Although previous observations showed the nebula had a patchy
appearance, Spitzer has revealed a ring component of this dying star,
possibly consisting of hydrogen molecules.”
In the new false-color picture, the ring appears clumpy and red and
off-center from the central star, while fluorescent, or ionized, gases
are green. The central star is the left white spot in the middle of
the cloud.
Ultimately, these data will help astronomers better understand how
planetary nebulas take shape, and how they nourish new generations of
stars. A scientific paper on this and other planetary nebulas observed
by Spitzer will be published on Sept. 1 in The Astrophysical Journal
Supplement, along with 75 other papers reporting Spitzer early mission
results.
Launched August 25, 2003, the Spitzer Space Telescope is the fourth of
NASA’s Great Observatories, a program that also includes the Hubble
Space Telescope, the Chandra X-ray Observatory and the Compton Gamma
Ray Observatory. Spitzer is also part of NASA’s Origins Program,
which seeks to answer the questions: Where did we come from? Are we
alone?
The Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer
Space Telescope mission for NASA’s Science Mission Directorate,
Washington, D.C. Science operations are conducted at the Spitzer
Science Center at the California Institute of Technology in Pasadena.
JPL is a division of Caltech. Spitzer’s infrared array camera, which
took the new picture of NGC 246, was built by NASA Goddard Space
Flight Center, Greenbelt, Md. The camera’s development was led by Dr.
Giovanni Fazio of Harvard-Smithsonian Center for Astrophysics.
Additional information about the Spitzer Space Telescope is available
at http://www.spitzer.caltech.edu .
