A Half-Enceladus
This half-lit view of Enceladus bears a passing resemblance to similar views of Earth's own natural satellite, but the similarities end there. Earth's rocky moon is covered in dark, volcanic basins and brighter, mountainous highlands -- both exceedingly ancient. The surface of icy Enceladus is uniformly bright, far brighter than Earth's moon. Large areas of Enceladus' surface are characterized by youthful (on geologic timescales), wrinkled terrains.
Although the north pole of Enceladus (313 miles or 504 kilometers across) was dark when Cassini arrived at Saturn, the march of the seasons at Saturn have brought sunlight to the north and taken it from the south.
This view looks toward the leading hemisphere of Enceladus. North on Encealdus is up. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 8, 2015.
The view was acquired at a distance of approximately 80,000 miles (129,000 kilometers) from Enceladus. Image scale is 2,530 feet (772 meters) per pixel.
The Cassini mission is a cooperative project of NASA, ESA (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. 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, Colorado.
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 at http://ciclops.org .
Credit: NASA/JPL-Caltech/Space Science Institute
Last Updated: Jan. 25, 2016
Editor: Tony Greicius
Janus and Tethys
Janus and Tethys demonstrate the main difference between small moons and large ones. It's all about the moon's shape.
Moons like Tethys (660 miles or 1,062 kilometers across) are large enough that their own gravity is sufficient to overcome the material strength of the substances they are made of (mostly ice in the case of Tethys) and mold them into spherical shapes. But small moons like Janus (111 miles or 179 kilometers across) are not massive enough for their gravity to form them into a sphere. Janus and its like are left as irregularly shaped bodies.
Saturn's narrow F ring and the outer edge of its A ring slice across the scene.
This view looks toward the unilluminated side of the rings from about 0.23 degrees below the ring plane. The image was taken in visible green light with the Cassini spacecraft narrow-angle camera on Oct. 27, 2015.
The view was obtained at a distance of approximately 593,000 miles (955,000 kilometers) from Janus. Image scale at Janus is 3.7 miles (6 kilometers) per pixel. Tethys was at a distance of 810,000 miles (1.3 million kilometers) for an image scale of 5 miles (8 kilometers) per pixel.
The Cassini mission is a cooperative project of NASA, ESA (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. 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, Colorado.
For more information about the Cassini-Huygens mission visit http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.
Credit: NASA/JPL-Caltech/Space Science Institute
Last Updated: Jan. 19, 2016
Editor: Tony Greicius
el dispensador dice:
el gigante de los cien brazos aguarda,
su fase asoma,
mientras la hoguera pasa...
las evidencias hablan,
mientras las existencias estampan,
la humanidad en sus apuros...
anda atrapada,
sin ver las señales,
que "alguien" les manda...
el espacio es mucho más que vacío,
cuando la ecuación es negada.
ENERO 25, 2016.-
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