MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA 91109. TELEPHONE 818-354-5011
http://www.jpl.nasa.gov
Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov
Image advisory: 2010-386 Nov. 17, 2010
WISE Image Reveals Strange Specimen in Starry Sea
The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2010-386&cid=release_2010-386
PASADENA, Calif.-- A new image from NASA's Wide-field Infrared Survey Explorer shows
what looks like a glowing jellyfish floating at the bottom of a dark, speckled sea. In reality, this
critter belongs to the cosmos -- it's a dying star surrounded by fluorescing gas and two very
unusual rings.
"I am reminded of the jellyfish exhibition at the Monterey Bay Aquarium -- beautiful things
floating in water, except this one is in space," said Edward (Ned) Wright, the principal
investigator of the WISE mission at UCLA, and a co-author of a paper on the findings, reported
in the Astronomical Journal.
The object, known as NGC 1514 and sometimes the "Crystal Ball" nebula, belongs to a class of
objects called planetary nebulae, which form when dying stars toss off their outer layers of
material. Ultraviolet light from a central star, or in this case a pair of stars, causes the gas to
fluoresce with colorful light. The result is often beautiful -- these objects have been referred to as
the butterflies of space.
NGC 1514 was discovered in 1790 by Sir William Herschel, who noted that its "shining fluid"
meant that it could not be a faint cluster of stars, as originally suspected. Herschel had previously
coined the term planetary nebulae to describe similar objects with circular, planet-like shapes.
Planetary nebulae with asymmetrical wings of nebulosity are common. But nothing like the
newfound rings around NGC 1514 had been seen before. Astronomers say the rings are made of
dust ejected by the dying pair of stars at the center of NGC 1514. This burst of dust collided
with the walls of a cavity that was already cleared out by stellar winds, forming the rings.
"I just happened to look up one of my favorite objects in our WISE catalogue and was shocked
to see these odd rings," said Michael Ressler, a member of the WISE science team at NASA's Jet
Propulsion Laboratory in Pasadena, Calif., and lead author of the Astronomical Journal paper.
Ressler first became acquainted with the object years ago while playing around with his amateur
telescope on a desert camping trip. "It's funny how things come around full circle like this."
WISE was able to spot the rings for the first time because their dust is being heated and glows
with the infrared light that WISE can detect. In visible-light images, the rings are hidden from
view, overwhelmed by the brightly fluorescing clouds of gas.
"This object has been studied for more than 200 years, but WISE shows us it still has surprises,"
said Ressler.
Infrared light has been color-coded in the new WISE picture, such that blue represents light with
a wavelength of 3.4 microns; turquoise is 4.6-micron light; green is 12-micron light; and red is 22-
micron light. The dust rings stand out in orange. The greenish glow at the center is an inner shell
of material, blown out more recently than an outer shell that is too faint to be seen in WISE's
infrared view. The white dot in the middle is the central pair of stars, which are too close
together for WISE to see separately.
Ressler says NGC 1514's structure, though it looks unique, is probably similar in overall geometry
to other hour-glass nebulae, such as the Engraved Hourglass Nebula
(http://hubblesite.org/newscenter/archive/releases/1996/07). The structure looks different in
WISE's view because the rings are detectable only by their heat; they do not fluoresce at visible
wavelengths, as do the rings in the other objects.
Serendipitous findings like this one are common in survey missions like WISE, which comb
through the whole sky. WISE has been surveying the sky in infrared light since January 2010,
cataloguing hundreds of millions of asteroids, stars and galaxies. In late September, after
covering the sky about one-and-a-half times, it ran out of the frozen coolant needed to chill its
longest-wavelength detectors. The mission, now called NEOWISE, is still scanning the skies
with two of its infrared detectors, focusing primarily on comets and asteroids, including near-
Earth objects, which are bodies whose orbits pass relatively close to Earth's orbit around the sun.
The WISE science team says that more oddballs like NGC 1514 are sure to turn up in the
plethora of WISE data -- the first batch of which will be released to the astronomical community
in spring 2011.
Other study authors are Martin Cohen of the Monterey Institute for Research in Astronomy,
Marina, Calif.; Stefanie Wachter and Don Hoard of NASA's Spitzer Science Center at the
California Institute of Technology in Pasadena; and Amy Mainzer of JPL.
JPL manages and operates the Wide-field Infrared Survey Explorer for NASA's Science Mission
Directorate, Washington. The mission was competitively selected under NASA's Explorers
Program managed by the Goddard Space Flight Center, Greenbelt, Md. The science instrument
was built by the Space Dynamics Laboratory, Logan, Utah, and the spacecraft was built by Ball
Aerospace & Technologies Corp., Boulder, Colo. Science operations and data processing take
place at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for
NASA. More information is online at http://www.nasa.gov/wise , http://wise.astro.ucla.edu
and http://www.jpl.nasa.gov/wise .
-end-
To remove yourself from this mailing, please go to http://www.kintera.org/TR.asp?a=dnJJKTNtEaKGK1L&s=kuL2I7PNKgKOJ6OTIuF&m=ctIWKgNUJoK0JjK
To remove yourself from all mailings from NASA Jet Propulsion Laboratory, please go to http://www.kintera.org/TR.asp?a=gqLPK2OFKdJNIbK&s=kuL2I7PNKgKOJ6OTIuF&m=ctIWKgNUJoK0JjK
No comments:
Post a Comment