Why is Titan of Saturn more focused

Saturn - portrait of an Adonis

Saturn, the second largest and most visually beautiful planet in the solar system, is different from the others

The gas giant Saturn cannot come up with any noteworthy superlatives. It is neither the largest nor the smallest, and with an average distance of 1,426,725,400 kilometers, neither is it the closest or most distant planet in the solar system. On the other hand, it is neither the closest nor the furthest from the sun, nor is it even the only ring planet of the solar system. Nevertheless, the distant celestial body can book a lonely record for itself, as it is without a doubt the most beautiful and aesthetic body of its kind among the star satellites in the solar system. No wonder that it is one of the most frequently targeted celestial bodies in astronomy. Thanks to the NASA orbiter Cassini, it is even one of those planets that planetary researchers currently know the most about.

Strong radioactivity and X-rays permeate and penetrate the planet ceaselessly. Enormous gravitational forces pull and tear at all forms of matter. Meteors, comets and other astral vagabonds succumb to the force of gravity and incessantly hit a plasma-like underground without forming craters. Hurricanes of tremendous speed the size of the Australian continent occasionally lash through the atmosphere. Violent lightning bolts discharge at regular irregularities. Life-threatening ammonia gases and clouds persistently vaporize over a liquid-gaseous "surface" that does not deserve this name. Because there is no clear boundary between atmosphere and surface on this rockless world.

Life on Saturn?

According to the American astrophysicist and popular author Carl Sagan, who died in 1996, the fact that Saturn, the sixth and second largest planet in the solar system, is really not a place to live on does not necessarily mean that the gas planet is completely hostile to life. Although even the most resistant terrestrial microbes would not have the slightest chance of survival on its 1400 degrees Celsius hot surface, highly bizarre creatures could have found an exo-ecological niche in the higher regions of the ring planet. "One way to live under the conditions described would be to reproduce before you are grilled and to hope that some offspring will be carried up to higher and cooler layers of the atmosphere by convection," Sagan suspected 30 years ago.

Today, 30 years later, since no astronomer seriously believes in potential life forms on Saturn, their interest is rather focused on the measurable characteristics of this distant world - and the true nature of the fascinating ring system. After all, Saturn is still as noble and graceful as it was 350 years ago, when the Dutch astronomer Christiaan Huygens (1629-1695) was able to dissolve and admire the aesthetic beauty of Saturn's rings for the first time through the eyepiece of his telescope.

Saturn's first artificial satellite

Since then, the planetary Adonis has been one of the most frequently targeted celestial bodies in astronomy. “The rings of Saturn are a symbol for all the exotic and amazing objects in the cosmos. The more precise the observations, the more their magic has increased, ”emphasizes US astronomer Joseph A. Burns from Cornell University in Ithaca (New York). Interest in Saturn and its satellites has skyrocketed in recent years. With good reason. The fact that until recently a whole armada of earth-based observatories and space observatories carefully targeted the ring planet and its "surroundings" happened in preparation for the most expensive and complex enterprise in the history of unmanned space travel: the NASA-ESA mission "Cassini-Huygens".

"Cassini-Huygens" won in 1982, inspired by the great successes of the previous probes Pioneer 11, Voyager 1 and Voyager 2, which passed Saturn and some of its moons from a great distance 25 years ago and transmitted fascinating data to Earth first contours on the drawing board. In the meantime, the double probe, which was the first artificial satellite to move into the orbit of the gas giant since the middle of last year, has dramatically increased our knowledge of the same and has given us color images of the highest quality.

Dynamic miniature planetary system

“The pictures are so beautiful - it's almost terrifying. I'm still not convinced that these images are real - they are so incredibly sharp, "enthused NASA researcher Carolyn C. Porco from the Space Science Institute (SSI) in the US state of Colorado / Boulder (USA) in July 2004 shortly after the first Saturn recordings were published. In fact, the images with a resolution of up to 150 meters per pixel are unrivaled in terms of sharpness.

No other telescope, no other space probe has so far provided more precise data and at the same time revolutionized the common image of the ring planet and its moons so radically. Ultimately, Saturn presents itself on the profile that the astro detectives created on site with their high-tech magnifying glasses and space scouts as even more dynamic than previously assumed. Surrounded by as many as 46 moons (so far discovered), the gas giant, consisting primarily of hydrogen and helium, is itself trapped in a very active, dynamic miniature planetary system. The moons of Saturn move their orbits along its finely structured ring system and keep each other and the countless ring particles - following a complicated gravitational interplay - in check. It is above all the shepherd moons or shepherd moons such as Atlas, Prometheus or Pandora, which stabilize the rings of Saturn. The researchers are currently distinguishing six major main rings, which are designated by the letters A to F in the order in which they were discovered. They are of different widths and thicknesses and are in turn composed of hundreds of small, concentric rings. Saturn's moons float in, around and next to them.

Aesthetic natural work of art

As compact and stable as this planet-encompassing tire may appear - in truth, the aesthetic natural work of art embedded in the Saturn equatorial plane consists of myriads of dirty dust and ice particles. They are millimeters to a few meters in diameter, in some cases even the size of a house. The main rings are predominantly composed of water ice, and molecular oxygen ions have also been detected in them: Hydrogen and oxygen atoms are distributed in different intensities in the planetary system that extends millions of kilometers beyond Saturn. "One possible explanation for this is that small, previously undetected ice moons collided with Saturn's E-ring," says Professor Larry Esposito from the University of Colorado / Boulder (USA). "The collisions may have produced tiny ice grains that produced oxygen atoms."

Saturn's ring particles may have been formed from pure ice, according to Esposito. But they have since been exposed to constant bombardment from meteorites, which contaminated the ice and thereby darkened the rings. "The evidence suggests that new material has likely been added to the ring system in the last ten to 100 million years." Remarkably, the Saturnian ring system is only a few hundred meters thick on average, at the thinnest points even less than 100 meters, whereas the diameter of the ring system is around 350,000 kilometers.

It would have space for 764 globes

“We don't know exactly how old the rings are. But most experts estimate that the rings are no more than a few hundred million years old, ”explains Carolyn Porco. The fact is: Saturn's dust bands are constantly losing material, although it is not yet clear whether they will one day completely dissolve or shimmer just as faintly as the small, thin, delicate rings that surround the other gas planets Jupiter, Uranus and Neptune.

While some of Saturn's moons orbit the gas giant once in just a few days, Saturn orbits its home star, the sun, at an average distance of 1.43 billion kilometers only once in just under 29.5 years. Although the ring planet with a diameter of 120,536 kilometers at the equator and 108,728 kilometers at the poles is the most flattened planet as a result of its unusual rotation and could easily accommodate 764 globes, it is the star satellite with the lowest density in the solar system. While its mass is just 95 times that of Earth, its density is only 0.69 grams per cubic centimeter. Even water has a higher density. Saturn's axis of rotation is also unusual: compared to Earth (23 degrees), it is inclined by 26 degrees, giving the gas giant even more intense seasons.

Mysterious magnetic field

No wonder that the equatorial regions of Saturn are among the stormiest in the solar system. Dense clouds, strong lightning, violent storms, especially wind speeds of up to 1400 kilometers per hour, are not uncommon here and are related to the rapid rotation of the planet. Because a single day on Saturn only lasts 10 hours and 39 minutes. Instead of emitting less energy than all other planets receive from the sun, a previously unknown heat source enclosed inside the gas giant emits almost twice as much energy (as received from the sun). Planetary researchers are still puzzling over whether the core of molten rock believed to be inside the planet at an estimated 12,000 degrees Celsius favors this process. The magnetic field on Saturn, which protrudes up to 500,000 kilometers into space and is 1000 times stronger than that of Earth, is also mysterious. On the one hand, the magnetic field rotates around the same axis as the planet itself, which physically should actually be the opposite.

On the other hand, the rotation speed of the magnetic field results in other times of revolution of Saturn. According to the scientists, the source of this strong magnetic field could be metallic hydrogen inside the planet. “The magnetosphere of Saturn is unique. Their dynamics are similar to those of Jupiter, ”summarizes Cassini specialist Dr. David Young, Head of Research at the Southwest Research Institute (SwRI) in San Antonio, Texas (USA).

Moon with a thin water vapor atmosphere

The previous fly-bys of the Cassini orbiter of some of Saturn's moons were also spectacular. To the surprise of the researchers, the probe was able to detect not only a thin water vapor atmosphere, but also fine dust particles on the 500-kilometer ice moon Enceladus. It is also unusual that Enceladus reflects almost 100 percent of the light falling on it. Even the 116-kilometer Saturn moon Epimetheus presented itself as a very irregularly shaped, crater-strewn moon during the Cassini flyby. The many large, rounded funnels suggest that the surface of the water ice moon is several billion years old.

The highlight of the entire mission nonetheless occurred on January 14, 2005, when the ESA probe Huygens landed on the largest and most mysterious moon in the Saturn system, Titan. The bits and bytes that the ESA landing vehicle radioed to earth during its almost four-hour operational phase speak for a geologically active satellite. "The images show complicated structures on the surface that indicate wind action, tectonic processes and river courses. They also show some circular shapes that could be impact craters," explains Porco.

Life on titan?

According to the researchers, there is nothing to indicate the presence of life on Titan for the time being, as Saturn's moon is today in a state that is similar to that of the primordial Earth 4.6 billion years ago. A strange world on which yellow clouds and black, oily methane lakes exist. Nonetheless, according to some exobiologists, this could be an ideal place to look for life. Since temperatures of up to minus 180 degrees Celsius close to the ground prevail on Titan, the moon cannot preserve liquid water, but theoretically life could thrive here in liquid hydrocarbons, which are obviously abundant on Titan. In any case, hydrocarbon solutions are in many ways even more suitable than water for controlling complex organic chemistry, some astrobiologists suspect. Life could exist in far more exotic conditions, such as the dense atmospheres of the large gas planets. Perhaps in the form of microbes that drift in the liquid ammonia clouds of Saturn or Jupiter. Without water, without carbon, perhaps with silicon as the basic building block.

Perhaps Carl Sagan is also right, who already suspected in the early 1980s that a layer of organic material that is more than 100 meters thick could have formed on titanium. A chemical and biological development could possibly have started here - like four billion years ago on Earth. "In view of the abundance of organic substances and sunlight, the possibility of life on titanium cannot be ruled out without further ado."

Literature tip: Lorenzen, Dirk H .: Mission: Saturn. Cassini reveals the secrets of the ring planet, Kosmos-Verlag, Stuttgart 2005 (Harald fence)

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