The rings of Saturn appear to be significantly younger than, for a long time suspected. You are not created the same time as the planet around 4.5 billion years ago, but as recently as a few tens of to a hundred for a hundred million years. So at a time, as it was here on the earth dinosaurs (at least until their extinction 66 million years ago) and mammals. This is evident from the data, an international team of researchers led by Luciano Iess from the Sapienza University in Rome presenting now in the journal “Science”.
13 years to the Saturn spun
The scientists, based on measurements by the Nasa spacecraft Cassini, which has been exploring the planet for 13 years, before it crashed in September of 2017, as planned in the Interior. At first, they circled the planet in wide curves, but at the end of the Mission, the Orbits were changed so that Cassini between the innermost Ring and the planet’s surface through whistled. Meanwhile, measured the researchers, the gravity field of Saturn. It shows how, depending on the überflogener Region, the attraction will change, which again points to the mass distribution and thus on the internal structure of the planet in this area.
Mega-garbage chute. The rings of the sixth planet of the solar system are believed to be from the wreckage of a celestial body…photo: Nasa/JPL-Caltech/SSI
in Addition, the attraction and the mass of the inner rings are measured, which were, thanks to the narrow trajectory on the opposite side of the probe. For the gravity field measurement, the researchers used radio waves that were sent between stations on the earth, and Cassini. Simplified it works like this: Moving the probe at a constant speed in the direction of an antenna on the earth, compressing the emitted waves (in accordance with the Doppler effect). Fly Cassini to a particular mass region is over-rich, will change as a result of attraction of your speed, and thus the wavelength of the radio signals.
atmosphere of the planet is 9000 kilometers thick
From this data have calculated Iess and colleagues of the gravity field and its Variation. In complex computer models you have tested then on how the best way to explain. Accordingly, the different speed of rotation of the individual parts of the gas planets – the differential Rotation plays a crucial role. The values vary depending on the location on Saturn. Grossly simplified, it rotates within ten and a half hours once on its axis. In addition, the models show that the East-West-directed winds in the primarily of hydrogen and Helium existing atmosphere to 9000 kilometers deep, or around 15 percent of Saturn’s radius.
“This result is surprising and impressive,” said Elias Roussos from the Max-Planck-Institute for solar system research in Göttingen, Germany. He was part of a Team that researched by using a particle detector of Cassini, the magnetic field and its effects; in the current study, he is not involved. Roussos hopes the new findings, notes on the origin of the magnetic field. Curiously, the axis of which is almost perfectly parallel to the axis of rotation, in the case of any other planet in the solar system.
mass of Saturn’s rings indicates young history
in Addition have estimated to be Iess and his Team are the mass of Saturn’s rings, and thus an important clue to their age. “This is an exciting question that is discussed controversially for years,” says Roussos. The astronomers-bearing means, the ring system is the remnant of the original, proto-planetary dust disc, from 4.5 billion years ago Saturn. The other says the rings consist mainly of ice, dust and chunks of rock, had only emerged much later.
the age estimate, different methods are used, explain the Iess and colleagues in the article. This example based on changes in the edges of the individual rings or the decay rate of the smaller moons. Most of the methods suggest that rings with a low mass are younger, writes the Team. The current mass estimate of about 1.5 times 10 to the power 19 kg (15 million billion tons). That sounds like a lot, but yielded less than other estimates. The researchers argue, therefore, that the striking dust discs around Saturn are much younger than the Planet. They originated in front of a few tens to hundreds of millions of years and were initially perhaps somewhat massive than it is today. “This is convincing and makes it very likely that the age of the rings is actually rather low,” says Roussos.
in addition to Saturn, the other gas planets Jupiter, Uranus, and Neptune have rings. As a source for the small particles only smashed asteroids do not apply. Also the constant bombardment of the planet’s moons with cosmic Material creates dust that settles into fine rings, to the “mother planet”. And there is still a mechanism. The E-Ring of Saturn is primarily filled by the Material, the spit out the Eisvulkane on the moon Enceladus. Even Mars could one day get a Ring. Namely, when the moon Phobos comes so close that he is also torn apart by the tidal forces. Depending on the model bill, the 20 to 40 million could be done, maybe 70 million years ago.
origin of the rings – probably a moon or Asteroid
What exactly is the mighty rings of Saturn arise, say the authors. A common theory is that a larger moon or an Asteroid has come to the planet so close that tidal forces pulling on the front and back, to different degrees, have been getting stronger and stronger – until the chunks of tore up and the debris is distributed around the planet.
Actually, we would be pretty lucky to see the rings, because they are only temporary and disappear again, added the researchers in göttingen. “Fractional pieces that come too close, the planet will eventually fall down on him. And the heat resulting from the impact of micrometeorites, the particles also evaporate as the sun’s rays.“
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astronomy On Saturn it is raining rings
The loss is considerable. Already in 100 million years, the rings are likely to be gone, have recently attributed to researcher James O’Donoghue of the University of Leicester in the journal “Icarus”. Unless, one day, another big celestial body of the path, which is then pounded by the tide and materials for the new rings provides. “Theoretically, this is possible, but the probability is very low,” says Roussos. “There used to be, more often, large collisions, but now it’s pretty empty out there. The replenishment is missing.“
