Tag Archives: saturn

Radar Probes Titan’s Seas and Magic Islands

The Cassini Space Probe has measured the depth of a 40-kilometer-long stretch of Kraken Mare, the largest sea on Saturn’s moon Titan.

Shortly before capturing the first images showing Titan’s hydrocarbon seas with sunlight bouncing off of them, Cassini used radar to measure a strip of Kraken’s eastern side. Depths varied from 20 to 35 meters, but NASA cautions that these may be far from the deepest parts of the sea. 

The area studied during the August flyby is near the mouth of what on Earth would be considered a flooded river valley. Even though Titan’s rivers and seas are filled with hydrocarbons, probably methane and ethane rather than water, it is thought the processes of erosion and flooding are similar.

The study was part of a 200 kilometer sweep across the breadth of Kraken, but for the majority of this the results came back blank. NASA concluded that, “For the areas in which Cassini did not observe a radar echo from the seafloor, Kraken Mare might be too deep for the radar beam to penetrate.” An alternative possibility is that the still unknown make up of Titan’s seas varies, and the blank stretches represent more absorbent liquids.

The land around parts of the Kraken sea is quite steep, and if this continues beneath the surface, some sections might be deep enough to host the mythical beasts after which it is named.

At the same time, two bright features were seen in Kraken Mare that had not been visible on previous flybys. These may be related to the mysterious feature dubbed “magic island” that was spotted with a radar in Ligeia Mare last July before disappearing again a few days later. 

This time, however, both the Cassini radar and Visible and Infrared Mapping Spectrometer (VIMS) were focused on the right location, bolstering the opportunity to identify what causes these bright spots. Patches of waves or some form of debris are currently the favored explanations, with some alternatives such as fog or submarine icebergs having been ruled out.

The findings were presented to a workshop at the Planetary Sciences Division of the American Astronomical Society.

In January, NASA plans to do another radar sweep of Punga Mare, the smallest of the three bodies large enough to be designated seas. The same pass will provide an opportunity for researchers to study Ligeia for further clues as to the nature of these intermittent bright spots. This will be the last attempt to study Titan’s seas and sea floors before Cassini makes its final dive into Saturn to collect as much data as it can on the atmosphere of our solar system’s second largest planet before being crushed to oblivion.

H/T Space.com

Read more: http://www.iflscience.com/space/radar-probes-titans-seas-and-magic-islands

Newly-Released Maps of Saturn’s Moons Are The Clearest Ever Created

In the decade that the Cassini spacecraft has been orbiting Saturn, it has returned some pretty incredible images. Highlights include a clear view of Saturn’s hexagonal storm at the north pole, Saturn and a crescent Titan, and sunlight reflecting off of Titan’s seas. The latest addition to Cassini’s impressive portfolio is a collection of the most detailed colored maps of six of Saturn’s largest icy moons, excluding Titan. The images were taken throughout Cassini’s mission and were processed by Paul Schenk at the Lunar and Planetary Institute in Texas. 

“Getting feature locations in planetary images is a complex business,” Schenk wrote on his blog, StereoMoons. In the blog post, he discusses the challenges of sifting through all of the images to make a cohesive mosaic map.

Some of the images obtained by Cassini used colors that exist outside of normal human vision. Utilizing the near-infrared and ultraviolet wavelengths revealed structures that could not be seen otherwise. Differences in color that can be seen within our visual spectrum depict charged particles, gas, and dust that are being vented from the planet. The differences in color is predicted to be due to differences in thickness of those features.

Though these maps are quite exceptional, they aren’t completely finished. The area surrounding the north pole of Enceladus and a couple of regions on Iapetus require more imaging, which Cassini is expected to complete in 2015.

Having detailed maps of the moons’ topography will be important for future research. Knowing where landmarks exist on these satellites will give scientists a frame of reference when studying key features, in addition to allowing them to track any geological changes that occur on the surface of the moons. Future missions that may require the use of a lander are more likely to be successful if possible landing sites can be identified ahead of time and the terrain is well-understood. This has the potential to save a considerable amount of time and money.

Cassini’s primary mission ended on July 30, 2008, but had been extended twice. The orbiter is expected to remain operational until it runs out of fuel in 2017. Cassini will be directed to enter Saturn’s atmosphere at the end of its mission. Because the moons Titan and Enceladus are two of the top candidates for possible extraterrestrial life, Cassini’s operators do not want to risk the spacecraft accidentally contaminating those locations.

Mimas

NASA / JPL-Caltech / Space Science Institute / Lunar and Planetary Institute

Enceladus

NASA / JPL-Caltech / Space Science Institute / Lunar and Planetary Institute

Tethys

NASA / JPL-Caltech / Space Science Institute / Lunar and Planetary Institute

Dione

NASA / JPL-Caltech / Space Science Institute / Lunar and Planetary Institute

Rhea

NASA / JPL-Caltech / Space Science Institute / Lunar and Planetary Institute

Iapetus

NASA / JPL-Caltech / Space Science Institute / Lunar and Planetary Institute

If you’d like to see these maps with a side-by-side comparison of maps generated from Voyager data from the early 1980s, check it out on JPL’s website.

Credit: Global maps of Saturnian moons Mimas, Enceladus, Tethys, Dione, Rhea, Iapetus were produced by Dr. Paul Schenk (Lunar and Planetary Institute, Houston, TX) Image data are from the Imaging Science Subsystem (ISS) camera on the Cassini orbiter (NASA, JPL).

[Hat tip: Space.com]

Read more: http://www.iflscience.com/space/newly-released-maps-saturn-s-moons-are-clearest-ever-created

Saturn’s Glorious Rings Dazzle in NASA Photo

Saturn-s-glorious-rings-dazzle-in-nasa-photo-ff06083381

Saturn’s southern reaches are draped in the shadow of the huge planet’s iconic ring system in a spectacular new picture from NASA’s Cassini spacecraft.

The near-infrared photo, which Cassini snapped on June 15, looks toward the southern, unlit side of Saturn’s rings from 14 degrees below the ringplane, researchers said. The spacecraft was about 1.8 million miles from Saturn at the time. The image scale is 11 miles per pixel.

Saturn’s ice-covered moon Enceladus, which is 313 miles wide, is visible as a tiny, bright speck in the lower lefthand corner of the image.

Many researchers regard Enceladus as one of the best bets in our solar system to host life beyond Earth. Though surface temperatures on the moon are frigid, Enceladus is believed to harbor a vast ocean of liquid water beneath its icy shell.

Enceladus also boasts huge amounts of internal heat, which power a system of geysers that erupt from the moon’s south polar regions. Cassini discovered these geysers in 2005 and has snapped many photos of them since.

The $3.2 billion Cassini mission is a collaboration involving NASA, the European Space Agency and the Italian Space Agency. The spacecraft launched in 1997 and arrived at Saturn in 2004. It has been studying the ringed planet and its many moons ever since, and should continue to do so for years to come. The Cassini mission has been extended to at least 2017.

In early 2005, Cassini’s Huygens lander, an ESA probe, touched down on the enormous moon Titan and relayed the first photos ever from the surface of that intriguing world.

Titan has a thick, nitrogen-dominated atmosphere and a weather system based on methane and ethane, which have pooled to form lakes in various places across the moon’s surface.

This article originally published at Space.com
here

Read more: http://mashable.com/2012/10/01/saturn-rings-nasa-photo/

50-Mile Landslides Spotted on Saturn’s Icy Moon

50-mile-landslides-spotted-on-saturn-s-icy-moon-ba6c3cfc6c

Long landslides spotted on Saturn’s moon, Iapetus, could help provide clues to similar movements of material on Earth. Scientists studying the icy satellite have determined that flash heating could cause falling ice to travel 10 to 15 times farther than previously expected on Iapetus.

Extended landslides can be found on Mars and Earth, but are more likely to be composed of rock than ice. Despite the differences in materials, scientists believe there could be a link between the long-tumbling debris on all three bodies.

“We think there’s more likely a common mechanism for all of this, and we want to be able to explain all of the observations,” lead scientist Kelsi Singer of Washington University told SPACE.com.

Rock-Hard Ice on Saturn’s Moon

Giant landslides stretching as far as 50 miles litter the surface of Iapetus. Singer and her team identified 30 such displacements by studying images taken by NASA’s Cassini spacecraft.

More From Space.com: Photos: Latest Saturn Photos from NASA’s Cassini Orbiter

Composed almost completely of ice, Iapetus already stands out from other moons. While most bodies in the solar system have rocky mantles and metallic cores, with an icy layer on top, scientists think Iapetus is composed almost completely of frozen water. There are bits of rock and carbonaceous material that make half the moon appear darker than the other, but this seems to be only a surface feature.

Ice on Iapetus is different from ice found on Earth. Because the moon’s temperature can get as low as 300 degrees Fahrenheit, the moon’s ice is very hard and very dry.

“It’s more like what we experience on Earth as rock, just because it’s so cold,” Singer said.

Slow-moving ice creates a lot of friction, so when the ice falls from high places, scientists expected that it would behave much like rock on Earth does. Instead, they found that it traveled significantly farther than predicted.

How far a landslide runs is usually related to how far it falls, Singer explained. Most of the time, debris of any type loses energy before traveling twice the distance it fell from. But on Iapetus, the pieces of ice move 20 to 30 times as far as their falling height.

Flash heating could be providing that extra push.

Flash heating occurs when material falls so fast that the heat doesn’t have time to dissipate. Instead, it stays concentrated in small areas, reducing the friction between the sliding objects and allowing them to travel faster and farther than they would under normal conditions.

“They’re almost acting more like a fluid,” Singer said.

On Iapetus, falling material has a good chance of reaching great speeds because there are a number of great heights to fall from. The moon hosts a ring of mountains around its bulging equator that can tower as high as 12 miles, and the longest run-outs discovered are associated with the ridge and with impact-basin walls.

Scientists think that the landslides are relatively recent, and could have been triggered by impacts in the last billion years or so.

“You don’t see a lot of small craters on the landslide material itself,” Singer said, although the surrounding terrain boasts evidence of bombardment. Over time, landscapes tend to be dotted by falling rocks, so the less cratered a surface is, the younger it is thought to be.

More From Space.com: Photos of Saturn’s Moons

Resting on the ridges and walls, the material gradually becomes more unstable. Close impacts could set them off, but powerful, distant impacts reverberating through the ice could also send them tumbling.

The research was published in the July 29 issue of the journal Nature Geoscience.

Connecting Ice and Rock

Differences in gravity, atmosphere and water content make landslides seen on Iapetus difficult to duplicate in the laboratory. But the fact that they happen on different types of worlds makes it more likely that the mechanism triggering the extended slide is dependent on things unique to either environment.

“We have them on Iapetus, Earth and Mars,” Singer said. “Theoretically, they should be very similar.”

Singer pointed out the implications for friction within fault lines, which produces earthquakes. As plates on Earth move, the rocks within a fault snag on each other, until forces drag them apart.

But sometimes, the faults slip farther than scientists can explain based on their understanding of friction. If flash heating occurs within the faults, it could explain why the two opposing faces slide the way they do, and provoke a better understanding of earthquakes.

In such cases, flash heating would cause minerals to melt and reform, producing an unexpected material around the faults. Some such materials have been identified at the base of long landslides on Earth.

“If something else is going on, like flash heating, or something making [the material] have a lower coefficient of friction, this would affect any models that use the coefficient of friction,” Singer said.

Image courtesy of NASA/JPL/Space Science Institute

This article originally published at Space.com
here

Read more: http://mashable.com/2012/07/30/saturn-moon-landslide/

See Venus and Saturn Shine Together Early Tuesday

See-venus-and-saturn-shine-together-early-tuesday-a2f7f352cc

Early Tuesday morning (Nov. 27), you’ll be able to watch two planets that will pass each other in the dawn.

The planets in question are Venus and Saturn. One planet will be slowly descending into eventual obscurity, while the other will become increasingly prominent in the days and weeks to come.

Look for Venus and Saturn shortly after 4:30 a.m. local time. The planets will appear very low above the east-southeast horizon, weather permitting. Brilliant Venus, shining with a steady silvery-white glow, will be passing about 0.6 degrees below and to the right of the much dimmer and yellower Saturn. (Your closed fist held at arm’s length covers 10 degrees of the night sky.)

About an hour later, at 5:30 a.m. local time, Saturn will high enough for good views through a telescope of its breathtakingly beautiful rings. The tilt of the rings continues to slowly increase and is now almost 18 degrees from edgewise. As for Venus, it displays a rather small gibbous shaped disk, 87% illuminated by the sun. Venus is about 70% brighter than Saturn’s larger, but duller, disk and rings.

After Tuesday morning’s rendezvous, which is known as a conjunction, the two planets will slowly go their separate ways.

Venus, which was so prominent during the summertime, is now rising later and appearing lower to the horizon in the dawn twilight. It has about another two months to go before it ultimately drops down into the bright morning twilight and disappears from our view, eventually transitioning into the evening sky by early next spring.

Saturn, on the other hand, will climb progressively higher and rise earlier, eventually becoming a prominent and well-placed evening object by the middle of spring.

If you look at both Venus and Saturn through a telescope, Venus is unquestionably the brighter of the two objects. But you might wonder how this is possible. After all, both planets are perpetually covered with clouds and their respective albedos — the proportion of the incident sunlight reflected by those clouds — are exactly the same at 76%.

Why then does Saturn appear so much duller than Venus if both are reflecting the same proportion of sunlight back toward the Earth?

The key is their distances from the sun. Compared to Venus, Saturn is 13.59 times farther away from the sun. And if we use the inverse square law — which states that the intensity of reflected sunlight is inversely proportional to the square of the distance from the sun — then 13.59 multiplied by 13.59 shows that sunlight striking Saturn’s cloud tops, is 184.69 times weaker compared to sunlight striking the cloud tops of Venus.

In any case, arise early on Tuesday and take a peek as the Venus, the Goddess of Beauty, snuggles up to Saturn, the God of Time.

Homepage image via iStockphoto, fpm.

This article originally published at Space.com
here

Read more: http://mashable.com/2012/11/26/watch-venus-saturn/

Amazing Photo Shows Saturn Dwarfing Tiny Moon

Amazing-photo-shows-saturn-dwarfing-tiny-moon-ac3d572f4c

A jaw-dropping picture of the planet Saturn was recently released by NASA’s Cassini probe orbiting the ringed giant.

The black-and-white photo shows the gas giant tilted, with its iconic rings draping striking shadows against the planet’s atmosphere.

A faint dot in the top middle of the image, which you might be forgiven for thinking was a speck on your monitor, is actually Saturn’s moon Mimas. The moon, at 246 miles (396 kilometers) across, is dwarfed by its much larger parent. When seen up close, Mimas is dominated by a giant crater on one side that gives it a strong resemblance to the Death Star in the “Star Wars” films.

The darker dapples along Saturn‘s face are violent storms that rage in the planet’s hydrogen and helium atmosphere, researchers said.

Cassini’s view of Saturn looks up at the unilluminated side of its rings from an angle of about 18 degrees below the ring plane. The north side of the planet itself is up and rotated 27 degrees to the left.

Cassini launched in 1997 along with the Huygens lander. Cassini arrived at Saturn in 2004 and dropped Huygens onto the surface of Saturn’s huge moon Titan in January 2005. The Cassini-Huygens mission is a joint project of NASA, the European Space Agency and the Italian Space Agency.

Just last month, Cassini celebrated the 15th anniversary of its launch, and it has logged more than 3.8 billion miles (6.1 billion km) during its time in space. The probe has taken more than 300,000 images of the Saturnian system, which includes the ringed planet and its more than 60 known moons.

This article originally published at Space.com
here

Read more: http://mashable.com/2012/11/07/saturn-tiny-moon-photo/

Mark Your Calendar for Spring Meteor Showers and Eclipses

Lunar-eclipse

As the Moon passed almost directly through the center of Earth’s shadow on July 16th, sky gazers in the Pacific hemisphere were graced by a lingering lunar eclipse.

From eclipses and planets to meteor showers galore, the northern spring season of 2014 will bring a number of eye-catching celestial sights for stargazers on Earth.

Weather permitting, some of the best spring night sky events could be readily visible without the aid of binoculars or a telescope, even from brightly-lit cities. But you’ll need to know when and where to look to make the most of the season.

I’ve always felt that many astronomers started their careers as perceptive children who responded to the thrill of witnessing a noteworthy astronomical event. So whether you want to impress a youngster, or you’re simply hoping to witness a head-turning astronomical event for yourself, it always helps to be ready in advance by marking your calendar and highlighting a number of these special dates:

April 14 and 15: Mars’ closest approach in 2014 and a total eclipse of the moon

During the overnight hours of April 14 and 15, it will be a night for viewing first Mars and later the full moon.

First, Mars will come to within 57.4 million miles of our planet, making its closest approach to us since Jan. 3, 2008. All through the night, Mars will resemble a dazzling star shining with a steady fiery-colored tint making it a formidable sight; its brightness will match Sirius, the brightest of all the stars.

As a bonus, later that very same night (actually during the early hours of April 15) North America will have a ringside seat to see a total lunar eclipse when the Full Moon becomes transformed into a mottled reddish ball for 78 minutes as it becomes completely immersed in the shadow of the Earth.

This total lunar eclipse will be the first one widely visible from North America in nearly 3.5 years. The Americas will have the best view of this eclipse, although over the Canadian Maritimes, moonset will intervene near the end of totality. Of special interest is the fact that the moon will appear quite near to the bright star Spica, in the constellation Virgo, during the eclipse. They actually will be in conjunction a couple of hours prior to the onset of totality, but they’re still relatively near to each other when the eclipse gets underway.

April 22: The Lyrid meteor shower

Rather favorable circumstances are expected for this year’s Lyrid meteor shower, predicted to be at maximum this morning. The radiant, located near the brilliant bluish-white star Vega, rises in the northeast about the time evening twilight ends, and viewing will improve until light from the last-quarter moon begins to interfere just after 2 a.m. your local time.

Under the best conditions, 10 to 15 members of this shower can be seen in an hour by a single observer. The Lyrids remain about a quarter of their peak number for about two days. These bright meteors are associated with Thatcher’s Comet of 1861.

April 28 and 29: A Ring Eclipse that nobody will see?

It is quite possible that only penguins will witness the annular solar eclipse, also known as a “ring of fire” solar eclipse. That’s because it will occur within the uninhabited region of Wilkes Land in Antarctica.

Those living in southernmost parts of Indonesia as well as Australia (where it will be autumn) will at least get a view of a partial eclipse of the sun. Because the axis of the moon’s antumbral shadow misses the Earth and only its edge grazes Antarctica, it makes an accurate prediction of the duration of annularity all but impossible.

May 6: The Eta Aquarid meteor shower

The annual Eta Aquarid meteor shower — “shooting stars” spawned by the famed Halley’s Comet — is scheduled to reach maximum early this morning. It’s usually the year’s richest meteor display for Southern Hemisphere observers, but north of the equator the Eta Aquarid shower is one of the more difficult annual displays to observe.

From mid-northern latitudes, the radiant (from where the meteors appear to emanate) rises about 1:30 a.m. local daylight time, scarcely two hours before morning twilight begins to interfere. At peak activity, about a dozen shower members can be seen per hour by a single observer with good sky conditions from latitude 26 degrees North, but practically zero north of latitude 40 degrees. The shower remains active at roughly one-half peak strength for a couple of days before and after the maximum. Conditions this year are excellent; the moon is absent from the predawn sky for more than a week around maximum.

May 10: Saturn at opposition

The ringed planet Saturn reaches opposition; it rises in the east-southeast at dusk, is due south in the middle of the night and sets in the west-southwest at dawn. Once it gains enough altitude, it appears similarly as bright as the zero-magnitude stars Arcturus and Vega.

Saturn’s famous rings appear much more impressive than in recent years, since they are now tipped by 21.5 degrees from edge on.

May 24: Possible outburst of bright meteors

Perhaps the most dramatic sky event in 2014 could come at the start of the Memorial Day weekend. In the predawn hours of Saturday, May 24, our planet is expected to sweep through a great number of dusty trails left behind in space by the small comet P/209 LINEAR.

This unusual cosmic interaction might possibly result in an amazing, albeit brief display of meteors — popularly known as “shooting stars” — perhaps numbering in the many dozens . . . or even hundreds per hour. Nobody knows exactly how many meteors will be seen, but several meteor scientists believe that because the particles will be unusually large, the meteors will be outstandingly bright.

May 25: Mercury attains its greatest elongation

The planet Mercury will reach its greatest elongation, or greatest angular distance, east of the sun on this night. This is Mercury’s best evening apparition of the year; it sets about 100 minutes after sunset. An hour after sunset, look low above the west-northwest horizon; the speedy planet should be easily visible as a yellowish “star.”

Mercury will appear somewhat brighter up to two weeks before this date, and noticeably dimmer for about a week afterwards.

This article originally published at Space.com
here

Read more: http://mashable.com/2014/04/01/spring-stargazing-guide/

This Stunning Image Of Saturn’s Rings Contains A Surprise

If youre confused by this image, we dont blame you. What youre seeing here are the rings of Saturn and the gas giant itself. But the planets rings are, well, rings. Why do they appear to be criss-crossing each other here?

The answer is a pretty awesome illusion, snapped by the Cassini spacecraft thats currently in orbit around Saturn. The bulk of the image is the rings itself, while in the background is the planet Saturn. The lines going the other direction to the rings are actually the shadow of the rings on the planet, visible because the rings are semi-transparent.

Thats not the only surprising thing about this image, though. Take a look just below the middle, and youll spot a gap in one of the rings with a white dot in it. This gap is known as the Encke gap, and the white dot is the moon Pan (28 kilometers/17 miles across). Moons like this form gaps by cleaning out debris from the rings.

Now you see it… NASA/JPL-Caltech/Space Science Institute

Cassini took this image from a distance of 1.9 million kilometers (1.2 million miles) from Pan on February 11, 2016, with a scale of 10 kilometers (6 miles) per pixel. The spacecraft arrived in orbit around Saturn in 2004, and since then it has provided uswith incredible views and data from Saturn and its various moons, including Enceladus and Titan.

But, sadly, all good things must come to an end. On September 15 next year, the spacecraft will be sent to its death in the atmosphere of Saturn. This is because, as it runs out of fuel, NASA wants to ensure it wont accidentally hit one of the potentially life-harboring moons and contaminate it with material from Earth.

Dont despair too much, though, because this final death plunge will see Cassini return some groundbreaking science to Earth. Itll be sending back data constantly until its final moments, so well get incredible data from within Saturns rings and from its upper atmosphere as well something weve never gotten before.

Until then, bask in the glory of images like these. With no other spacecraft to Saturn currently in the works, we really shouldn’t take Cassini for granted.

Here’s the full image in all its glory.NASA/JPL-Caltech/Space Science Institute

Photo Gallery

Read more: http://www.iflscience.com/space/stunning-image-saturn-contains-more-one-surprise

Titan’s Sunsets Give Insight To Hazy Atmospheres of Exoplanets

Certain characteristics of exoplanets can be difficult to study due to their atmospheres obscuring details. NASA scientists have begun to Saturn’s moon Titan at sunset, in the hope that it will help them to understand the haze from the atmosphere and what it could reveal about surface conditions. The study was led by Tyler Robinson of NASA’s Ames Research Center and the paper was published in the Proceedings of the National Academy of Sciences.

An atmosphere can act like a prism, separating light that passes through it into a spectrum of its components. The result of this spectrum provides information about the planetary body’s atmospheric composition, temperature, and structure, giving clues about its habitability. For exoplanets, this information is obtained as it transits its parent star. The light that goes through the atmosphere isn’t much different, but different enough to obtain meaningful information.

Titan’s atmosphere produces a haze just like an exoplanet, and it is strongest at sunset. The Cassini orbiter, which has been studying Saturn up close since 2004, has also gathered a considerable amount of information about Titan. By comparing information about Titan from when it produces the heaviest amount of haze versus when the haze is not as strong, scientists will be able to clarify findings and refine techniques used on exoplanets.

“Previously, it was unclear exactly how hazes were affecting observations of transiting exoplanets,” Robinson said in a press release. “So we turned to Titan, a hazy world in our own solar system that has been extensively studied by Cassini.”

The heavy haze created by Titan, and presumably many exoplanets as well, may overcomplicate some of the spectral information collected by researchers. However, many models currently used by astronomers tend to err on the side of being overly simplified due to constraints of computing power. For this study, the researchers analyzed four instances of Titan’s haze, using Cassini’s visual and infrared mapping spectrometer instrument. 

They found that the haze makes it very difficult to collect information about anything beyond the uppermost layer of the atmosphere. Titan’s lack of gravity (when compared to Earth) allows its atmosphere to extend out about 600 km (370 miles) around it. However, the haze only allows instruments to detect the upper 150-300 km (90-190 miles). This prohibits scientists from gathering information about the lower parts of the atmosphere, which is more dense and has complex attributes.

“People had dreamed up rules for how planets would behave when seen in transit, but Titan didn’t get the memo,” said co-author Mark Marley. “It looks nothing like some of the previous suggestions, and it’s because of the haze.”

The team also found that the haze was more likely to block out blue light, which has a shorter wavelength. This could have considerable implications for previous analyses of exoplanets, as current models are based on the assumption that all wavelengths in the visible spectrum would be equally affected. 

The technique used on Titan could also be applied to Mars and Saturn. Using the information gathered from within our own solar system in the search for exoplanets greatly extends the usefulness of the orbiters and will allow scientists to gather more information about other worlds in the Universe.

Read more: http://www.iflscience.com/space/titan%E2%80%99s-sunsets-give-insight-hazy-atmospheres-exoplanets

Astronomers Determine Saturn’s Location With Astounding Accuracy

By combining signals from NASA’s Cassini spacecraft with observations from the National Radio Astronomy Observatory’s (NRAO) very long baseline array (VLBA), scientists have been able to accurately identify Saturn’s position to within a single mile. This information will be useful in understanding the orbits of planets in the outer solar system, and will have other widespread implications for future research. The study was led by Dayton Jones of Jet Propulsion Laboratory, and the paper was published in The Astronomical Journal. The work was also presented this week at the 225th meeting of the American Astronomical Meeting.

“This work is a great step toward tying together our understanding of the orbits of the outer planets of our solar system and those of the inner planets,” Jones said in a press release.

The VLBA is a network of ten radio antennae that span across North America, from Hawaii to the Virgin Islands. Working in concert, the array is able to resolve incredible detail across great distances. In this case, it was able to very accurately track the radio signal from the Cassini spacecraft, which has been orbiting Saturn for the last ten years. 

Using five years’ worth of Cassini’s signaling data, the VLBA was able to resolve Saturn’s location to an area smaller than two miles, which is roughly 50-100 times more accurate than previous calculations. This greatly clarifies Saturn’s ephemeris, which is the table that states a celestial body’s predicted location at any given point in time. 

“An accurate ephemeris is one of the basic tools of astronomy, and this work is a great step toward tying together our understanding of the orbits of the outer planets and those of the inner planets,” Jones explained to the NRAO. “The orbits of the inner planets are well tied together, but those of the outer planets, including Saturn, have not been tied as well to each other or to those of the inner planets.”

By better understanding Saturn’s orbit and where it will be at a given time in relation to other objects, astronomers can take advantage of research opportunities. These include using distant light to study its rings, the better timing of experiments with pulsars, and even improving tests regarding Einstein’s theory of general relativity using quasars. The updated ephemeris will also be quite useful for better navigation of spacecrafts, and has already improved the course of Cassini’s mission to make more meaningful measurements and observations.

The researchers hope to replicate the success from this study in the future with Jupiter. The VLBA will track the radio signals from NASA’s Juno spacecraft, which is set to insert into Jupiter’s orbit in July of 2016. As Jupiter and Saturn are the two largest planets in our solar system, having accurate ephemerides for these planets will be a tremendous accomplishment and greatly improve future scientific research and spacecraft missions.

Read more: http://www.iflscience.com/space/astronomers-determine-saturn-s-location-astounding-accuracy