Tag Archives: Saturn

Hubble’s latest pic of Saturn is a pretty good one

The notion of a picture being worth a thousand words can often be an understatement. Witness the newest, just-released photo of Saturn captured by the Hubble Space Telescope.

Saturn by Hubble
The NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 observed Saturn on 20 June 2019 as the planet made its closest approach to Earth this year, at approximately 1.36 billion kilometers (845 million miles) away. (Photo: NASA, ESA, A. Simon (Goddard Space Flight Center), and M.H. Wong (University of California, Berkeley))

This image is the second in a yearly series of snapshots taken as part of the Outer Planets Atmospheres Legacy (OPAL) project, according to news releases from the European Space Agency and the Space Telescope Science Institute. OPAL is helping scientists to understand the atmospheric dynamics and evolution of our Solar System’s gas giant planets. In Saturn’s case, astronomers will be able to track shifting weather patterns and other changes to identify trends.


Please support Seattle Astronomy with a subscription through Patreon.

Enceladus and the platinum age of planetary exploration

Ours is a great time to be alive if you have an interest in learning about other worlds, at least according to Ron Hobbs, a NASA Solar System Ambassador and museum educator and public programs assistant at Seattle’s Museum of Flight.

“For most of us the golden age of planetary exploration was the ‘70s and early ‘80s,” Hobbs said. “The time of the Apollo Moon missions—particularly those that did a lot of science—the Viking missions to Mars, and of course Voyager.”


At least four distinct plumes of water ice spew out from the south polar region of Saturn's moon Enceladus in this dramatically illuminated image, shot on Christmas Day 2009 by Cassini. Light reflected off Saturn is illuminating the surface of the moon while the Sun, almost directly behind Enceladus, is backlighting the plumes. Photo: NASA/JPL/Space Science Institute.

After that, things slowed down a lot, but in recent years there’s been something of a renaissance in the solar system.

“The first decade of the 21st Century has been as good as, if not better than, the golden age,” Hobbs believes. “Some people have called it the platinum age of planetary exploration. And if there’s a flagship of that platinum age of planetary exploration it’s got to be the Cassini-Huygens spacecraft.”

Hobbs gave a talk about Cassini, titled “Seven Years in the Saturn System,” last month at the museum. The presentation featured lots of the spectacular photography from the mission, including the discovery of seasonal colors on the second-largest planet in the solar system. Hobbs also discussed discoveries about Saturn’s rings and the intense study of the huge moon Titan. But the most fascinating part of the talk centered on the moon Enceladus, which Hobbs says has joined the astrobiologists’ short list, along with Mars and Europa, for further study.

That’s largely because of the discovery of enormous geysers at the south pole of Enceladus, which spew out ice crystals that form Saturn’s E-ring and cover Enceladus with fresh snow, making it one of the brightest objects in the solar system. The interesting thing about the E-ring is that it contains salt.

“The salt had to come from somewhere,” Hobbs explained, “so somewhere down in Enceladus there must be water in association with hot rocks. So you’ve got an energy source, you’ve got water. We don’t know yet, but maybe we have organic chemicals. If we do, this becomes one of the likeliest places we could find life in the solar system.

“Enceladus has rapidly become one of the most important bodies for us to study,” he added.

Cassini’s work in the Saturn system is planned to continue until the summer of 2017, when it will make a handful of spectacular proximal orbits very close to Saturn’s cloud tops before it runs out of fuel and is crashed into the ringed planet.

That’s presuming Cassini keeps working. Hobbs notes that while the warranty has long since expired, the school bus-sized craft hasn’t missed a beat since it was launched in 1997.

“Space is a harsh environment, particularly when you go a billion miles from the Sun,” Hobbs noted. “It gets cold out there, and every time you go into the shadow of Saturn or one of the moons, it drops dramatically. So given our experience with technical things, it is kind of a surprise” that Cassini is still functioning, he said. “On the other hand, we in America seem to be building some really good stuff these days.”

It will be fascinating to see what wonders Cassini finds before the mission ends five years from September.


Storm on Saturn, and a Voorwerp

There are a couple of great new posts up on Alice’s Astro Info by Alice Enevoldsen this week.

The first, Storm on Saturn—With a Tail, was posted Sunday. It’s a great summary of a new storm that turned up on Saturn at the end of 2010. It’s about the same size as the Great Red Spot on Jupiter.

Storm on Saturn

Cassini captured this photo of the storm on Saturn on Christmas Eve, 2010. Photo: NASA/JPL/Space Science Institute.

We tried to spot this storm from Seattle Astronomy headquarters in West Seattle during that rare, clear weather we had over the holidays. Alas, while we had a couple of good looks at Saturn, it was still pretty low in the sky, a bit murky, and we couldn’t make out enough detail to spot the storm. (St. Nick delivered a new Tele Vue 10mm Radian eyepiece we were hoping would help tease it out, but even great new optics didn’t get us there.) Even today Saturn isn’t rising until a little after midnight. It’s plenty high before sunrise, but we’re a lot better at staying up until 3 a.m. than we are at rising at 5:00, so we haven’t seen the ringed planet at its best, and probably won’t until it’s at opposition in early April.

We’re rolling the dice by waiting to try to see this storm. While the Red Spot has been around for centuries, this Saturn storm popped up out of nowhere and could fade back into the yellow-orange haze of Saturn just as quickly.

The other new article, posted today, is about Hanny’s Voorwerp. It looks kind of like an enormous cosmic frog in an amazing Hubble photograph included in the post, but in actual fact is a light echo. Enevoldsen is a physics and astronomy genius and explains the phenomenon very well. I just think it looks cool. And I like to type the word Voorwerp. Voorwerp, voorwerp, voorwerp. It’s Dutch for “object,” and Hanny’s Voorwerp was discovered by a Dutch schoolteacher using Galaxy Zoo.

Keep an eye on Alice’s Astro Info for great notes about what’s up in the sky.