Hua Feng learned that the Titan in the back was made of ice, with a density of about 1.233 g/cm. This low density shows that it is composed of 25% rock (density 3.250 g/cm) and 75% water ice (density 1.000 g/cm). Although Titan is the 9th largest moon in the solar system, it can only rank 10th in terms of mass.

Early astronomers estimated that it had a rocky core. However, Cassini's close-range detection results show that its axial moment of inertia coefficient is 0.4 kg, which indicates that the interior of Titan is almost the same material, because the presence of a rocky core will cause the mass moment of inertia to fall to about 3.4. The three-dimensional model of Titan is also hydrostatically equilibrate.

Titan's characteristics are somewhat similar to Titan's, suggesting that they may have similar compositions and histories. The temperature in the sunlit area of Titan is 99°C (−174°C), while the temperature in the shaded areas is between −200°C and −220°C.

Titan's surface has noticeable pitting and bright subtle features. Its surface can be divided into two different geographical regions according to the density of craters, the first region consists of craters with a diameter of more than 40 axioms, while the second area is the opposite, located in the polar and equatorial regions. This also shows that there was a large-scale reorganization event during the formation of Titan.

The main hemisphere received a severe blow and was very bright. Like the craters on Callisto, the craters on Titan lack the obvious features that can be observed on the Moon and Mercury. Bright webs can be seen on the black surface of the ground in the other hemisphere, and a few potholes can be discerned. These bright areas were thought to have erupted from an icy volcano in the early days of Titan. However, recent observations of Titan have shown that the bright stripes scattered across the surface are actually cliffs made of ice, so astronomers speculate that the stripes on Titan are also cliffs made of ice.

Cassini flew close to Titan on January 17, 2006, and took a series of high-resolution photographs. While scientific analysis is still ongoing, the photos show that the stripes on Titan's surface resemble Titan's striped structure, which are actually ice cliffs.

NASA announced on March 6, 2008 that Titan may have a thin ring, the first time a ring-belt system has been discovered on a satellite. The existence of this ring system was inferred by Cassini's discovery that Saturn's magnetic field has a high-energy flow of electrons near Titan. Dust and debris extend into Titan's Hill sphere area, but are denser near Titan, suggesting that Titan may have 3 dense bands of thin rings.

Cassini took a number of pictures of Titan at close range, the closest of which was taken on November 26, 2005, just 500 kilometers away. Another close overflight was on 30 August 2007 at a distance of 5,750 kilometres. The Cassini Extension Mission is scheduled to pass Titan from a distance of 100 kilometers on March 2, 2010.

When NASA Cassini approached Saturn's Titan, a narrow-angle camera with a sensitive infrared band (930 nm) color filter used visible light to photograph the south pole region of Titan, and the distance between Enceladus and Cassini was about 239,000 kilometers, and the angle between the sun, Titan and Cassini was 56 degrees, with a resolution of about 1 kilometer per line.

Like the rest of Titan's surface, its Antarctic region has been riddled with craters for millions of years, and these detailed photographs show that the larger craters are littered with pockmarked craters. On the left of the photo shown, a more interesting trench can be seen, the clearest crater in the upper right part of the photo has an elliptical shape, it has a size of 115×91 kilometers.

The Cassini-Huygens flight is a joint program of NASA with the European Space Agency and the Italian Space Agency, and the control of the Cassini probe is entrusted to NASA's Jet Propulsion Laboratory in Pasadena, California, USA.

The National Aeronautics and Space Administration (NASA) has released a rare video image of Titan captured by the Cassini Saturn probe. It is precious because the 15-second video captures the entire eclipse on Titan. The video released this time consists of a total of 17 images and was taken on August 19, 2008.

At that time, Titan was gradually moving into the shadow region of Saturn. It is clear from the video that the edges of Saturn's shadow cast on Titan are very blurred, which is very different from the shadow cast by the Moon on Earth. Experts point out that this discrepancy occurs mainly because Saturn is a gas planet, and its outer boundaries are not very clear on their own, which leads to the shadows it produces are not very clear.

The tiny moon Titan hanging in front of Saturn's rings is like a pearl. At the beginning of November last year, Cassini, orbiting the spacecraft, enjoyed this rare sight. The photo is not the "original", but is rotated.

The name "Cassini" comes from the Italian astronomer Giovanni Domenico Cassini, who discovered Titan in 1672. Astronomers announced in 2008 that Titan could be the first moon known to have its own dim ring system.

According to NASA, Cassini was about 450,000 kilometers away from Titan when the video was taken, and the resolution of the image was 2.7 kilometers.

It has a diameter of 1,528 kilometers and an average distance of about 500,000 kilometers from Saturn. So far, Cassini has successfully created a panoramic image of Titan's surface. The most interesting discovery about this celestial object appeared in the summer of 2008. At the time, astronomers pointed out that Titan may also have its own halo system. They explained that the detection equipment on board Cassini found that Titan was surrounded by a large amount of debris, forming a disc-shaped debris belt with a range of thousands of kilometers. Observations have shown that there are also areas of rapid reduction in the number of electrons on both sides of Titan.

Scientists then conducted extensive simulations to determine whether Titan had the ability to stabilize such a ring structure. The results show that the rings around Titan can be stable for a long time due to the combined effect of the Titan gravitational field and its orbit around Saturn. Scientists believe that the reason why Titan has a ring may be because an asteroid or comet collided with Titan in the distant past, and the resulting debris drifted around and gradually gathered into a halo.

Titan is Saturn's largest moon and the second largest moon in the solar system, larger than the planet Mercury (although not as massive as Mercury), and only smaller in the solar system than Jupiter's largest moon, Ganymede. But recent observations have also shown that the dense atmosphere may have led to an overestimation of Titan's diameter, which, like many other moons, is larger than the mass and volume of asteroid 134340 (pro-Pluto).

The average radius of Titan is 2575 km, the mass is 1.345×10²³ kg, and the average density is 1.880×10³ kg/m³. Titan's orbit around Saturn has a semi-major diameter of 1,221,850 km, an eccentricity of 0.0292, an angle of 0.33° between the orbital plane and Saturn's equatorial plane, and an orbital period of 15 days, 22 hours, 41 minutes and 24 seconds. Titan's rotation period is the same as its revolution, which is similar to that of the Moon. Titan has a dense atmosphere, the main component is nitrogen, a surface atmospheric pressure of 1.5×10⁵Pascal, and a surface temperature of -179.15°C.

Titan's mass is roughly similar to that of Ganymede, Ganymede, Triton, and the asteroid 134340 (Pluto). Titan is half water ice and half solid material. There is a solid core at 3400 meters below multiple different crystalline ice formations. The inside of the core should still be red-hot. While Titan and other moons of Saturn are similar, Titan's core is denser because of its sheer size, which causes gravity to compress its interior.

Atmospheric conditionsTitan is the only moon known to have a true atmosphere, and the rest of the satellites only have tracer gas at best. The presence of the atmosphere was first identified in 1944 by Ge Gilard Kuiper

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Using a spectroscopic telescope, he found that the local pressure of methane in Titan's atmosphere reached 100 millibars. Later, observations by the Voyager spacecraft also confirmed that Titan has an atmosphere on it, and in fact, the atmospheric pressure on Titan is slightly greater than that of Earth, and the pressure on the planet's surface is 1.5 times that of Earth.

Titan's surface is obscured by dense clouds. It is generally believed that the surface of Titan is solid or liquid ethane. Radar measurements from the Earth have shown that there is no large ethane ocean, but it is still possible that small ethane lakes exist. Later, scientists studied the images sent back by the Cassini spacecraft and concluded that there may not be an ocean of liquid methane on Titan.

Researchers who had observed Titan through ground-based telescopes believed that there were signs of a possible liquid ocean on Saturn's moon. However, scientists still have doubts about the conclusions reached, because previous observations have shown that there is indeed a flickering reflection of liquid on the surface of Titan, especially from a large radio telescope a few years ago, which proves that a liquid ocean is highly likely.

Titan's atmosphere is 98.44% nitrogen, the only nitrogen-rich star in the solar system other than Earth, where there are large residues of different kinds of hydrocarbons (including methane, ethane, butylene, propyne, propynitrile, acetylene, propane, as well as carbon dioxide, cyanide, hydrogen cyanide, and helium). These hydrocarbons are thought to come from methane in Titan's upper atmosphere. When methane reacts in response to solar radiation, it produces a dense cloud of orange-red smoke. The organic precipitate on the surface of Titan, which appears to be coated with a layer of tar, is called tholi

。 Titan is not protected by a magnetic field, so when it sometimes orbits outside Saturn's magnetosphere, it is directly exposed to the solar wind. This causes the atmosphere to ionize and release some molecules in the upper layers of the atmosphere.

Approaching the surface, Titan's temperature is approximately 94 K (-179.15 °C). Water ice sublimates at this temperature, so there is a small amount of water vapor in the atmosphere. Clouds may be made up of methane, ethane, or simple organic matter. Other rare complex chemicals are responsible for Titan's orange appearance in space.

In November 2004, Cassini flew past the bright and cloudy South Pole in the Titan photograph but did not find the desired methane to exist.

Cassini's 2004 observations of the atmosphere found that Titan's atmosphere "super-rotates", like Venus, and its atmosphere rotates much faster than the surface.

According to Science Daily, physicists from the University of Granada and the University of Valencia in Spain have unequivocally confirmed the existence of natural electrical activity such as lightning storms in Titan's atmosphere by analyzing the special observation data of the Huygens probe on Titan. Scientific groups believe that organic molecules, early life forms, may have formed in the upper atmospheres of planets or moons with thunderstorms.

Since 1908, when Spanish astronomer Josie Comas Sula discovered that Titan has an atmosphere, no atmosphere has been found on other moons. "Atmospheric clouds with transitive motion are formed on Titan, so static electric fields and storm conditions can form," he explained. According to the theories of Russian biochemist Alexander Opakin and the experiments of Stanley Miller, Titan's thunderstorm-active atmosphere may form organic matter and early life forms, and under these conditions, organic compounds can be synthesized from inorganic mixtures by releasing electricity.