Tethys appears to be peeking out from behind Rhea, watching the watcher.
Scientists believe that Tethys’ surprisingly high albedo is due to the water ice jets emerging from its neighbor, Enceladus. The fresh water ice becomes the E ring and can eventually arrive at Tethys, giving it a fresh surface layer of clean ice.
Lit terrain seen here is on the anti-Saturn side of Rhea. North on Rhea is up. The image was taken in red light with the Cassini spacecraft narrow-angle camera on April 20, 2012.
The view was obtained at a distance of approximately 1.1 million miles (1.8 million kilometers) from Rhea and at a Sun-Rhea-spacecraft, or phase, angle of 59 degrees. Image scale is 7 miles (11 kilometers) per pixel.
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 mission for NASA’s Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov or http://www.nasa.gov/cassini. The Cassini imaging team homepage is athttp://ciclops.org .
Credit: NASA/JPL-Caltech/Space Science Institute
The Elephant’s Trunk nebula is a concentration of interstellar gas and dust within the much larger ionized gas region IC 1396 located in the constellation Cepheus about 2,400 light years away from Earth. The piece of the nebula shown here is the dark, dense globule IC 1396A; it is commonly called the Elephant’s Trunk nebula because of its appearance at visible light wavelengths, where there is a dark patch with a bright, sinuous rim. The bright rim is the surface of the dense cloud that is being illuminated and ionized by a very bright, massive star (HD 206267) that is just to the west of IC 1396A. (In the Figure above, the massive star is just to the left of the edge of the image.) The entire IC 1396 region is ionized by the massive star, except for dense globules that can protect themselves from the star’s harsh ultraviolet rays.
Imaging telescopes or lenses: Sky-Watcher Equinox 120/900 ED APO
Imaging cameras: QHY CCD ALCCD 8L
Mounts: Skywatcher NEQ 6 PRO
Guiding telescopes or lenses: Lacerta Off-Axis-Guider (extra short) T2 Guide-Cam connector
Guiding cameras: Lacerta M-Gen MGEN II
Focal reducers: Skywatcher .85x Focal Reducer & Corrector
Software: MSB AstroArt 5, Adobe Photoshop CC 14
Filters: Baader Planetarium HA 36mm 7nm Filter, Baader Planetarium OIII 36mm 8,5nm Filter, Baader Planetarium SII 36mm 8nm Filter
Accessories: Filterschublade T2-T2 36mm, LACERTA MGEN Autoguider, V 2.12
Dates: Dec. 15, 2014
Frames: 20×600″ -15C bin 1×1
Integration: 3.3 hours
Flat darks: ~20
Avg. Moon age: 22.56 days
Avg. Moon phase: 45.62%
Bortle Dark-Sky Scale: 4.00
RA center: 323.532 degrees
DEC center: 57.609 degrees
Pixel scale: 2.513 arcsec/pixel
Orientation: -86.739 degrees
Field radius: 0.945 degrees
Locations: NEUSTADT, HANNOVER, GERMANY, NEUSTADT AM RÜBENBERGE, NIEDERSACHSEN, Germany