Andrew Yee
August 4th 05, 09:23 PM
University of Colorado-Boulder
Office of News Services
Boulder, Colorado
Contact:
Larry Esposito, (303) 492-5990, (303) 492-7325
Jim Scott, (303) 492-3114
Aug. 4, 2005
New Cassini Images Show "Northern Lights" Of Saturn
New images of Saturn obtained by a University of Colorado at Boulder-led
team on June 21 using an instrument on the Cassini spacecraft show auroral
emissions at its poles similar to Earth's Northern Lights.
Taken with the Ultraviolet Imaging Spectrograph aboard the Cassini
orbiter, the two UV images, invisible to the human eye, are the first from
the Cassini-Huygens mission to capture the entire "oval" of the auroral
emissions at Saturn's south pole. They also show similar emissions at
Saturn's north pole, according to CU-Boulder Professor Larry Esposito,
principal investigator of the UVIS instrument built at CU-Boulder's
Laboratory for Atmospheric and Space Physics, and Professor Wayne Pryor of
Central Arizona College, a UVIS team member and former CU graduate
student.
In the false-color images, blue represents aurora emissions from hydrogen
gas excited by electron bombardment, while red-orange represents reflected
sunlight. The images show that the aurora lights at the polar regions
respond rapidly to changes in the solar wind, said the researchers.
Previous images have been taken closer to the equator, making it difficult
to see the polar regions.
Major changes in the emissions inside the Saturn south-pole aurora are
evident by comparing the two images, which were taken about one hour
apart, they said. The brightest spot in the left aurora fades, and a
bright spot appears in the middle of the aurora in the second image.
Made by slowly scanning the UVIS instrument across the planet, the images
also contain more than 2,000 wavelengths of spectral information within
each picture element. Researchers will use the wavelength information to
study Saturn's auroras, gases, and hazes and their changing distributions.
The UVIS observation team includes researchers from CU-Boulder, NASA's Jet
Propulsion Laboratory, Central Arizona College and the University of
Southern California.
The Cassini-Huygens mission is a cooperative project of NASA, the European
Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory,
a division of the California Institute of Technology in Pasadena, manages
the Cassini- Huygens mission for NASA's Space Science Mission Directorate
in Washington, D.C.
More information on the Cassini-Huygens mission is available at the
following Web sites:
http://saturn.jpl.nasa.gov
and
http://www.nasa.gov/cassini
Note to Editors: The new Saturn aurora image obtained by a CU-Boulder team
is available through the link in the caption to the right.
IMAGE CAPTION:
[http://www.colorado.edu/news/releases/2005/images/test10.jpg (112KB)]
New ultraviolet images from Cassini spacecraft show auroral emissions at
Saturn's poles.
Office of News Services
Boulder, Colorado
Contact:
Larry Esposito, (303) 492-5990, (303) 492-7325
Jim Scott, (303) 492-3114
Aug. 4, 2005
New Cassini Images Show "Northern Lights" Of Saturn
New images of Saturn obtained by a University of Colorado at Boulder-led
team on June 21 using an instrument on the Cassini spacecraft show auroral
emissions at its poles similar to Earth's Northern Lights.
Taken with the Ultraviolet Imaging Spectrograph aboard the Cassini
orbiter, the two UV images, invisible to the human eye, are the first from
the Cassini-Huygens mission to capture the entire "oval" of the auroral
emissions at Saturn's south pole. They also show similar emissions at
Saturn's north pole, according to CU-Boulder Professor Larry Esposito,
principal investigator of the UVIS instrument built at CU-Boulder's
Laboratory for Atmospheric and Space Physics, and Professor Wayne Pryor of
Central Arizona College, a UVIS team member and former CU graduate
student.
In the false-color images, blue represents aurora emissions from hydrogen
gas excited by electron bombardment, while red-orange represents reflected
sunlight. The images show that the aurora lights at the polar regions
respond rapidly to changes in the solar wind, said the researchers.
Previous images have been taken closer to the equator, making it difficult
to see the polar regions.
Major changes in the emissions inside the Saturn south-pole aurora are
evident by comparing the two images, which were taken about one hour
apart, they said. The brightest spot in the left aurora fades, and a
bright spot appears in the middle of the aurora in the second image.
Made by slowly scanning the UVIS instrument across the planet, the images
also contain more than 2,000 wavelengths of spectral information within
each picture element. Researchers will use the wavelength information to
study Saturn's auroras, gases, and hazes and their changing distributions.
The UVIS observation team includes researchers from CU-Boulder, NASA's Jet
Propulsion Laboratory, Central Arizona College and the University of
Southern California.
The Cassini-Huygens mission is a cooperative project of NASA, the European
Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory,
a division of the California Institute of Technology in Pasadena, manages
the Cassini- Huygens mission for NASA's Space Science Mission Directorate
in Washington, D.C.
More information on the Cassini-Huygens mission is available at the
following Web sites:
http://saturn.jpl.nasa.gov
and
http://www.nasa.gov/cassini
Note to Editors: The new Saturn aurora image obtained by a CU-Boulder team
is available through the link in the caption to the right.
IMAGE CAPTION:
[http://www.colorado.edu/news/releases/2005/images/test10.jpg (112KB)]
New ultraviolet images from Cassini spacecraft show auroral emissions at
Saturn's poles.