Bonus Post - The Moons of Saturn

Credit: Cassini Imaging Team/SSI/JPL/ESA/NASA

Like Jupiter, Saturn has many moons, and the Cassini space craft sent back some remarkable data, including images, of some of the Saturian satellites. Above is Tethys, an ice moon, with Saturn providing a magnificent backdrop.

Credit: Cassini Imaging Team/SSI/JPL/ESA/NASA

Here's a close-up of Tethys's surface. While Tethys is composed almost entirely of water ice, scientists think it was mostly liquid water at some point in the past.

Credit: NASA/JPL/Space Science Institute

Hyperion is another ice moon, but its strange appearance is reminiscient of sea coral or a sea sponge ("Saturn's Loofah"). It's actually very porous, so debris that slams into Hyperion forms much deeper craters than if the same debris hit other moons.

Credit: Cassini Imaging Team/SSI/JPL/ESA/NASA

Enceladus is a geologically active ice moon, spewing ice particles and water vapor into space from the false-color blue "tiger stripes" seen above. This may mean there is liquid water just under the icy surface - an indication that Enceladus might harbor life.

Credit: NASA/JPL/Space Science Institute

Finally, we have Titan, above, a mysterious world with a hazy atmosphere made up of nitrogen and methane.

Credit: Cassini Radar Mapper/JPL/ESA/NASA

If the air doesn't sound appealing, consider this radar image of the surface, which seems to show a dark sea along with islands and a coastline. The sea may be composed of liquid hydrocarbons, another place where life could develop. Since there is also speculation that Titan has methane rain showers, it would have to be some pretty unusual life.

Credit: ESA/NASA/Descent Imager/Spectral Radiometer Team (LPL)

Part of the Cassini mission included deployment of the Huygens lander to Titan's surface. This true-color image from Huygens shows an eerie orange haze over a rocky surface. Things are looking a little more familiar here, until you think about the methane rain thing again.

That's just a brief overview of a few of Saturn's many moons. There's no need to venture into deep space to encounter cosmic strangeness - it's right in our own neighborhood. Icy, wet, methane-soaked moons circle the ringed planet for your consideration, just as they have for millenia.

The Night Sky's Wanderers - Saturn

Credit: CICLOPS/JPL/ESA/NASA

When I first learned about the planets in school, I remember deciding that Saturn was my favorite, because it had rings. We now know that Jupiter, Neptune and Uranus also have rings, but Saturn's are the most spectacular.

Humans have known about the rings of Saturn since the 17th century, but in the last few years, we've been able to see them from a new perspective. The image above was taken by the Cassini spacecraft from Saturn's orbit. It shows Saturn eclipsing the sun and seems to reveal that Saturn's night side receives some reflected light from its rings.

Credit: Cassini Imaging Team/SSI/JPL/ESA/NASA

In another perspective not visible from Earth, this Cassini image shows Saturn as a crescent. The light and shadow interplay here is impressive, with the rings casting shadows onto the planet surface, and the planet casting its own shadow onto the rings. Saturn, like Jupiter, is a gas giant, and subtle banding in its cloud tops can be seen here as well.

Credit: Cassini Imaging Team/SSI/JPL/ESA/NASA

This final "beauty shot" shows Saturn from below. The resolution of these images is spectacular, but Cassini had more in store for scientists - confirmation of a very strange formation at Saturn's north pole.

Credit: NASA/JPL/VIMS Team/University of Arizona

This Cassini infrared image confirms the hexagonal cloud system originally spotted by Voyager in the 1980s. It's not just a chance arrangement of clouds: this movie shows the rotation of the entire hexagon. Scientists are working on explanations for this phenomenon, but let's face it - this is beyond mysterious. It's more like, who could even conceive that something like this existed? How can clouds possibly form this shape?

As the late Carl Sagan said, "Somewhere, something incredible is waiting to be known."

Lullaby for Grown-Ups - Ella Fitzgerald

Time for some jazz, and what could be better than Ella singing that night-themed classic, 'Round Midnight? This performance is from the 1979 Montreux jazz festival. Lady Ella truly was amazing. I get chills when I listen to her sing the final notes. I hope you enjoy the timeless art of Ella and her trio.

Diversions for Insomniacs #4

It's time for another cool game. This one, Quest for the Rest, was actually created as a promotion for the band The Polyphonic Spree. Help the lost band members find their way through different environments as you enjoy songs from the Spree's album, Together We're Heavy. I like the ambience of this game - both the music and the visuals. It's a fine way to spend some time when sleep eludes you.

Lullaby for Grown-Ups - Manu Delago

Here's a video from a very talented hang drum player, Manu Delago. The hang drum was invented just eight years ago. The two Swiss inventors are also the only manufacturers and prospective buyers must journey to their workshop to place their order and pick up their instrument. I like the sound of it - less brash than a steel drum, allowing for more nuance. Relax and enjoy this week's lullaby!

Bonus Post - The Moons of Jupiter

Credit: Cassini Imaging Team/Cassini Project/NASA

Before we move past Jupiter, let's take a look at some of its orbiting bodies. Jupiter has more than 60 moons, but I'll confine this post to the four Galilean satellites, so named because Galileo discovered that they were not stars, but moons orbiting Jupiter.

Above we have Io casting its shadow against the Jovian clouds. The scale of Jupiter's size begins to become clear.

Credit: Cassini Imaging Team/Cassini Project/NASA

Here's Io again, in a breathtaking image that, like the one above, was taken by the Cassini spacecraft en route to Saturn. The clarity of this image is so startling that it conveys a sense of stillness. In fact, Io completes its orbit of Jupiter once every 42 hours. It's moving along at a very good clip.

Credit: Galileo Project/JPL/NASA

Io has more volcanic activity than any other body in the solar system. This true-color close-up image of Io shows its yellow surface, the result of high levels of sulfur and silicate rock.

Credit: Cassini Imaging Team/Cassini Project/NASA

Here is Jupiter and its largest moon, Ganymede, which is also the largest moon in the solar system. The Great Red Spot on Jupiter is visible to the right, almost as if Jupiter is looking at its moon.

Credit: Galileo Project/JPL/NASA

The surface of Ganymede is rocky, icy and cratered, characteristics it shares with its neighbor, Callisto (below).

Credit: Galileo Project/Voyager Project/JPL/NASA

Callisto is heavily cratered and its surface is thought to be four billion years old. Unlike Io, there is no geologic activity to drastically alter its surface, making it the oldest landscape in the solar system.

Credit: Galileo Project/JPL/NASA; reprocessed by Ted Stryk

Finally we come to Europa, with its strange surface that almost makes it look like a cosmic ball of twine. The bright areas are water ice, and this is the moon that scientists think may have oceans under its surface. The European Space Agency is planning to put a spacecraft into orbit around Europa to determine the thickness of the surface ice, with a long-range goal of using hydrobots to tunnel below the surface and search for life.

Here are some helpful hints to find the moons of Jupiter yourself. Ordinary binoculars will do the trick. Stay warm!

The Sounds of Jupiter

One aspect of NASA's planetary research we haven't touched on is their space sound recordings. This video features "sounds" from Jupiter recorded by special instrumentation aboard Voyager. Electromagnetic vibrations from solar winds and charged particles in Jupiter's magnetosphere were collected and converted to sounds within the range of human hearing.

What do you think of Jupiter's song? Is it eerie or soothing? Or both, somehow? I find it to be an dense, alien language, created by ancient and ongoing processes that are shrouded in mystery and exist beyond the scope of human activity or influence. But let's give credit to the Voyager team, whose ingenuity brought us this strange, otherworldly song.

For a complete list of NASA's space sound recordings, follow this link.

The Night Sky's Wanderers - Jupiter

Credit: NASA/JPL/Space Science Institute

Spectacular Jupiter, largest planet in the solar system, is as mysterious as it is beautiful. Classified as a gas giant, all we can see of it are its cloudtops. These swirling, exotic clouds are made up of ammonia, hydrogen sulfide and water and are capable of generating lightning.

Credit: Cassini Imaging Team/Cassini Project/NASA

One of Jupiter's most distinctive features, the Great Red Spot, is a giant storm that has been raging since at least the 17th century, when it was first observed by humans.

Credit: Voyager 2/NASA

Jupiter may have a rocky core; we don't know for sure. But most of its bulk comes from liquid metallic hydrogen - a form of hydrogen that only exists under extreme pressure.

Jupiter's rings were discovered during the Voyager 1 flyby in 1979. Apparently, two of the scientists on the Voyager team insisted that they look for rings, even though no one thought they would find any. And there they were. (The image below was taken by the Galileo spacecraft.)

Credit: NOAO/J. Burns (Cornell) et al./Galileo Project/JPL/NASA

I could go on with more facts about Jupiter, but let's face it - these planetary posts are really about the images. It can be hard to keep track of the news about the various spacecraft and each new set of dazzling images. By the time we finish with this tour of the solar system, you should be all caught up (at least for a little while!).

Lullaby for Grown-Ups - Josh Rouse

Here's a mellow song, Quiet Town, from Josh Rouse. Who wouldn't want to spend some time in this lovely seaside town? I'll just have to imagine myself there as I relax to this week's lullaby.

The Night Sky's Wanderers - Mars

Credit: J. Bell (Cornell U.), M. Wolff (SSI) et al., STScI, NASA

Mars, the angry red planet named for the Roman god of war, has long been a planetary candidate to shelter extraterrestrial life. From the 19th century observation of canals (which turned out to be an optical illusion) to the mid-20th century War of the Worlds radio broadcast of invading Martians to recent images of faces and creatures in the rocky landscape, there is something about Mars that has given humans hope that we are not the sole occupants of our solar system.

Credit: Mars Exploration Rover Mission, Cornell, JPL, NASA

Images of the Martian surface are coming back from NASA's Exploration Rovers and the European Space Agency's Mars Express. What's interesting about these images is that it's not at all hard to imagine walking around in this landscape. Dusty and rocky, it brings to mind a desert - not so different from Earth.

Credit: Mars Exploration Rover Mission, Cornell, JPL, NASA

The image above not only shows sandy dunes, but clouds in the Martian sky. It might be easy to imagine walking around, but you better bring your own air. The atmosphere is almost all carbon dioxide. Clouds can be composed of carbon dioxide ice or water ice.

Credit: G. Neukum (FU Berlin) et al., Mars Express, DLR, ESA

While there is no liquid water on Mars, there is water ice near the poles. This Mars Express image of a region near the north pole, taken from orbit, shows white areas of ice and steep cliffs almost 2 km (1.2 miles) high.

Back in August 2003, Mars passed as closely as it had to Earth in 60,000 years. I grabbed my binoculars to get a look. There it was, red and strangely large. It gave me an odd feeling to see it, something I've also felt when viewing a lunar eclipse. There was an uneasiness, almost a primal reaction to something unusual going on in the night sky. It was some vestige of an ancient response to natural phenomena that were uncommon and not well understood, the kind of response that no doubt led to some action to appease the gods.

To see more images of Mars, go to the Astronomy Picture of the Day link and search for Mars. You'll find pictures of a dust devil, a two-toned rock and other unusual features of the Martian surface.

"Mars is there, waiting to be reached." - Buzz Aldrin

Lullaby for Grown-Ups - Dead Can Dance

This week's lullaby, from videographer Sandra Egidio, features exquisite deep-space imagery paired with the music of Dead Can Dance. The song is Devorzhum.

The Night Sky's Wanderers - Venus

Credit: NASA/Johns Hopkins APL/Carnegie Institution

Beautiful Venus, the brightest object in the night sky after the moon, has been shrouded in mystery for millenia and has only recently begun to give up some of its secrets to science.

The atmosphere of Venus is filled with thick clouds that had kept scientists from viewing its surface. The image above from the Messenger spacecraft is typical of images of the planet taken using only visible light.

To overcome this problem, Venus has been imaged using radar and ultraviolet light. The image below, from the Magellan spacecraft, was created using radar and shows a false-color map of the planet surface, with red representing mountains and blue, valleys.

Credit: Magellan Spacecraft/Arecibo Radio Telescope/NASA

The only probes that have landed on Venus to date are the Soviet Venera 9 and 10 space crafts. They landed on Venus in October 1975 and sent back images, including these:


The Russian-made Venera probes were created to withstand the extraordinary atmospheric pressure on Venus (equal to 90 Earth atmospheres), extreme temperatures (around 850 degrees F) and a descent through the thick clouds in the upper atmosphere, which are made up of sulfuric acid.

Does that somehow sound familiar to you? A Russian-made probe designed for extreme conditions? It certainly sounded familiar to me, as a long-forgotten pop culture memory slowly made its way back to the light of day.

It was, in fact, the basis of a two-part episode of the The Six Million Dollar Man. "Death Probe" first aired in 1977 and featured a Russian probe that had been launched into space to study the surface of Venus. But somehow it returned to Earth and landed in the western U.S. Thinking it was on Venus, it began carrying out its mission, but when it encountered human resistance, it turned deadly. If it could withstand extreme pressures and temperature, how could it be stopped?


If you remember this episode, you also remember its strange yellow eye that zeroed in on any human standing in its way.


Creepy! But fortunately, Colonel Steve Austin was on the case and was finally able to destroy the formidable probe.

Portions of "Death Probe" are up on YouTube. People leaving comments vividly remember this episode, with some actually reporting nightmares. I had no idea it was based on actual space craft, but I also remember this episode very well. In many ways, it's emblematic of 1970s television - Russian bad guys, polyester clothing. But what really made it stand out was the idea of technology run amok. What humans had created could not be controlled and was now a deadly threat. Colonel Austin and his friends had to use both technology (his bionics) and their brainpower to bring an end to the rampage.

It was exciting viewing back then. To be honest, more than a few of my childhood evenings were spent in front of the television. But there were also trips to the planetarium and local observatory to get a first-hand look at the planets, unfiltered by thoughts of scary space probes.

If memories of action shows aren't enough of a planetary encounter for you, you're in luck. Check out the pre-dawn sky this weekend, where Venus and Jupiter will be in close proximity. You'll find them rising out of the east-southeast horizon a couple of hours before sunrise. Sunday morning, the crescent moon will join them to create a lovely show.