The probe “Cassini” starts the first in a series of 22 flights between Saturn’s rings and its atmosphere.
This will be the last mission of the probe to collect scientific data, which will end in September.
Cassini, moving with a speed of 110 thousand kilometers per hour, for the first time “dives” under Saturn’s rings at 9am GMT (noon GMT).
Due to the risk of collision with the particles of stone or ice, the probe will use its large antenna as a shield. At this speed a collision with even a tiny particle might prove to be absolutely disastrous for the spacecraft.
Analysts believe that the chances of such a collision is small, but the experts in mission control want to avoid even the smallest risk.
Since the antenna at the time of passage is not directed towards the Earth, radio contact with the probe on the time-of-flight will be lost.
The mission control center expects the contact with the probe will be restored only after 20 hours.
If the operation proves successful, then Cassini will make another 21 such passage in the next five months, after which the probe enters the dense layers of the atmosphere of Saturn. As on Board the “Cassini” by that time there won’t be enough fuel, his mission could not be continued.
NASA calls the spans between the atmosphere of Saturn and its rings with a Grand finale.
If there are no accidents, “Cassini” will be sent to Earth photographs of unprecedented quality, as well as data that will help to resolve many hitherto unresolved issues about the history of this planet.
“This mission will bring many new and surprising data,” said Atena of Custine of the Paris Observatory in MEUDON, France.
“We expect to obtain information about the composition, structure and dynamics of the atmosphere of Saturn, and also amazing information about the rings,” she says.
One of the main objectives of the mission to determine the mass, and, consequently, the age of Saturn’s rings. The more mass, the higher the chance that they exist from antiquity, perhaps even being the same age as the Saturn.
“In the past we could not determine the mass of the rings because Cassini flew away from them,” explains Luciano of Ies from the University of Rome La Sapienza.
“The influence of the rings on the gravitational field it was impossible to measure due to the oblate shape of Saturn. But by flying between the planet and its rings, Cassini will be able to determine the properties of space around the planet,” he adds.
“We are able to determine the speed of Cassini, up to several microns per second. It’s just amazing, if you remember that Cassini is at a distance of more than a billion kilometers from Earth”.
But, says Nicholas Altobelli from the European space Agency, even if scientists can determine the mass of the rings, it does not follow that they will be able to determine their age.
“We still need to understand the parameters of the composition of Saturn’s rings. They are composed of almost pure water ice. If their age corresponds to the age of the Saturn, why do they look so fresh when they are constantly bombarded by meteorites?”, he says.
According to one theory, the age of the rings can be quite small, as they may be the remains of a comet that came too close to Saturn and was torn its gravitational field into countless fragments.