Titan’s atmosphere is made mostly of nitrogen, like Earth’s, but with a surface pressure 50 percent higher than Earth’s. [204][205] On the other hand, Jonathan Lunine has argued that any living things in Titan's cryogenic hydrocarbon lakes would need to be so different chemically from Earth life that it would not be possible for one to be the ancestor of the other. Our solar system is home to more than 150 moons, but Titan is unique in being the only moon with a thick atmosphere. The concept probe is called Titan Lake In-situ Sampling Propelled Explorer (TALISE). [198] A life form whose solvent was a hydrocarbon would not face the risk of its biomolecules being destroyed in this way. The leading hemisphere has a 30% higher density than the trailing hemisphere. It is likely that the core is still hot, with a layer of liquid water and ammonia. Specular reflections are indicative of a smooth, mirror-like surface, so the observation corroborated the inference of the presence of a large liquid body drawn from radar imaging. Though similar in composition to Dione and Enceladus, it is denser due to gravitational compression. Titan is primarily composed of ice and rocky material, which is likely differentiated into a rocky core surrounded by various layers of ice, including a crust of ice Ih and a subsurface layer of ammonia-rich liquid water. Like Earth, Titan’s atmosphere is primarily nitrogen, plus a small amount of methane. [199] Although restating the biological hypothesis, he cautioned that other explanations for the hydrogen and acetylene findings are more likely: the possibilities of yet unidentified physical or chemical processes (e.g. Some of these features appear quite fresh, suggesting that such volcanic activity continues to the present. Bill Dunford, A 3D model of Titan, a moon of Saturn. ", "Saturn Moon Has Ice Volcano—And Maybe Life? [113], Scientists have long speculated that conditions on Titan resemble those of early Earth, though at a much lower temperature. Titan has a radius of about 1,600 miles (2,575 kilometers), and is nearly 50 percent wider than Earth’s moon. Site Manager: Researchers suspect methane could be belched into Titan's atmosphere by cryovolcanism—volcanoes releasing chilled water instead of molten rock lava—but they’re not certain if this or some other process is responsible. [186], It is hypothesized that large asteroid and cometary impacts on Earth's surface may have caused fragments of microbe-laden rock to escape Earth's gravity, suggesting the possibility of panspermia. Credit: NASA Visualization Technology Applications and Development (VTAD). Diameter [162], The proposed Titan Mare Explorer (TiME) was a low-cost lander that would splash down in a lake in Titan's northern hemisphere and float on the surface of the lake for three to six months. It does not have a molten core. The effect is more than just a cool visual. Let’s go right into it. Plumes of water vapor that may be venting into space from Jupiter's moon Europa could come from within the icy crust itself, according to new research. [109] This feature is thought to be an impact crater filled in by dark, windblown sediment. According to this hypothesis, methane is not emitted by volcanoes but slowly diffuses out of Titan's cold and stiff interior. While only the second largest of Titan's methane seas, Ligeia "contains enough liquid methane to fill three Lake Michigans". Opaque haze layers block most visible light from the Sun and other sources and obscure Titan's surface features. [147] It took images of Titan, including Titan and Saturn together in mid to late 1979. [105] Most large craters have breached or incomplete rims, despite the fact that some craters on Titan have relatively more massive rims than those anywhere else in the Solar System. The remaining 5% consists of methane and other molecules. the likely supplier is underground aquifers. [121] Prior to Cassini, scientists assumed that most of the topography on Titan would be impact structures, yet these findings reveal that similar to Earth, the mountains were formed through geological processes. Increased methane humidity at the south pole possibly contributes to the rapid increases in cloud size. The ground around their bases appears to be overlaid by frozen lava flows. That degree of warping suggests that Titan's interior is relatively deformable, and that the most likely model of Titan is one in which an icy shell dozens of kilometres thick floats atop a global ocean. However, its atmosphere provides a clue. Titan is larger than the planet Mercury and is the second largest moon in our solar system. [56], On September 30, 2013, propene was detected in the atmosphere of Titan by NASA's Cassini spacecraft, using its composite infrared spectrometer (CIRS). Titan’s internal structure isn’t entirely known, but one model based on data from the Cassini-Huygens mission suggests Titan has five primary layers. [160] The mission is tentatively planned to arrive at Titan in December 2034. IntroductionSaturn's largest moon, Titan, is an icy world whose surface is completely obscured by a golden hazy atmosphere. Infrared images from NASA's Juno spacecraft are providing the first glimpse of Ganymede's icy north pole. There is also evidence that Titan's ice shell may be substantially rigid,[36][37] which would suggest little geologic activity. Hyperion probably formed in a stable orbital island, whereas the massive Titan absorbed or ejected bodies that made close approaches.[26]. One possible mechanism for their formation is tidal forces from Saturn. Titan is resurfaced through the process by grain-sized ice and ammonium sulfate ash, which helps produce a wind-shaped landscape and sand dune features. Titan is never visible to the naked eye, but can be observed through small telescopes or strong binoculars. [77] It is criss-crossed in places by dark lineaments—sinuous topographical features resembling ridges or crevices. [17][18] Huygens was inspired by Galileo's discovery of Jupiter's four largest moons in 1610 and his improvements in telescope technology. [125], Crater-like landforms possibly formed via explosive, maar-like or caldera-forming cryovolcanic eruptions have been identified in Titan's polar regions. [62], Atmospheric methane creates a greenhouse effect on Titan's surface, without which Titan would be far colder. Titan orbits Saturn once every 15 days 22 hours. One AU is the distance from Earth to the Sun. Ligeia Mare averages from 20 to 40 m (66 to 131 ft) in depth, while other parts of Ligeia did not register any radar reflection at all, indicating a depth of more than 200 m (660 ft). [195] It has also been hypothesized that liquid-ammonia oceans could exist deep below the surface. [29] This rocky center is surrounded by several layers composed of different crystalline forms of ice. [64], Titan's clouds, probably composed of methane, ethane or other simple organics, are scattered and variable, punctuating the overall haze. [144] Titan has a maximum apparent magnitude of +8.2,[12] and mean opposition magnitude 8.4. The discovery of a global ocean of liquid water adds Titan to the handful of worlds in our solar system that could potentially contain habitable environments. The dunes break up around mountains, where the wind direction shifts. [36][37], The moons of Jupiter and Saturn are thought to have formed through co-accretion, a similar process to that believed to have formed the planets in the Solar System. [185][179], The Miller–Urey experiment and several following experiments have shown that with an atmosphere similar to that of Titan and the addition of UV radiation, complex molecules and polymer substances like tholins can be generated. [153] Titan is the most distant body from Earth to have a space probe land on its surface. Titan's modern geology would have formed only after the crust thickened to 50 kilometers and thus impeded constant cryovolcanic resurfacing, with any cryovolcanism occurring since that time producing much more viscous water magma with larger fractions of ammonia and methanol; this would also suggest that Titan's methane is no longer being actively added to its atmosphere and could be depleted entirely within a few tens of millions of years. The geologically young surface is generally smooth, with few impact craters, although mountains and several possible cryovolcanoes have been found. In 1907 Spanish astronomer Josep Comas i Solà observed limb darkening of Titan, the first evidence that the body has an atmosphere.