Category: cassini

Happy 230th Birthday, Enceladus, Our Solar S…

Happy 230th Birthday, Enceladus, Our Solar System’s Greatest Hope For Life Beyond Earth

“It is still a complete unknown whether Earth is the only world in the Solar System to house any form of life: past or present. Venus and Mars may have been Earth-like for a billion years or more, and life could have arisen there early on. Frozen worlds with subsurface oceans, like Enceladus, Europa, Triton or Pluto, are completely different from Earth’s present environment, but have the same raw ingredients that could potentially lead to life as well.

Are water, energy, and the right molecules all we need for life to arise? Finding even the most basic organisms (or even the precursor components of organisms) anyplace else in the Universe would lead to a scientific revolution. A single discovered cell in the geysers of Enceladus would be the most momentous discovery of the 21st century. With the recent demise of Cassini, on the 230th anniversary of Enceladus’ discovery, the possibility of finding the incredible compels us to go back. May we be bold enough to make it so.”

On this date in 1789, William Herschel, armed with the most powerful telescope known to humanity at the time (you can get a lot of grant money when you discover the planet Uranus and name it after the King), discovered a relatively small moon of Saturn just 500 kilometers across: Enceladus. For some 200 years, Enceladus was never seen as more than a single pixel across, until the Voyager probes flew by it. What they revealed was a remarkable, unique world in all the Solar System. Now that the Cassini mission is complete, we can look back at all we know about this world, and all the signs point to a remarkable story: there’s a subsurface ocean, possibly suitable as a home for undersea life.

Is Enceladus truly our Solar System’s best hope for life beyond Earth? That’s debatable, but there’s every reason to be hopeful. Come get the story here.

Saturn, Not Earth Or Jupiter, Has The Largest …

Saturn, Not Earth Or Jupiter, Has The Largest Storms In Our Solar System

“But from December of 2010 to August of 2011, the largest storm of all occurred: on Saturn. For 200+ days, this Saturnian hurricane raged, maintaining its leading “head” until May. It came to encircle the entire planet, as methane-poor tail end stands out against the relatively methane-rich remainder. Viewed 11 hours (1 Saturn-day) apart, we determined the hurricane migrated across Saturn at 60 miles-per-hour (100 kph). These storms have occurred every 20-30 years since first observed in 1876, as hot air rises, cools and falls.”

Many worlds in our Solar System have enormous storms that occur in their atmospheres. Earth routinely experiences hurricanes, with wind speeds frequently in excess of 225 kph. But what happens on the giant worlds in our Solar System dwarf anything that happens on Earth. Saturn’s hurricane at its north pole is bigger and faster than any hurricane we’ve ever seen here. Jupiter’s great red spot is bigger than the entire Earth itself. But the largest storm of all? 

Believe it or not, it’s a periodic weather event that appears to occur on Saturn every 20-30 years or so. Keep your eyes peeled in the 2030s, because it’s going to return!

astronomyblog: Images taken by the Cassini & Voyager…

astronomyblog:

Images taken by the Cassini & Voyager spacecraft of Titan, Saturn’s largest moon. Titan is the only moon in the Solar System to have a thick atmosphere and lakes of hydrocarbons (methane and liquid ethane).

To know more about the moon Titan click here

Image credit: NASA/JPL/SSI/Cassini & Voyager ( precessed by: Kevin Gill )

Top 6 Discoveries Of Cassini As Its 20-Year Mission Comes To An…

Top 6 Discoveries Of Cassini As Its 20-Year Mission Comes To An End

2.) The largest storm ever known in the Solar System. Like all the planets with atmospheres, Saturn contains its own weather, complete with storms both large and small. While the Cassini mission was able to discover a number of interesting ones on the ringed-world, such as the long-lived polar hexagon and the Southern hemisphere’s Dragon Storm, the most spectacular occurred in 2011, emerging in the northern hemisphere, encircling the entire planet, lapping itself and lasting over 200 days. Images taken as close together as one rotation apart showed that the storm migrated across the Saturnian surface at 60 miles per hour (100 km/hr).

While a handful of storms of this magnitude have been observed every 20–30 years or so dating back to 1876, this was the largest, longest-lived one. In April, we found these storms are suppressed by water vapor in the lower layers of Saturn’s atmosphere. Being heavier than not only hydrogen and helium but also methane, the wet water vapor forms a layer underneath Saturn’s outer exosphere, insulating the inner part of the world. Eventually, the outer layers cool so much that they sink, allowing the inner, wet layers — and storms — to re-emerge. Having developed this picture from Cassini’s true and false-color images, the next major Saturnian storm, predicted for the 2030s, could finally teach us how much water our ringed neighbor contains.”

Launched back in October of 1997, Cassini will take its final plunge into the ringed world it’s been orbiting for over a decade on Friday, September 15th. Before it does, however, it’s worth a look back at the tremendous science that’s come about from the first dedicated mission to venture out to Saturn, including a series of surprises that we had no idea we’d find when we were planning and preparing this mission. Sure, our radioisotope-powered spacecraft was equipped with a lander to investigate the giant moon Titan, and many instruments to analyze the various molecules it would find on Saturn, in its rings, and in its many moons. But the polar hexagon and the central vortex, the largest storm ever seen in the Solar System’s history, a myriad of features in the rings (and their gaps), the cause of the two-toned nature of Iapetus and much, much more all came about not because we were seeking to solve these mysteries, but because we had built a spacecraft capable of looking for more than what we were anticipating.

Take a look back at the top six discoveries of Cassini, with more than 20 images to take your breath away!