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This image shows Jupiter’s south pole, as seen by NASA’s Juno spacecraft from an altitude of 32,000 miles (52,000 kilometers). The oval features are cyclones, up to 600 miles (1,000 kilometers) in diameter. Multiple images taken with the JunoCam instrument on three separate orbits were combined to show all areas in daylight, enhanced color, and stereographic projection.

Credits: NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles

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A small, faint star relatively close by is home to seven Earth-size planets with conditions that could be right for liquid water and maybe even life.

The discovery sets a record for both the most Earth-size planets and the most potentially habitable planets ever discovered around a single star.

The strange planetary system is quite compact, with all of these worlds orbiting their star closer than Mercury orbits the sun, according to a newly published report in Nature.

“If you were on the surface of one of these planets, you would see the other ones as we see the moon, or a bit smaller,” says Michaël Gillon, an astronomer at the University of Liège in Belgium. “The view would be very impressive.”

Astronomers Find 7 Earth-Size Planets Around A Nearby Star

Images: NASA/JPL-Caltech

Some 40 light-years from Earth, a planet called TRAPPIST-1e offers a heart-stopping view: brilliant objects in a red sky, looming like larger and smaller versions of our own moon. But these are no moons. They are other Earth-sized planets in a spectacular planetary system outside our own. These seven rocky worlds huddle around their small, dim, red star, like a family around a campfire. Any of them could harbor liquid water, but the planet shown here, fourth from the TRAPPIST-1 star, is in the habitable zone, the area around the star where liquid water is most likely to be detected. This system was revealed by the TRansiting Planets and PlanetIsmals Small Telescope (TRAPPIST) and NASA’s Spitzer Space Telescope. The planets are also excellent targets for NASA’s James Webb Space Telescope. Take a planet-hopping excursion through the TRAPPIST-1 system.

Dark Spot and Jovian ‘Galaxy’ - This enhanced-color image of a mysterious dark spot on Jupiter seems to reveal a Jovian “galaxy” of swirling storms. Juno acquired this JunoCam image on Feb. 2, 2017, at an altitude of 9,000 miles (14,500 kilometers) above the giant planet’s cloud tops. This publicly selected target was simply titled “Dark Spot.” In ground-based images it was difficult to tell that it is a dark storm. Citizen scientist Roman Tkachenko enhanced the color to bring out the rich detail in the storm and surrounding clouds. Just south of the dark storm is a bright, oval-shaped storm with high, bright, white clouds, reminiscent of a swirling galaxy. As a final touch, he rotated the image 90 degrees, turning the picture into a work of art.

Credits: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko

NASA SELECTS MISSION TO STUDY THE CHURNING CHAOS IN OUR MILKY WAY & BEYOND

NASA has selected a science mission that will measure emissions from the interstellar medium, which is the cosmic material found between stars. This data will help scientists determine the life cycle of interstellar gas in our Milky Way galaxy, witness the formation and destruction of star-forming clouds, and understand the dynamics and gas flow in the vicinity of the center of our galaxy.

The Galactic/Extragalactic ULDB Spectroscopic Terahertz Observatory (GUSTO) mission, led by principal investigator of the University of Arizona, Christopher Walker, will fly an ultralong-duration balloon (ULDB) carrying a telescope with carbon, oxygen and nitrogen emission line detectors. This unique combination of data will provide the spectral and spatial resolution information needed for Walker and his team to untangle the complexities of the interstellar medium, and map out large sections of the plane of our Milky Way galaxy and the nearby galaxy known as the Large Magellanic Cloud.

“GUSTO will provide the first complete study of all phases of the stellar life cycle, from the formation of molecular clouds, through star birth and evolution, to the formation of gas clouds and the re-initiation of the cycle,” said Paul Hertz, astrophysics division director in the Science Mission Directorate in Washington. “NASA has a great history of launching observatories in the Astrophysics Explorers Program with new and unique observational capabilities. GUSTO continues that tradition.”

The mission is targeted for launch in 2021 from McMurdo, Antarctica, and is expected to stay in the air between 100 to 170 days, depending on weather conditions. It will cost approximately $40 million, including the balloon launch funding and the cost of post-launch operations and data analysis.

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, is providing the mission operations, and the balloon platform where the instruments are mounted, known as the gondola. The University of Arizona in Tucson will provide the GUSTO telescope and instrument, which will incorporate detector technologies from NASA’s Jet Propulsion Laboratory in Pasadena, California, the Massachusetts Institute of Technology in Cambridge, Arizona State University in Tempe, and SRON Netherlands Institute for Space Research.

NASA’s Astrophysics Explorers Program requested proposals for mission of opportunity investigations in September 2014. A panel of NASA and other scientists and engineers reviewed two mission of opportunity concept studies selected from the eight proposals submitted at that time, and NASA has determined that GUSTO has the best potential for excellent science return with a feasible development plan.



Some intriguing exoplanets

An exoplanet or extrasolar planet is a planet that orbits a star other than the Sun. The first scientific detection of an exoplanet was in 1988. However, the first confirmed detection came in 1992; since then, and as of 1 April 2017, there have been 3,607 exoplanets discovered in 2,701 planetary systems and 610 multiple planetary systems confirmed.

1- Kepler-186f

was the first rocky planet to be found within the habitable zone – the region around the host star where the temperature is right for liquid water. This planet is also very close in size to Earth. Even though we may not find out what’s going on at the surface of this planet anytime soon, it’s a strong reminder of why new technologies are being developed that will enable scientists to get a closer look at distant worlds.

2- CoRoT 7b

The first super-Earth identified as a rocky exoplanet, this planet proved that worlds like the Earth were indeed possible and that the search for potentially habitable worlds (rocky planets in the habitable zone) might be fruitful.

3- Kepler-22b  

A planet in the habitable zone and a possible water-world planet unlike any seen in our solar system.

4- Kepler 10-b

Kepler’s first rocky planet discovery is a scorched, Earth-size world that scientists believe may have a lava ocean on its surface.

5- 55 Cancri e

55 Cancri e is a toasty world that rushes around its star every 18 hours. It orbits so closely – about 25 times closer than Mercury is to our sun – that it is tidally locked with one face forever blisters under the heat of its sun. The planet is proposed to have a rocky core surrounded by a layer of water in a “supercritical” state, where it is both liquid and gas, and then the whole planet is thought to be topped by a blanket of steam.

6- 51 Pegasi b

This giant planet, which is about half the mass of Jupiter and orbits its star every four days, was the first confirmed exoplanet around a sun-like star, a discovery that launched a whole new field of exploration.

7- Kepler-444 system

The oldest known planetary system has five terrestrial-sized planets, all in orbital resonance. This weird group showed that solar systems have formed and lived in our galaxy for nearly its entire existence.

8- PSR B1257+12 system

Discovered in 1992 and 1994, the planets that orbit pulsar PSR B1257+12 are not only the smallest planetary bodies known to exist outside our solar system, they also orbit a neutron star. These weird “pulsar planets” demonstrated that planets exist in all environments in the galaxy – even around the remnants of an exploded star.

9- HD 80606 b  

This world has the most eccentric orbit, and as one scientist put it, “wears its heart on its sleeve,” with storms, rotation, atmospheric heating, and a crazy orbit all plainly visible.

10- OGLE-2005-BLG-390

Considered to be the first cold super Earth, this exoplanet began to form a Jupiter-like core of rock and ice, but couldn’t grow fast enough in size. Its final mass is five times that of Earth. The planet’s nickname is Hoth, after a planet from Star War

Credits: NASA / JPL-Caltech

Solar System: Things to Know This Week

With only four months left in the mission, Cassini is busy at Saturn. The upcoming cargo launch, anniversaries and more!

As our Cassini spacecraft made its first-ever dive through the gap between Saturn and its rings on April 26, 2017, one of its imaging cameras took a series of rapid-fire images that were used to make this movie sequence. Credits: NASA/JPL-Caltech/Space Science Institute/Hampton University

1-3. The Grand Finale

Our Cassini spacecraft has begun its final mission at Saturn. Some dates to note:

  • May 28, 2017: Cassini makes its riskiest ring crossing as it ventures deeper into Saturn’s innermost ring (D ring).
  • June 29, 2017: On this day in 2004, the Cassini orbiter and its travel companion the European Space Agency’s Huygens probe arrived at Saturn.
  • September 15, 2017: In a final, spectacular dive, Cassini will plunge into Saturn - beaming science data about Saturn’s atmosphere back to Earth to the last second. It’s all over at 5:08 a.m. PDT.

4. Cargo Launch to the International Space Station

June 1, 2017: Target date of the cargo launch. The uncrewed Dragon spacecraft will launch on a Falcon 9 from Launch Complex 39A at our Kennedy Space Center in Florida. The payload includes NICER, an instrument to measure neutron stars, and ROSA, a Roll-Out Solar Array that will test a new solar panel that rolls open in space like a party favor.

5. Sojourner

July 4, 2017: Twenty years ago, a wagon-sized rover named Sojourner blazed the trail for future Mars explorers - both robots and, one day, humans. Take a trip back in time to the vintage Mars Pathfinder websites:

6. Voyager

August 20, 2017: Forty years and still going strong, our twin Voyagers mark 40 years since they left Earth.

7. Total Solar Eclipse

August 21, 2017: All of North America will be treated to a rare celestial event: a total solar eclipse. The path of totality runs from Oregon to South Carolina.

8. From Science Fiction to Science Fact

Light a candle for the man who took rocketry from science fiction to science fact. On this day in 1882, Robert H. Goddard was born in Worcester, Massachusetts.

9. Looking at the Moon

October 28, 2017: Howl (or look) at the moon with the rest of the world. It’s time for the annual International Observe the Moon Night.

10. Last Human on the Moon

December 13, 2017: Forty-five years ago, Apollo 17 astronaut Gene Cernan left the last human footprint on the moon.

Discover more lists of 10 things to know about our solar system HERE.

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Illusions in the Cosmic Clouds: Pareidolia is the psychological phenomenon where people see recognizable shapes in clouds, rock formations, or otherwise unrelated objects or data. There are many examples of this phenomenon on Earth and in space.

When an image from NASAs Chandra X-ray Observatory of PSR B1509-58 a spinning neutron star surrounded by a cloud of energetic particles was released in 2009, it quickly gained attention because many saw a hand-like structure in the X-ray emission.

In a new image of the system, X-rays from Chandra in gold are seen along with infrared data from NASAs Wide-field Infrared Survey Explorer telescope in red, green and blue. Pareidolia may strike again as some people report seeing a shape of a face in WISEs infrared data. What do you see?

NASAs Nuclear Spectroscopic Telescope Array, or NuSTAR, also took a picture of the neutron star nebula in 2014, using higher-energy X-rays than Chandra.

PSR B1509-58 is about 17,000 light-years from Earth.

JPL, a division of the California Institute of Technology in Pasadena, manages the WISE mission for NASA. NASAs Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandras science and flight operations.

Image Credit: X-ray: NASA/CXC/SAO; Infrared: NASA/JPL-Caltech

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Cosmic ‘Winter’ Wonderland

Although there are no seasons in space, this cosmic vista invokes thoughts of a frosty winter landscape. It is, in fact, a region called NGC 6357 where radiation from hot, young stars is energizing the cooler gas in the cloud that surrounds them. 

Located in our galaxy about 5,500 light years from Earth, NGC 6357 is actually a “cluster of clusters,” containing at least three clusters of young stars, including many hot, massive, luminous stars. The X-rays from Chandra and ROSAT reveal hundreds of point sources, which are the young stars in NGC 6357, as well as diffuse X-ray emission from hot gas. There are bubbles, or cavities, that have been created by radiation and material blowing away from the surfaces of massive stars, plus supernova explosions.

Credit: X-ray: NASA/CXC/PSU/L. Townsley et al; Optical: UKIRT; Infrared: NASA/JPL-Caltech

If all goes to plan, NASA’s Cassini spacecraft will beam new images of Saturn and its rings to Earth early Thursday, sharing data collected Wednesday from its first dive through the gap between the planet and its striped belt of ice and rock particles.

Today’s dive also marks the start of the final phase in the craft’s 13-year visit to Saturn. Days ago, it used the gravity of Saturn’s moon Titan to bend its path toward its eventual destruction on the planet.

Cassini descended below the ring plane around 5 a.m. ET Wednesday, but the antenna it would normally use to send images is instead being used to deflect potentially harmful objects away from its instruments. As it performed the move, the craft’s Twitter feed announced, “Shields Up!

Cassini Spacecraft Starts Weaving Between Saturn And Its Rings

Photo: NASA/JPL-Caltech

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Cassini Looks on as Solstice Arrives at Saturn

NASA’s Cassini spacecraft still has a few months to go before it completes its mission in September, but the veteran Saturn explorer reaches a new milestone today. Saturn’s solstice – that is, the longest day of summer in the northern hemisphere and the shortest day of winter in the southern hemisphere – arrives today for the planet and its moons. The Saturnian solstice occurs about every 15 Earth years as the planet and its entourage slowly orbit the sun, with the north and south hemispheres alternating their roles as the summer and winter poles.

Reaching the solstice, and observing seasonal changes in the Saturn system along the way, was a primary goal of Cassini’s Solstice Mission – the name of Cassini’s second extended mission.

Cassini arrived at Saturn in 2004 for its four-year primary mission to study Saturn and its rings and moons. Cassini’s first extended mission, from 2008 to 2010, was known as the Equinox Mission. During that phase of the mission, Cassini watched as sunlight struck Saturn’s rings edge-on, casting shadows that revealed dramatic new ring structures. NASA chose to grant the spacecraft an additional seven-year tour, the Solstice Mission, which began in 2010.

“During Cassini’s Solstice Mission, we have witnessed – up close for the first time – an entire season at Saturn,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory, Pasadena, California. “The Saturn system undergoes dramatic transitions from winter to summer, and thanks to Cassini, we had a ringside seat.”

Saturn

During its Solstice Mission, Cassini watched a giant storm erupt and encircle the planet. The spacecraft also saw the disappearance of bluer hues that had lingered in the far north as springtime hazes began to form there. The hazes are part of the reason why features in Saturn’s atmosphere are more muted in their appearance than those on Jupiter.

Data from the mission showed how the formation of Saturn’s hazes is related to the seasonally changing temperatures and chemical composition of Saturn’s upper atmosphere. Cassini researchers have found that some of the trace hydrocarbon compounds there – gases like ethane, propane and acetylene – react more quickly than others to the changing amount of sunlight over the course of Saturn’s year.

Researchers were also surprised that the changes Cassini observed on Saturn didn’t occur gradually. They saw changes occur suddenly, at specific latitudes in Saturn’s banded atmosphere. “Eventually a whole hemisphere undergoes change, but it gets there by these jumps at specific latitude bands at different times in the season,” said Robert West, a Cassini imaging team member at JPL.

Rings

Following equinox and continuing toward northern summer solstice, the sun rose ever higher above the rings’ northern face. And as the sun rises higher, its light penetrates deeper into the rings, heating them to the warmest temperatures seen there during the mission. The solstice sunlight helps reveal to Cassini’s instruments how particles clump together and whether the particles buried in the middle of the ring plane have a different composition or structure than the ones in the rings’ outer layers.

Saturn’s changing angle with respect to the sun also means the rings are tipped toward Earth by their maximum amount at solstice. In this geometry, Cassini’s radio signal passes more easily and cleanly through the densest rings, providing even higher-quality data about the ring particles there.

Titan

Cassini has watched Saturn’s largest moon, Titan, change with the seasons, with occasional dramatic outbursts of cloud activity. After observing methane storm clouds around Titan’s south pole in 2004, Cassini watched giant storms transition to Titan’s equator in 2010.

Although a few northern clouds have begun to appear, scientists have since been surprised at how long it has taken for cloud activity to shift to the northern hemisphere, defying climate models that had predicted such activity should have started several years earlier.

“Observations of how the locations of cloud activity change and how long such changes take give us important information about the workings of Titan’s atmosphere and also its surface, as rainfall and wind patterns change with the seasons too,” said Elizabeth Turtle, a Cassini imaging team associate at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.

In 2013, Cassini observed a sudden and rapid buildup of haze and trace hydrocarbons in the south that were previously observed only in Titan’s high north. This indicated to scientists that a seasonal reversal was underway, in which Titan’s main atmospheric circulation changes direction. This circulation was apparently channeling fresh hydrocarbon chemicals from closer to the equator toward the south pole, where they were safe from destruction by sunlight as that pole moved deeper into winter shadow.

Enceladus

For Enceladus, the most important seasonal change was the onset of winter darkness in the south. Although it meant Cassini could no longer take sunlit images of the geologically active surface, the spacecraft could more clearly observe the heat coming from within Enceladus itself. With the icy moon’s south pole in shadow, Cassini scientists have been able to monitor the temperature of the terrain there without concern for the sun’s influence.

These observations are helping researchers to better understand the global ocean that lies beneath the surface. From the moon’s south polar region, that hidden ocean sprays a towering plume of ice and vapor into space that Cassini has directly sampled.

Toward the Final Milestone

As Saturn’s solstice arrives, Cassini is currently in the final phase of its long mission, called its Grand Finale. Over the course of 22 weeks from April 26 to Sept. 15, the spacecraft is making a series of dramatic dives between the planet and its icy rings. The mission is returning new insights about the interior of the planet and the origins of the rings, along with images from closer to Saturn than ever before. The mission will end with a final plunge into Saturn’s atmosphere on Sept. 15.

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the mission for NASA’s Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter.

TOP IMAGE….These natural color views from NASA’s Cassini spacecraft compare the appearance of Saturn’s north-polar region in June 2013 and April 2017. In both views, Saturn’s polar hexagon dominates the scene. The comparison shows how clearly the color of the region changed in the interval between the two views, which represents the latter half of Saturn’s northern hemisphere spring. In 2013, the entire interior of the hexagon appeared blue. By 2017, most of the hexagon’s interior was covered in yellowish haze, and only the center of the polar vortex retained the blue color. The seasonal arrival of the sun’s ultraviolet light triggers the formation of photochemical aerosols, leading to haze formation. The general yellowing of the polar region is believed to be caused by smog particles produced by increasing solar radiation shining on the polar region as Saturn approached the northern summer solstice on May 24, 2017. Scientists are considering several ideas to explain why the center of the polar vortex remains blue while the rest of the polar region has turned yellow. One idea is that, because the atmosphere in the vortex’s interior is the last place in the northern hemisphere to be exposed to spring and summer sunlight, smog particles have not yet changed the color of the region. A second explanation hypothesizes that the polar vortex may have an internal circulation similar to hurricanes on Earth. If the Saturnian polar vortex indeed has an analogous structure to terrestrial hurricanes, the circulation should be downward in the eye of the vortex. The downward circulation should keep the atmosphere clear of the photochemical smog particles, and may explain the blue color. Images captured with Cassini’s wide-angle camera using red, green and blue spectral filters were combined to create these natural-color views. The 2013 view (left in the combined view), was captured on June 25, 2013, when the spacecraft was about 430,000 miles (700,000 kilometers) away from Saturn. The original versions of these images, as sent by the spacecraft, have a size of 512 by 512 pixels and an image scale of about 52 miles (80 kilometers) per pixel; the images have been mapped in polar stereographic projection to the resolution of approximately 16 miles (25 kilometers) per pixel. The second and third frames in the animation were taken approximately 130 and 260 minutes after the first image. The 2017 sequence (right in the combined view) was captured on April 25, 2017, just before Cassini made its first dive between Saturn and its rings. During the imaging sequence, the spacecraft’s distance from the center of the planet changed from 450,000 miles (725,000 kilometers) to 143,000 miles (230,000 kilometers). The original versions of these images, as sent by the spacecraft, have a size of 512 by 512 pixels. The resolution of the original images changed from about 52 miles (80 kilometers) per pixel at the beginning to about 9 miles (14 kilometers) per pixel at the end. The images have been mapped in polar stereographic projection to the resolution of approximately 16 miles (25 kilometers) per pixel. The average interval between the frames in the movie sequence is 230 minutes.

CENTRE IMAGE….Of the countless equinoxes Saturn has seen since the birth of the solar system, this one, captured here in a mosaic of light and dark, is the first witnessed up close by an emissary from Earth … none other than our faithful robotic explorer, Cassini. Seen from our planet, the view of Saturn’s rings during equinox is extremely foreshortened and limited. But in orbit around Saturn, Cassini had no such problems. From 20 degrees above the ring plane, Cassini’s wide angle camera shot 75 exposures in succession for this mosaic showing Saturn, its rings, and a few of its moons a day and a half after exact Saturn equinox, when the sun’s disk was exactly overhead at the planet’s equator. The novel illumination geometry that accompanies equinox lowers the sun’s angle to the ring plane, significantly darkens the rings, and causes out-of-plane structures to look anomalously bright and to cast shadows across the rings. These scenes are possible only during the few months before and after Saturn’s equinox which occurs only once in about 15 Earth years. Before and after equinox, Cassini’s cameras have spotted not only the predictable shadows of some of Saturn’s moons , but also the shadows of newly revealed vertical structures in the rings themselves. Also at equinox, the shadows of the planet’s expansive rings are compressed into a single, narrow band cast onto the planet as seen in this mosaic. The images comprising the mosaic, taken over about eight hours, were extensively processed before being joined together. First, each was re-projected into the same viewing geometry and then digitally processed to make the image “joints” seamless and to remove lens flares, radially extended bright artifacts resulting from light being scattered within the camera optics. At this time so close to equinox, illumination of the rings by sunlight reflected off the planet vastly dominates any meager sunlight falling on the rings. Hence, the half of the rings on the left illuminated by planetshine is, before processing, much brighter than the half of the rings on the right. On the right, it is only the vertically extended parts of the rings that catch any substantial sunlight. With no enhancement, the rings would be essentially invisible in this mosaic. To improve their visibility, the dark (right) half of the rings has been brightened relative to the brighter (left) half by a factor of three, and then the whole ring system has been brightened by a factor of 20 relative to the planet. So the dark half of the rings is 60 times brighter, and the bright half 20 times brighter, than they would have appeared if the entire system, planet included, could have been captured in a single image. The moon Janus (179 kilometers, 111 miles across) is on the lower left of this image. Epimetheus (113 kilometers, 70 miles across) appears near the middle bottom. Pandora (81 kilometers, 50 miles across) orbits outside the rings on the right of the image. The small moon Atlas (30 kilometers, 19 miles across) orbits inside the thin F ring on the right of the image. The brightnesses of all the moons, relative to the planet, have been enhanced between 30 and 60 times to make them more easily visible. Other bright specks are background stars. Spokes – ghostly radial markings on the B ring – are visible on the right of the image.
This view looks toward the northern side of the rings from about 20 degrees above the ring plane. The images were taken on Aug. 12, 2009, beginning about 1.25 days after exact equinox, using the red, green and blue spectral filters of the wide angle camera and were combined to create this natural color view. The images were obtained at a distance of approximately 847,000 kilometers (526,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 74 degrees. Image scale is 50 kilometers (31 miles) per pixel.


LOWER IMAGE….NASA’s Cassini spacecraft chronicles the change of seasons as it captures clouds concentrated near the equator of Saturn’s largest moon, Titan. Methane clouds in the troposphere, the lowest part of the atmosphere, appear white here and are mostly near Titan’s equator. The darkest areas are surface features that have a low albedo, meaning they do not reflect much light. Cassini observations of clouds like these provide evidence of a seasonal shift of Titan’s weather systems to low latitudes following the August 2009 equinox in the Saturnian system. (During equinox, the sun lies directly over the equator. ) In 2004, during Titan’s late southern summer, extensive cloud systems were common in Titan’s south polar region (see PIA06110, PIA06124 and PIA06241). Since 2005, southern polar systems have been observed infrequently, and one year after the equinox, extensive near-equatorial clouds have been seen. This image was taken on Oct. 18, 2010, a little more than one Earth year after the Saturnian equinox, which happens once in roughly 15 Earth years. The cloud patterns observed from late southern summer to early southern fall on Titan suggest that Titan’s global atmospheric circulation is influenced by both the atmosphere and the surface. The temperature of the surface responds more rapidly to changes in illumination than does the thick atmosphere. Outbreaks such as the clouds seen here may be the Titan equivalent of what creates the Earth’s tropical rainforest climates, even though the delayed reaction to the change of seasons and the apparently sudden shift is more reminiscent of the behavior over Earth’s tropical oceans than over tropical land areas. A few clouds can be seen in Titan’s southern latitudes here. This view looks toward the Saturn-facing side of Titan (5,150 kilometers or 3,200 miles across). North is up. The image appears slightly grainy because it was re-projected to a scale of 6 kilometers (4 miles) per pixel. Scale in the original image was 15 kilometers (9 miles) per pixel. This view consists of an average of three images taken using a filter sensitive to near-infrared light centered at 938 nanometers, which allows for detection of Titan’s surface and lower atmosphere, plus an image taken using a filter sensitive to visible light centered at 619 nanometers.
The images were taken with the Cassini spacecraft’s narrow-angle camera at a distance of approximately 2.5 million kilometers (1.6 million miles) from Titan and at a sun-Titan-spacecraft, or phase, angle of 56 degrees.


BOTTOM IMAGE….The huge storm churning through the atmosphere in Saturn’s northern hemisphere overtakes itself as it encircles the planet in this true-color view from NASA’s Cassini spacecraft.
This picture, captured on Feb. 25, 2011, was taken about 12 weeks after the storm began, and the clouds by this time had formed a tail that wrapped around the planet. Some of the clouds moved south and got caught up in a current that flows to the east (to the right) relative to the storm head. This tail, which appears as slightly blue clouds south and west (left) of the storm head, can be seen encountering the storm head in this view. This storm is the largest, most intense storm observed on Saturn by NASA’s Voyager or Cassini spacecraft. It is still active today. As scientists have tracked this storm over several months, they have found it covers 500 times the area of the largest of the southern hemisphere storms observed earlier in the Cassini mission. The shadow cast by Saturn’s rings has a strong seasonal effect, and it is possible that the switch to powerful storms now being located in the northern hemisphere is related to the change of seasons after the planet’s August 2009 equinox. Huge storms called Great White Spots have been observed in previous Saturnian years (each of which is about 30 Earth years), usually appearing in late northern summer. Saturn is now experiencing early northern spring, so this storm, if it is a Great White Spot, is happening earlier than usual. This storm is about as large as the largest of the Great White Spots, which also encircled the planet but had latitudinal sizes ranging up to 20,000 kilometers (12,000 miles). The Voyager and Cassini spacecraft were not at Saturn for previous Great White Spot appearances. The storm is a prodigious source of radio noise, which comes from lightning deep in the planet’s atmosphere. The lightning is produced in the water clouds, where falling rain and hail generate electricity. The mystery is why Saturn stores energy for decades and releases it all at once. This behavior is unlike that at Jupiter and Earth, which have numerous storms going on at all times. This view looks toward the sunlit side of the rings from just above the ring plane. Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were acquired with the Cassini spacecraft wide-angle camera at a distance of approximately 1.4 million miles (2.2 million kilometers) from Saturn. Image scale is 80 miles (129 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 Cassini-Huygens 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 team is based at the Space Science Institute in Boulder, Colo.

Saturn’s Blue Vortex

As Cassini nears the end of its mission, the spacecraft continues to beam back the most astounding images. Last week as it dove between Saturn and its rings, Cassini captured this stunning view of the planet’s beautiful blue vortex. The vortex is an 1,800 mile wide circular storm spinning around Saturn’s pole. Originally captured in black and white, this is the storm in natural color using filters. That vibrant blue is what you’d actually see due to scattering of sunlight, similar Earth’s sky. 

(Image credit: NASA/JPL-Caltech/Space Science Institute/Sophia Nasr)

Near the outskirts of the Small Magellanic Cloud, lies 5 million year old star cluster, NGC 602. Surrounded by gas and dust, NGC 602 is featured in this stunning optical Hubble image of the region, is a combination of images in the X-ray by Chandra, and in the infrared by Spitzer. Fantastic ridges and swept back shapes strongly suggest that energetic radiation and shock waves from NGC 602’s massive young stars have eroded the dusty material and triggered a progression of star formation moving away from the cluster’s center. The background galaxies are hundreds of millions of light-years or more beyond NGC 602.

Image Credit: X-ray: Chandra: NASA/CXC/Univ.Potsdam/L.Oskinova et al;
Optical: Hubble: NASA/STScI; Infrared: Spitzer: NASA/JPL-Caltech