Titan (ancient Greek Τιτάν) is the largest satellite of Saturn, the second largest satellite in the solar system (after Jupiter's satellite Ganymede), is the only body in the solar system, except for the Earth, for which the stable existence of liquid on the surface has been proven, and the only planetary satellite with a dense atmosphere.
Titan became the first known satellite of Saturn - in 1655 it was discovered by the Dutch astronomer Christian Huygens.
The diameter of Titan is 5152 km (this is 1.48 times larger than that of the Moon), while Titan is 80% larger than the Earth's satellite in mass. Titan also surpasses the planet Mercury in size, although it is inferior to it in mass. The force of gravity on it is approximately one-seventh that on Earth. The mass of Titan is 95% of the mass of all the moons of Saturn.
The surface of Titan is mainly composed of water ice and sedimentary organic matter. It is geologically young and mostly flat, with the exception of a small number of rock formations and craters, as well as a few cryovolcanoes. The dense atmosphere surrounding Titan did not allow the surface of the satellite to be seen for a long time - until the arrival of the Cassini-Huygens apparatus in 2004.
The atmosphere is predominantly nitrogen; there is also a small amount of methane and ethane, which form the local ocean and clouds, which are the source of liquid and possibly solid precipitation. There are methane-ethane lakes and rivers on the surface. The pressure near the surface is about 1.5 times the pressure of the earth's atmosphere. The surface temperature is minus 170-180 °C.
Despite the low temperature, Titan is compared with the Earth in the early stages of development, and it cannot be ruled out that the existence of the simplest forms of life is possible on the satellite; in particular, in underground reservoirs, where conditions can be much more comfortable than on the surface.
History of discovery and name
Titan was discovered on March 25, 1655 by the Dutch physicist, mathematician and astronomer Christian Huygens. Inspired by the example of Galileo, Huygens, together with his brother Konstantin, created a telescope that had an aperture of 57 mm and a magnification factor of more than 50 times.
With this telescope, Huygens observed the planets of the solar systems