Archiv für Saturn

Organic Chemicals in Titan's High Atmosphere

Since the twin Voyager spacecraft flew past Saturn’s moon Titan, scientists have been excited about what its hazy atmosphere can tell us about the earliest days of our own planet. The Voyagers discovered that Titan’s atmosphere is swirling with hydrocarbons and other complex organic molecules that could be the building blocks of life. The latest findings from NASA’s Cassini spacecraft have uncovered that these organic molecules are floating higher in Titan’s atmosphere than scientists originally thought. The latest research, published in the May 11 edition of the journal “Science”, shows that these organic aerosols, called tholins, have been found in altitudes higher than 1.000 kilometres above the surface of Titan. This is important because Titan’s environment is thought to be very similar to Earth’s early history, before the first life formed. A similar process could have happened here.
Hunter Waite et al.: “The Process of Tholin Formation in Titan’s Upper Atmosphere”

Graphic: Tholin Formation

Jupiter As Seen From Saturn

It’s not a great picture of Jupiter, but that’s not the point. The point is that this photograph was taken by NASA’s Cassini spacecraft currently orbiting Saturn. When the picture was taken, Cassini was approximately 1.8 billion kilometres from Jupiter. So, at the time of the photograph, the distance from Saturn to Jupiter was roughly the same as the distance from the Earth to Saturn. A similar picture of Earth would only light up a single pixel in Cassini’s camera.


Moon affects Saturn's rotation period

Because Saturn doesn’t have a visible surface, scientists have used the rotation period of the planet’s magnetic field to measure the planet’s rotation, a technique used successfully for other gas giants. In a paper published in last week’s issue of “Science”, researchers said that geysers erupting from Saturn’s moon Enceladus eject water vapor and ice that interact with the planet’s magnetic field, weighing down the field and making the planet to appear to rotate more slowly. This effect may explain past observed changes in the planet’s rotation period.
Enceladus Geysers Mask the Length of Saturn’s Day

Cassini radar shows evidence of seas on Titan

Instruments on NASA’s Cassini spacecraft have found evidence for seas, likely filled with liquid methane or ethane, in the high northern latitudes of Saturn’s moon Titan. One such feature is larger than any of the Great Lakes of North America and is about the same size as several seas on Earth.


Radioactive Core Might Explain Geysers on Enceladus

Since Cassini arrived at Saturn, it has made many impressive discoveries. One of the most intriguing is the discovery that Saturn’s icy moon Enceladus has geysers spewing water ice into space. Some planetary scientists theorize that there are pockets of liquid water near the surface of Enceladus that could harbour life. But where is the heat coming from to fuel these geysers? A new model proposes that the rapid decay of radioactive elements might be keeping the moon hotter than it would normally be. This heat is released through cracks in the moon’s surface, and since Enceladus is covered with ice, it has water geysers. The theory says that Enceladus started out as a ball of ice and rock, with rapidly decaying isotopes of aluminum and iron. Over the course of just a few million years, this decay produced a tremendous amount of heat, creating a rocky core and a surrounding shell of ice. The moon then slowly cooled over the course of billions of more years. The theory matches some of the elements seen in Enceladus’ geysers, such as gaseous nitrogen, methane, carbon dioxide, propane and acetylene. These could come from the decomposition of ammonia deep inside the moon where the warm core and water meet.
A Hot Start Might Explain Geysers on Enceladus

Huygens landing site to be named after Hubert Curien

As of March 14, 2007, an epic space mission and one of the founding fathers of the European space endeavour will be forever linked. ESA, the international Committee for Space Research (COSPAR) and NASA have decided to honour Professor Hubert Curien’s contribution to the European space endeavour by naming the Huygens landing site on Saturn’s largest moon Titan after him. The naming ceremony for the Huygens landing site, which will be known as the “Hubert Curien Memorial Station”, will be held at ESA’s Headquarters on March 14, 2007, in the presence of ESA Council delegates and of Professor Curien’s wife, Mrs Perrine Curien, and one of their sons. Huygens’ landing on Saturn’s largest moon in January 2005 represented one of the greatest successes achieved by ESA. This was made possible thanks to the commitment of a man who, for several decades, worked to promote and strengthen the role of scientific research in his home country France, and in Europe.
Source: ESA
Wikipedia: Hubert Curien

Unique New Perspectives of Saturn

Flying in a polar orbit around Saturn for the last two months, NASA’s Cassini spacecraft is now sending back completely unique images of Saturn, seen from overhead.

Large Lake Surrounds an Island on Titan

NASA’s Cassini spacecraft has been turning up new images of features that look like lakes on the surface of Saturn’s moon Titan. The latest image shows a large lake that appears to be surrounding an island. Unlike the familar lakes here on Earth, this lake is likely filled with liquid hydrocarbons.

Saturn moon sprays neighbors with ice

A Saturnian moon with active geysers is coating a number of other moons with ice particles. In a paper published in the journal “Science”, researchers found that ice geysers on the moon Enceladus had ejected ice particles that were coating the surfaces of at least 11 other moons of Saturn. That coating of ice particles explains why those small moons, which are themselves not geologically active, have bright surfaces that must be renewed regularly to remain highly reflective. Enceladus and the other moons all orbit in Saturn’s E-ring, which itself is formed by ice particles from Enceladus.
University of Virginia Press Release

Tour de Saturn Set For Extended Play

The Cassini spacecraft is now two and half years through its official “primary tour” of the Saturn system which is scheduled to last another 17 months before ending on June 30, 2008. During this primary tour Cassini will have made 46 close flybys of Titan (during one of which it dropped off the successful European Space Agency’s Huygens Titan lander), four close flybys of the unexpectedly fascinating moon Enceladus, and one each of Tethys, Dione, Rhea, Hyperion, Iapetus and Phoebe. On the basis of what is done so far Cassini must be considered a scientific and space art spectacular. It has revealed major new mysteries about Titan and Enceladus which have a direct relevance to the possibility that one or both moons have evolved microscopic life. Moreover, Cassini has apparently solved at least two of the biggest scientific mysteries about the Saturn system: the mysterious longevity of its ring system, and the remarkable difference between Iapetus’ black leading side and its bright whitish trailing side. Later this year in September, having completed most of the planned flybys of Saturn’s smaller moons, Cassini will make its one close flyby of the distant and hard-to-reach moon Iapetus. Coming within 1.500 km it will be able to make its best observations of Iapetus and hopefully solve the remaining puzzles about it. The following March in 2008 Cassini will make its closest flyby of Enceladus skimming a mere 23 km above the geyser-like water and ice plumes which are erupting from the south polar region. Scientists working with Cassini are looking at how an extended mission would work. From the time Cassini first entered orbit around Saturn, they have been working on the design of a possible extended tour, re-planning it on the basis of the craft’s new discoveries about the Saturn system.
Cassini Equinox Mission

CICLOPS Public Website

ESA – Cassini-Huygens