The Cassini spacecraft burns on Saturn

The Cassini spacecraft has disintegrated today in the atmosphere of Saturn ending a 20-year mission in which it has contributed to unveil the secrets of the sixth planet of the Solar System like no other spacecraft has done.

The ship has burned shortly after entering the outermost layers of the thick gas envelope surrounding the planet. The spacecraft has used the little fuel left in its propellers to keep the antenna facing the Earth and transmit data until the last moment before losing control and disintegrate completely by the friction with the air. The  NASA has carefully planned this maneuver to avoid contaminating the planet 's moons, which can harbor life.

Flight engineers have followed the maneuver from the Jet Propulsion Center in Pasadena. The last signal of the ship has been received in the control center around 13:55 Spanish peninsular hour.

"This is the end of the mission," said Earl Maize, head of the Cassini Program. "I hope everyone is proud of this incredible success," he added before merging into a hug with one of his peers.

Our spacecraft has entered Saturn's atmosphere, and we have received its final transmission.

- CassiniSaturn (@CassiniSaturn) September 15, 2017

The Cassini-Huygens mission , a joint project of NASA and the European Space Agency launched in 1997, was the first to focus on exploring Saturn and its rings. Their discoveries were fundamental to prove that there can be life in other places of the Solar System and that these are not exactly similar to the Earth.

In 2005, the Huygens module became the first space artifact to land on a moon on another planet, Titan, where the mission discovered mountains, lakes and oceans filled with liquid methane. His companion, the Cassini spacecraft ,launched into Enceladus, another of the planet's more than 60 satellites, to fly over the south pole and traverse the vents emanating from its geysers. The analysis of the gases captured by their instruments indicate that they come from hydrothermal chimneys at the bottom of an ocean of liquid water on which there is an ice sheet several kilometers thick. These observations have turned Enceladus into one of two bodies in the Solar System most likely to harbor living things, according to NASA .

One of the most spectacular images of Saturn's rings, taken by Cassini in February 2017. AP

The Cassini spacecraft has also portrayed as never before the spectacular 300,000-kilometer ring system that is only 10 meters thick and resembles a young solar system.

During its last months of life , the probe has been passing through the gap between the rings and the planet, a totally unexplored area. With the data obtained try to solve some of the mysteries that remain to be addressed, such as establishing the mass of rings and know the duration of a day on Saturn. Unlike rocky planets such as Earth, where it is possible to reference a geographic point to know when an orbit has been completed, the gaseous atmosphere of the giant planet requires other methods. An instrument from the Cassini spacecraft allows you to measure the movements of Saturn's magnetic field and its radio emissions. Thus, it is known that a day there lasts between 10.6 and 10.8 hours, but the last days of service of the probe can solve the unknown exactly. Another great question to answer is whether the planet has a rocky core totally hidden under its stormy atmosphere.

The spacecraft entered the most superficial layers of Saturn's atmosphere at an altitude of 1,915 meters above the first clouds covering the planet, where the pressure is similar to that of Earth at sea level. It was expected to emit its last signal about 1,500 kilometers above the clouds.

Due to the distance between Saturn and Earth, the last goodbye of the Cassinispacecraft arrived 86 minutes after the spacecraft issued it. In the hours before its end the ship took its last images of the system of rings and of Enceladus and Titán. At the edge of midnight yesterday the probe sent all the data it had stored and its last images before changing its configuration to transmit in real time shortly before his controlled suicide.