Photograph

//image: //movie: http://www.nasa.gov/mov/410700main_pia11682.mov This movie from Cassini, made possible only as Saturn’s north pole emerged from winter darkness, shows new details of a jet stream that follows a hexagon-shaped path and has long puzzled scientists. The hexagon was hidden in darkness during the winter of Saturn’s long year, a year that is equal to about 29 Earth years. But as the planet approached its August 2009 equinox and signaled the start of northern spring, the hexagon was revealed to Cassini’s cameras. This is the first time the whole hexagonal shape has been mapped out in visible light by Cassini, and these images show unprecedented details of Saturn’s high northern latitudes. The hexagon was originally discovered in images taken by Voyager spacecraft in the early 1980s. Since 2006, the Cassini Visual and Infrared Mapping Spectrometer (VIMS) instrument has been observing the hexagon at infrared wavelengths, but at lower spatial resolution than these visible light images. Three large mosaics were used to create this three-frame movie. The mosaics used dozens of images and the constituent images were projected into polar projections to provide a complete view of the hexagon. The mosaics used in this movie do not show the region directly around the north pole because it had not yet fully emerged from the polar winter night. Seams between the images are visible in the third frame of the movie because the observation geometry in those images made removal of the seams difficult. The six-sided shape remains a mystery. Scientists think the hexagon is a meandering jet stream at 77 degrees north latitude, but they don’t know what controls the path the stream takes. These images also show new phenomena for scientists to decipher, such as waves that can now be seen radiating from the corners of the hexagon where the jet takes its hardest turns. These images confirm the presence of a multi-walled structure in each of the hexagon’s six sides, and the structure now can be seen extending to the top of Saturn’s cloud layer. The images show that the inside of the hexagon is darker than the outside. The new images also show a large spot inside the hexagon that could be related to a dark spot seen inside the hexagon in 2006 in an image taken by Cassini’s VIMS instrument. An earlier Voyager mosaic showed a large spot outside the hexagon. That spot existed at least until 1991 before disappearing into the long winter polar night. Images from Voyager and from ground-based telescopes suffered from poor viewing perspectives. In late 2006, Cassini’s VIMS camera imaged the region in the thermal infrared wavelength, showing the hexagon in false color. Multiple images acquired by the VIMS instrument over a 12-day period showed that the feature is nearly stationary and is likely an unusually strong pole-encircling planetary wave that extends deep into the atmosphere. Scientists had speculated that a large vortex seen outside the hexagon during the Voyager observations exerted forces on the jet stream making it adopt a hexagonal pattern in a manner similar to how jet streams on Earth divert around high-pressure systems. However, in these new images, the vortex is notably absent while the hexagon persists almost 30 years after it was first seen. The images were taken in visible light with the Cassini spacecraft wide-angle camera on Jan. 3, 2009. The images were obtained at a distance of approximately 764,000 kilometers (475,000 miles) from Saturn. The smallest resolved features at the latitude of the hexagon have a horizontal scale of approximately 100 kilometers. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the mission for the Science Mission Directorate at NASA Headquarters in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org. Image credit: NASA/JPL/Space Science Institute

//image:

//movie:

http://www.nasa.gov/mov/410700main_pia11682.mov

This movie from Cassini, made possible only as Saturn’s north pole emerged from winter darkness, shows new details of a jet stream that follows a hexagon-shaped path and has long puzzled scientists.

The hexagon was hidden in darkness during the winter of Saturn’s long year, a year that is equal to about 29 Earth years. But as the planet approached its August 2009 equinox and signaled the start of northern spring, the hexagon was revealed to Cassini’s cameras. This is the first time the whole hexagonal shape has been mapped out in visible light by Cassini, and these images show unprecedented details of Saturn’s high northern latitudes. The hexagon was originally discovered in images taken by Voyager spacecraft in the early 1980s. Since 2006, the Cassini Visual and Infrared Mapping Spectrometer (VIMS) instrument has been observing the hexagon at infrared wavelengths, but at lower spatial resolution than these visible light images.

Three large mosaics were used to create this three-frame movie. The mosaics used dozens of images and the constituent images were projected into polar projections to provide a complete view of the hexagon. The mosaics used in this movie do not show the region directly around the north pole because it had not yet fully emerged from the polar winter night. Seams between the images are visible in the third frame of the movie because the observation geometry in those images made removal of the seams difficult.

The six-sided shape remains a mystery. Scientists think the hexagon is a meandering jet stream at 77 degrees north latitude, but they don’t know what controls the path the stream takes. These images also show new phenomena for scientists to decipher, such as waves that can now be seen radiating from the corners of the hexagon where the jet takes its hardest turns. These images confirm the presence of a multi-walled structure in each of the hexagon’s six sides, and the structure now can be seen extending to the top of Saturn’s cloud layer. The images show that the inside of the hexagon is darker than the outside. The new images also show a large spot inside the hexagon that could be related to a dark spot seen inside the hexagon in 2006 in an image taken by Cassini’s VIMS instrument. An earlier Voyager mosaic showed a large spot outside the hexagon. That spot existed at least until 1991 before disappearing into the long winter polar night.

Images from Voyager and from ground-based telescopes suffered from poor viewing perspectives. In late 2006, Cassini’s VIMS camera imaged the region in the thermal infrared wavelength, showing the hexagon in false color. Multiple images acquired by the VIMS instrument over a 12-day period showed that the feature is nearly stationary and is likely an unusually strong pole-encircling planetary wave that extends deep into the atmosphere. Scientists had speculated that a large vortex seen outside the hexagon during the Voyager observations exerted forces on the jet stream making it adopt a hexagonal pattern in a manner similar to how jet streams on Earth divert around high-pressure systems. However, in these new images, the vortex is notably absent while the hexagon persists almost 30 years after it was first seen.

The images were taken in visible light with the Cassini spacecraft wide-angle camera on Jan. 3, 2009. The images were obtained at a distance of approximately 764,000 kilometers (475,000 miles) from Saturn. The smallest resolved features at the latitude of the hexagon have a horizontal scale of approximately 100 kilometers.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the mission for the Science Mission Directorate at NASA Headquarters in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Image credit: NASA/JPL/Space Science Institute



December 17, 2009, 1:00pm

Photograph

The Dark Side of Carbon As interest in Earth’s changing climate heats up, a tiny dark particle is stepping into the limelight: black carbon. Commonly known as soot, black carbon enters the air when fossil fuels and biofuels, such as coal, wood, and diesel are burned. Black carbon is found worldwide, but its presence and impact are particularly strong in Asia.Black carbon, a short-lived particle, is in perpetual motion across the globe. The Tibetan Plateau’s high levels of black carbon likely impact the region’s temperature, clouds and monsoon season.Image Credit: NASA

The Dark Side of Carbon

As interest in Earth’s changing climate heats up, a tiny dark particle is stepping into the limelight: black carbon. Commonly known as soot, black carbon enters the air when fossil fuels and biofuels, such as coal, wood, and diesel are burned. Black carbon is found worldwide, but its presence and impact are particularly strong in Asia.

Black carbon, a short-lived particle, is in perpetual motion across the globe. The Tibetan Plateau’s high levels of black carbon likely impact the region’s temperature, clouds and monsoon season.

Image Credit: NASA



December 16, 2009, 3:03pm

Photograph

Image: Approaching Marquette Island NASA’s Mars Exploration Rover Opportunity took this picture of a rock informally named ‘Marquette Island’ as it approached the rock for investigations that have suggested the rock is a stony meteorite.Opportunity used its navigation camera to record this image during the 2,056th Martian day, or sol, of the rover’s mission on Mars (Nov. 5, 2009).The dark-toned rock stood out so prominently in more distant views on earlier sols that the rover team referred to it as ‘Sore Thumb’ before assigning the Marquette name in accord with an informal naming convention of choosing island names for the isolated rocks that the rover is finding as it crosses a relatively barren plain on its long trek from Victoria Crater toward Endeavour Crater. Image Credit: NASA/JPL-Caltech

Image:

Approaching Marquette Island

NASA’s Mars Exploration Rover Opportunity took this picture of a rock informally named ‘Marquette Island’ as it approached the rock for investigations that have suggested the rock is a stony meteorite.

Opportunity used its navigation camera to record this image during the 2,056th Martian day, or sol, of the rover’s mission on Mars (Nov. 5, 2009).

The dark-toned rock stood out so prominently in more distant views on earlier sols that the rover team referred to it as ‘Sore Thumb’ before assigning the Marquette name in accord with an informal naming convention of choosing island names for the isolated rocks that the rover is finding as it crosses a relatively barren plain on its long trek from Victoria Crater toward Endeavour Crater. 

Image Credit: NASA/JPL-Caltech



December 15, 2009, 2:05pm

Photograph

Image: Global Digital Elevation Model This Global Digital Elevation Model, or GDEM, is a product of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), a joint program of NASA and Japan’s Ministry of Economy, Trade and Industry. The image was released on June 29, 2009, and was created by processing and stereo-correlating the 1.3 million-scene ASTER archive of optical images, covering Earth’s land surface between 83 degrees North and 83 degrees South latitudes. The GDEM is produced with 98-feet postings, and is formatted as 23,000 one-by-one-degree tiles. In this colorized version, low elevations are purple, medium elevations are greens and yellows, and high elevations are orange, red and white.With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 50 to 300 feet, ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on NASA’s Terra satellite. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change. Image Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

Image:

Global Digital Elevation Model

This Global Digital Elevation Model, or GDEM, is a product of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), a joint program of NASA and Japan’s Ministry of Economy, Trade and Industry. The image was released on June 29, 2009, and was created by processing and stereo-correlating the 1.3 million-scene ASTER archive of optical images, covering Earth’s land surface between 83 degrees North and 83 degrees South latitudes. The GDEM is produced with 98-feet postings, and is formatted as 23,000 one-by-one-degree tiles. In this colorized version, low elevations are purple, medium elevations are greens and yellows, and high elevations are orange, red and white.

With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 50 to 300 feet, ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on NASA’s Terra satellite. 

The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change. 

Image Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team



December 15, 2009, 2:04pm

Photograph

During its mission, the Galileo spacecraft returned a number of images of Earth’s only natural satellite. Galileo surveyed the moon on Dec. 7, 1992, on its way to explore the Jupiter system in 1995-1997. This color mosaic was assembled from 18 images taken by Galileo’s imaging system through a green filter. On the upperleft is the dark, lava-filled Mare Imbrium, Mare Serenitatis (middle left), Mare Tranquillitatis (lower left), and Mare Crisium, the dark circular feature toward the bottom of the mosaic. Also visible in this view are the dark lava plains of the Marginis and Smythii Basins at the lower right. The Humboldtianum Basin, a 400-mile impact structure partly filled with dark volcanic deposits, is seen at the center of the image. Image Credit: NASA/JPL/USGS

During its mission, the Galileo spacecraft returned a number of images of Earth’s only natural satellite. Galileo surveyed the moon on Dec. 7, 1992, on its way to explore the Jupiter system in 1995-1997. 

This color mosaic was assembled from 18 images taken by Galileo’s imaging system through a green filter. On the upperleft is the dark, lava-filled Mare Imbrium, Mare Serenitatis (middle left), Mare Tranquillitatis (lower left), and Mare Crisium, the dark circular feature toward the bottom of the mosaic. Also visible in this view are the dark lava plains of the Marginis and Smythii Basins at the lower right. The Humboldtianum Basin, a 400-mile impact structure partly filled with dark volcanic deposits, is seen at the center of the image. 

Image Credit: NASA/JPL/USGS



December 08, 2009, 3:01pm

Photograph

Proctor Crater, Mars This view from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter is of the Proctor Crater. The relatively bright, small ridges are ripples. From their study on Earth, and close-up examination by the MER rovers (roving elsewhere on Mars), scientists surmise that the ripples are composed of fine sand (less than 200 microns in diameter) or fine sand coated with coarser sand and granules.The larger, darker bedforms are dunes composed of sand, most likely of fine size. Ripples tend to move slower than dunes. Because of this, over time, ripples get covered with dust, possibly explaining the bright tone visible here. The dunes are dark probably because they are composed of basaltic sand (derived from dark, volcanic rock) that is blown by the wind enough that dust does not sufficiently accumulate to change their color.This area in Proctor Crater is being monitored by HiRISE to document any changes over time.This image is a portion of the HiRISE observation taken on Feb. 9, 2009.For more information on this image, visit http://www.nasa.gov/mission_pages/MRO/multimedia/mro20090316.html.Image Credit: NASA/JPL-Caltech/University of Arizona

Proctor Crater, Mars

This view from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter is of the Proctor Crater. The relatively bright, small ridges are ripples. From their study on Earth, and close-up examination by the MER rovers (roving elsewhere on Mars), scientists surmise that the ripples are composed of fine sand (less than 200 microns in diameter) or fine sand coated with coarser sand and granules.

The larger, darker bedforms are dunes composed of sand, most likely of fine size. Ripples tend to move slower than dunes. Because of this, over time, ripples get covered with dust, possibly explaining the bright tone visible here. The dunes are dark probably because they are composed of basaltic sand (derived from dark, volcanic rock) that is blown by the wind enough that dust does not sufficiently accumulate to change their color.

This area in Proctor Crater is being monitored by HiRISE to document any changes over time.

This image is a portion of the HiRISE observation taken on Feb. 9, 2009.

For more information on this image, visit http://www.nasa.gov/mission_pages/MRO/multimedia/mro20090316.html.

Image Credit: NASA/JPL-Caltech/University of Arizona



December 08, 2009, 2:59pm

Link

MediaSCAPES Screening: Immersive & Expanded Cinema of Visual Music



December 03, 2009, 3:22pm

Link

5d @ Hammer Museum Los Angeles



December 03, 2009, 3:21pm

Photograph

The Heart Nebula Bleeds Out Into Space

The Heart Nebula Bleeds Out Into Space



Reblogged from Definite Randomness.

December 03, 2009, 2:20pm

Link

MediaSCAPES Screening: Immersive & Expanded Cinema of Visual Music



December 02, 2009, 5:10pm