Category Archives: Space Science

Images of dunes and gullies on a Mars crater wall

The Mars Reconnaissance Orbiter sends a terrific view of dunes and gullies formed on a crater wall on the Red Planet:

The Contrasting Colors of Crater Dunes and Gullies 

Gullies are relatively common features in the steep slopes of crater walls, possibly formed by dry debris flows, movement of carbon dioxide frost, or perhaps the melting of ground ice.

This example shows a section of crater wall from the rocky crater rim at the far left of the image, down to the dark dusty dunes on the crater floor in the bottom right. (North is to the left.) The rock of the crater walls shows up deep orange, and the sandy deposits on the crater floor and the base of the crater walls appear blue. The sand isn’t really blue; the different colors in this image represent different material compositions.

The gullies in this image have two main sections: a scalloped alcove at the top of the gully (left/center), and defined channel sections further down the crater wall (right/center). Material from the alcove will have traveled down the channel to the crater floor. This normally forms a third section to a typical gully, a debris fan. Fans commonly visible at the base of gullies are not obvious in this example however, as the wind blown sediments (blue) have covered the crater floor after gully formation.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA’s Science Mission Directorate, Washington.

Hi-Rise raw image. Click for larger version

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Cassini views the little moon Daphnis up close

In early January, the Cassini spacecraft took this marvelous shot of the small moon Daphnis as it travels along in a gap in Saturn’s rings: Cassini: Mission to Saturn: Daphnis Up Close 

The wavemaker moon, Daphnis, is featured in this view, taken as NASA’s Cassini spacecraft made one of its ring-grazing passes over the outer edges of Saturn’s rings on Jan. 16, 2017. This is the closest view of the small moon obtained yet. Daphnis (5 miles or 8 kilometers across) orbits within the 42-kilometer (26-mile) wide Keeler Gap. Cassini’s viewing angle causes the gap to appear narrower than it actually is, due to foreshortening. The little moon’s gravity raises waves in the edges of the gap in both the horizontal and vertical directions. Cassini was able to observe the vertical structures in 2009, around the time of Saturn’s equinox. [Full caption and larger images]
Check out the latest Cassini shots from the Saturnian system in the Mission to Saturn Images gallery and the Raw Images gallery

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Cassini returns detailed views of Saturn’s rings

NASA’s Cassini probe at Saturn returns amazing views of the outer rings as it makes its final orbits before plunging into the planet’s atmosphere on September 15th :

Close Views Show Saturn’s Rings in Unprecedented Detail

Newly released images showcase the incredible closeness with which NASA’s Cassini spacecraft, now in its “Ring-Grazing” orbits phase, is observing Saturn’s dazzling rings of icy debris.

This Cassini image features a density wave in Saturn’s A ring (at left) that lies around 134,500 km from Saturn. Density waves are accumulations of particles at certain distances from the planet. This feature is filled with clumpy perturbations, which researchers informally refer to as “straw.” Image Credit: NASA/JPL-Caltech/Space Science Institute › Full image and caption

The views are some of the closest-ever images of the outer parts of the main rings, giving scientists an eagerly awaited opportunity to observe features with names like “straw” and “propellers.” Although Cassini saw these features earlier in the mission, the spacecraft’s current, special orbits are now providing opportunities to see them in greater detail. The new images resolve details as small as 0.3 miles (550 meters), which is on the scale of Earth’s tallest buildings.

Cassini is now about halfway through its penultimate mission phase — 20 orbits that dive past the outer edge of the main ring system. The ring-grazing orbits began last November, and will continue until late April, when Cassini begins its grand finale. During the 22 finale orbits, Cassini will repeatedly plunge through the gap between the rings and Saturn. The first finale plunge is scheduled for April 26.

This image from NASA’s Cassini mission shows a region in Saturn’s A ring. The level of detail is twice as high as this part of the rings has ever been seen before. The view contains many small, bright blemishes due to cosmic rays and charged particle radiation near the planet. Image Credit: NASA/JPL-Caltech/Space Science Institute › Full image and caption

For now, the veteran spacecraft is shooting past the outer edges of the rings every week, gathering some of its best images of the rings and moons. Already Cassini has sent back the closest-ever views of small moons Daphnis and Pandora.

Some of the structures seen in recent Cassini images have not been visible at this level of detail since the spacecraft arrived at Saturn in mid-2004. At that time, fine details like straw and propellers — which are caused by clumping ring particles and small, embedded moonlets, respectively — had never been seen before. (Although propellers were present in Cassini’s arrival images, they were actually discovered in later analysis, the following year.)

This image shows a region in Saturn’s outer B ring. NASA’s Cassini spacecraft viewed this area at a level of detail twice as high as it had ever been observed before. And from this view, it is clear that there are still finer details to uncover. Image Credit: NASA/JPL-Caltech/Space Science Institute › Full image and caption

Cassini came a bit closer to the rings during its arrival at Saturn, but the quality of those arrival images (examples: 1, 2, 3) was not as high as in the new views. Those precious few observations only looked out on the backlit side of the rings, and the team chose short exposure times to minimize smearing due to Cassini’s fast motion as it vaulted over the ring plane. This resulted in images that were scientifically stunning, but somewhat dark and noisy.

In contrast, the close views Cassini has begun capturing in its ring-grazing orbits (and soon will capture in its Grand Finale phase) are taking in both the backlit and sunlit side of the rings. Instead of just one brief pass lasting a few hours, Cassini is making several dozen passes during these final months.

“As the person who planned those initial orbit-insertion ring images — which remained our most detailed views of the rings for the past 13 years — I am taken aback by how vastly improved are the details in this new collection,” said Cassini Imaging Team Lead Carolyn Porco, of Space Science Institute, Boulder, Colorado. “How fitting it is that we should go out with the best views of Saturn’s rings we’ve ever collected.”

After nearly 13 years studying Saturn’s rings from orbit, the Cassini team has a deeper, richer understanding of what they’re seeing, but they still anticipate new surprises.

“These close views represent the opening of an entirely new window onto Saturn’s rings, and over the next few months we look forward to even more exciting data as we train our cameras on other parts of the rings closer to the planet,” said Matthew Tiscareno, a Cassini scientist who studies Saturn’s rings at the SETI Institute, Mountain View, California. Tiscareno planned the new images for the camera team.

Launched in 1997, Cassini has been touring the Saturn system since arriving in 2004 for an up-close study of the planet, its rings and moons, and its vast magnetosphere. Cassini has made numerous dramatic discoveries, including a global ocean with indications of hydrothermal activity within the moon Enceladus, and liquid methane seas on another moon, Titan.

This image shows a region in Saturn’s outer B ring. NASA’s Cassini spacecraft viewed this area at a level of detail twice as high as it had ever been observed before. Image Credit: NASA/JPL-Caltech/Space Science Institute › Full image and caption

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA’s Jet Propulsion Laboratory in Pasadena, California, manages the mission for the agency’s Science Mission Directorate in Washington. JPL is a division of Caltech in Pasadena. The Cassini imaging operations center is based at Space Science Institute in Boulder, Colorado.

For more information about Cassini, visit:

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Video: New Horizons bring you in for a ‘landing’ on Pluto

In this video, color corrected images from the New Horizons probe are presented in sequence to bring you closer and closer to the surface of Pluto: A Colorful ‘Landing’ on Pluto – New Horizons

From the caption:

What would it be like to actually land on Pluto? This movie was made from more than 100 images taken by NASA’s New Horizons spacecraft over six weeks of approach and close flyby in the summer of 2015. The video offers a trip down onto the surface of Pluto — starting with a distant view of Pluto and its largest moon, Charon — and leading up to an eventual ride in for a “landing” on the shoreline of Pluto’s informally named Sputnik Planitia.

To create a movie that makes viewers feel as if they’re diving into Pluto, mission scientists had to interpolate some of the panchromatic (black and white) frames based on what they know Pluto looks like to make it as smooth and seamless as possible. Low-resolution color from the Ralph color camera aboard New Horizons was then draped over the frames to give the best available, actual color simulation of what it would look like to descend from high altitude to Pluto’s surface.

After a 9.5-year voyage covering more than three billion miles, New Horizons flew through the Pluto system on July 14, 2015, coming within 7,800 miles (12,500 kilometers) of Pluto. Carrying powerful telescopic cameras that could spot features smaller than a football field, New Horizons sent back hundreds of images of Pluto and its moons that show how dynamic and fascinating their surfaces are. Credits: NASA/JHUAPL/SwRI

The original black-and-white “landing” movie can be viewed at:
http://pluto.jhuapl.edu/News-Center/N…

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Help choose Juno’s next image targets on Jupiter

Help select spots on Jupiter for the Juno spacecraft to image on its next pass close to the planet:

Public to Choose Jupiter Picture Sites for NASA Juno 

This amateur-processed image was taken on Dec. 11, 2016, at 9:27 a.m. PST (12:27 p.m. EST), as NASA’s Juno spacecraft performed its third close flyby of Jupiter. At the time the image was taken, the spacecraft was about 15,200 miles (24,400 kilometers) from the gas giant planet. The citizen scientist (Eric Jorgensen) cropped the JunoCam image and enhanced the color to draw attention to Jupiter’s swirling clouds southeast of the “pearl.” The “pearl” is one of eight massive rotating storms at 40 degrees south latitude on Jupiter, known colloquially as the “string of pearls.” The processing of this image highlights the turbulence of the clouds in the south temperate belt of the planet. [Other image sizes]
Where should NASA’s Juno spacecraft aim its camera during its next close pass of Jupiter on Feb. 2? You can now play a part in the decision. For the first time, members of the public can vote to participate in selecting all pictures to be taken of Jupiter during a Juno flyby. Voting begins Thursday, Jan. 19 at 11 a.m. PST (2 p.m. EST) and concludes on Jan. 23 at 9 a.m. PST (noon EST).

“We are looking forward to people visiting our website and becoming part of the JunoCam imaging team,” said Candy Hansen, Juno co-investigator from the Planetary Science Institute, Tucson, Arizona. “It’s up to the public to determine the best locations in Jupiter’s atmosphere for JunoCam to capture during this flyby.”

NASA’s JunoCam website can be visited at: www.missionjuno.swri.edu/junocam

The voting page for this flyby is available at: www.missionjuno.swri.edu/junocam/voting/

JunoCam will begin taking pictures as the spacecraft approaches Jupiter’s north pole. Two hours later, the imaging will conclude as the spacecraft completes its close flyby, departing from below the gas giant’s south pole. Juno is currently on its fourth orbit around Jupiter. It takes 53 days for Juno to complete one orbit.

“The pictures JunoCam can take depict a narrow swath of territory the spacecraft flies over, so the points of interest imaged can provide a great amount of detail,” said Hansen. “They play a vital role in helping the Juno science team establish what is going on in Jupiter’s atmosphere at any moment. We are looking forward to seeing what people from outside the science team think is important.”

There will be a new voting page for each upcoming flyby of the mission. On each of the pages, several points of interest will be highlighted that are known to come within the JunoCam field of view during the next close approach. Each participant will get a limited number of votes per orbit to devote to the points of interest he or she wants imaged. After the flyby is complete, the raw images will be posted to the JunoCam website, where the public can perform its own processing.

“It is great to be able to share excitement and science from the Juno mission with the public in this way,” said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. “Amateur scientists, artists, students and whole classrooms are providing the world with their unique perspectives of Jupiter. I am really pleased that this website is having such a big impact and allowing so many people to join the Juno science team. The public involvement is really affecting how we look at the most massive planetary inhabitant in our solar system.”

During the Feb. 2 flyby, Juno will make its closest approach to Jupiter at 4:58 a.m. PST (7:58 a.m. EST), when the spacecraft is about 2,700 miles (4,300 kilometers) above the planet’s swirling clouds.

JunoCam is a color, visible-light camera designed to capture remarkable pictures of Jupiter’s poles and cloud tops. As Juno’s eyes, it will provide a wide view of Jupiter over the course of the mission, helping to provide context for the spacecraft’s other instruments. JunoCam was included on the spacecraft primarily for public engagement purposes, although its images also are helpful to the science team.

NASA’s Jet Propulsion Laboratory, Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for NASA’s Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of Caltech in Pasadena, California.

More information on the Juno mission is available at:

The public can follow the mission on Facebook and Twitter at:

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