The International Space Station. Credit: NASA
Showing posts with label CASSINI SPACECRAFT. Show all posts
Showing posts with label CASSINI SPACECRAFT. Show all posts

Sunday, January 26, 2014

NEW IMAGE OF SATURNS RINGS

FROM:  NASA 

Although it may look to our eyes like other images of the rings, this infrared image of Saturn's rings was taken with a special filter that will only admit light polarized in one direction. Scientists can use these images to learn more about the nature of the particles that make up Saturn's rings. The bright spot in the rings is the "opposition surge" where the Sun-Ring-Spacecraft angle passes through zero degrees. Ring scientists can also use the size and magnitude of this bright spot to learn more about the surface properties of the ring particles. This view looks toward the sunlit side of the rings from about 19 degrees above the ringplane. The image was taken with the Cassini spacecraft wide-angle camera on Aug. 18, 2013 using a spectral filter sensitive to wavelengths of near-infrared light centered at 705 nanometers. The view was acquired at a distance of approximately 712,000 miles (1.1 million kilometers) from Saturn and at a Sun-rings-spacecraft, or phase, angle of 7 degrees. Image scale is 43 miles (68 kilometers) per pixel.  Image Credit-NASA-JPL-Caltech-Space Science Institute.

Wednesday, January 16, 2013

TITAN'S LAKE DISTRICT AND CHANGES IN LAKE LEVELS


FROM: NASA
Titan's Lake District, One Season Later


These images obtained by NASA's Cassini spacecraft show Titan's stable northern lake district. Cassini's radar instrument obtained the recent images on May 22, 2012. It observed some previously unseen regions but also some regions containing lakes that were last observed about six years-nearly one Titan season--ago. This marks the longest time interval between lake observations in the northern hemisphere.

The top image here shows part of the radar swath from May 22, 2012, centered near 79 degrees north latitude, 58 degrees west longitude, and about 220 by 47 miles (350 by 75 kilometers) in dimension. At the bottom, parts of this image are compared with those obtained in 2006. (The images appear slightly different from previous releases because they use a new filtering technique). In 2006, it was winter in the northern hemisphere and the lakes were in the dark. Although Titan spring began in 2009 and the sun has now risen over the lakes, there is no apparent change in lake levels since the 2006 flybys, consistent with climate models that predict stability of liquid lakes over several years. This shows that the northern lakes are not transient weather events, in contrast to the temporary darkening of parts of the equator after a rainstorm in 2010 (PIA 12819).

Changes in lake levels may still be detected later in the mission as Cassini continues to observe these high northern latitudes into the beginning of summer in 2017. At that point, the sun may cause evaporation. However, the lack of significant change over six years sets important constraints for climate models and the stability of liquids on Titan. Illumination is coming from the bottom.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, DC. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. Image Credit: NASA/JPL-Caltech/ASI


Saturday, March 24, 2012

VIEW OF SATURN'S MOON ENCELADUS


The photo and following  excerpt is from the NASA website:
Below a darkened Enceladus, a plume of water ice is backlit in this view of one of Saturn's most dramatic moons. Dramatic plumes, both large and small, spray water ice from many locations along the moon's famed "tiger stripes" near the south pole of Enceladus. The tiger stripes are fissures that spray icy particles, water vapor and organic compounds. The terrain seen here is on the leading hemisphere of Enceladus (313 miles, or 504 kilometers across). North is up. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Feb. 20, 2012. The view was acquired at a distance of approximately 83,000 miles (134,000 kilometers) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 165 degrees. Image scale is 2,628 feet (801 meters) per pixel. Image credit: NASA/JPL-Caltech/Space Science Institute