CICLOPS: Cassini Imaging Central Laboratory for OPerationS
Northern Aurora in Motion

Northern Aurora in Motion
PIA 11681

Avg Rating: 8.76/10

With Latitude Grid 480x345:
Flash 3.7 MB
Quicktime 9.5 MB
MP4 movie 3.1 MB


Northern Aurora in Motion
PIA 11681

Avg Rating: 8.74/10

Aurora Curtain Still Image 480x345:


Northern Aurora in Motion
PIA 11681

Avg Rating: 8.56/10

Snake-shaped Footprint Still 480x345:


Northern Aurora in Motion
PIA 11681

Avg Rating: 9.24/10

Without Latitude Grid 480x345:
Flash 3.7 MB
Quicktime 9.4 MB
MP4 movie 3.2 MB


Northern Aurora in Motion
PIA 11681

Avg Rating: 8.88/10

Aurora Curtain Still Image Without Grid 480x345:


Northern Aurora in Motion
PIA 11681

Avg Rating: 9.23/10

Snake-shaped Footprint Still Without Grid 480x345:
  An aurora, shining high above the northern part of Saturn, moves from the night side to the day side of the planet in this movie recorded by Cassini.

These observations, taken over four days, represent the first visible-light video of Saturn's auroras. They show tall auroral curtains, rapidly changing over time when viewed at the limb, or edge, of the planet's northern hemisphere. The sequence of images also reveals that Saturn's auroral curtains, the sheet-like formations of light-emitting atmospheric molecules, stretch up along Saturn's magnetic field and reach heights of more than 1,200 kilometers (750 miles) above the planet's limb. These are the tallest known "northern lights" in the solar system.

These auroral displays are created by charged particles from the magnetosphere that plunge into the planet's upper atmosphere and cause it to glow. The magnetosphere is the region of electrically charged particles that are trapped in the magnetic field of the planet. The auroral curtains shown in the movie reveal the paths that these charged particles take as they flow along lines of the magnetic field between the planet's magnetosphere and ionosphere.

The day side of Saturn scatters light toward Cassini, creating the overexposed triangle at the center of the left of the frame. Stars can be seen above the limb of the planet, trailing across the field of view.

The images were captured in black and white, but the aurora in this movie is shown in a false orange color to distinguish it from background noise in the images. The images were processed to remove cosmic ray hits, bad pixels and lens flare. On Earth, auroras often appear green, but scientists do not yet know the color of auroras on Saturn. Auroras on Saturn, like those on Earth, appear mostly in the high latitudes near the planet's poles. In the annotated version of the movie, latitude lines have been drawn on the planet at 70 and 78 degrees north latitude. The auroras can be seen moving with the planet's rotation along the curved path of about 74 degrees north latitude. They change shape and brightness in a manner similar to terrestrial auroras. The aurora curtains become particularly bright when they are projected edge-on to Cassini as they pass over the limb from the near (dark) side to the far (bright) side of Saturn. Near the end of the movie, a snake-shaped aurora footprint brightens abruptly and fades over about five frames.

The movie consists of 472 images taken during an 81-hour period. Each image was obtained with a two- or three-minute exposure.

These images were taken in visible light with the Cassini spacecraft's narrow-angle camera on Oct. 5 to 8, 2009. The view was acquired at a distance of approximately 2.8 million kilometers (1.7 million miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 111 degrees. Image scale is 32 kilometers (20 miles) per pixel.

The Cassini Equinox Mission is a joint United States and European endeavor. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini Equinox Mission visit, and

Credit: NASA/JPL/Space Science Institute
Released: November 24, 2009 (PIA 11681)
Image/Caption Information

Alliance Member Comments
cecalcali (Dec 4, 2009 at 7:48 PM):
Ce'CalCali message to Carolyn,the gallieo probe to jupiter was directed in to that planet at the end of its mission where are the close ups befor it sank into the planet question can cassini do the same by crashing into titan what could we learn if the process were repeated at titan or saturn (Nov 28, 2009 at 11:05 PM):
Another amazing capture of Nature's electromagnetic dance. Thank you, Carolyn Porco and your team. You keep topping your previous achievements. Robert Riccardi, M.D.
rochelimit (Nov 28, 2009 at 5:58 AM):
Very beautiful little video. Thanks for showing this.
dedhed (Nov 28, 2009 at 5:56 AM):
This is my first time to the website I'm 50 years old and have been around a few blocks in my day, and always look for new things to see, thank the team for alot more things I have never seen, AWSOME THANKS
Sergio (Nov 28, 2009 at 3:31 AM):
this is the second who have never seen Earth's aurora speaking.
This images and motion pictures are GREAT!
I logged in to ask which is the sequences timeframe length, but Peter wrote here that it is 81 hours and there are 472 images. Is this correct ?
If so, where can I get the whole images set ?
Thanks in advance.
Okieman46 (Nov 25, 2009 at 8:40 PM):
Thanks for the photos they are great. I grew up in Maine and do not recall actually seeing the Northern Lights there. I did however see a spooky red colored light show several years ago, while living here in southern Oklahoma. They are very spooky to say the least.
stowaway (Nov 25, 2009 at 1:35 PM):
...and I thought I was the only one who had never seen Earth's aurora
carolyn (CICLOPS) (Nov 25, 2009 at 9:13 AM):
PeterDarmady: Very happy to hear that. I've personally never seen the Earth's aurorae myself (save a really anemic display from Anchorage, Alaska a long time ago). Maybe someday I'll go to Scotland in the winter to catch a glimpse myself.
PeterDarmady (Nov 25, 2009 at 3:16 AM):
Shannon (my student, 13 yo) thinks that the Northern Lights on Saturn are AMAZING!!!!! She has never seen anything like it! 472 images in 81 hrs, subtracting an entire planet - cool! Up here in the North of Scotland, the aurorae are quite something and have been seen 50 degrees south of the zenith. Keep up the good work!
stowaway (Nov 24, 2009 at 11:18 PM):
There seems to be no end to the surprises coming from Saturn (and from the Imaging Team)