This is likely the first direct evidence of the presence of liquid channels on Titan and the first observation of hundred-meter deep canyons on Titan. No other world in the solar system, aside from Earth, has that kind of liquid activity on its surface.
[187], On April 3, 2013, NASA reported that complex organic chemicals could arise on Titan based on studies simulating the atmosphere of Titan.
This range lies in the southern hemisphere and is thought to be composed of icy material and covered in methane snow. At Titan's surface, water exists only in solid form. Titan’s atmospheric chemistry and the presence of complex organic compounds suggest that the moon may be a laboratory for studying the types of organic molecules and the chemical processes that led to the origin of life on Earth four billion years ago. These small particles absorb solar radiation and account for the deep brownish red tint.
Because sunlight continuously breaks down methane in Titan’s atmosphere, some source must be replenishing it or it would be depleted over time. [182], It has been speculated that life could exist in the lakes of liquid methane on Titan, just as organisms on Earth live in water. Only Jupiter's moon Ganymede is larger, by just 2 percent. This means that cryovolcanism on Titan would require a large amount of additional energy to operate, possibly via tidal flexing from nearby Saturn. [188] In 2016, the Cassini team announced what they believe to be the tallest mountain on Titan. Voyager 1's trajectory was designed to provide an optimized Titan flyby, during which the spacecraft was able to determine the density, composition, and temperature of the atmosphere, and obtain a precise measurement of Titan's mass.
The Cassini spacecraft discovered an extensive system of lakes filled with liquid hydrocarbons in the north polar region. Vast regions of dark dunes stretch across Titan’s landscape, primarily around the equatorial regions. [124], In December 2010, the Cassini mission team announced the most compelling possible cryovolcano yet found. Titan is also tidally locked in synchronous rotation with Saturn, meaning that, like Earth’s Moon, Titan always shows the same face to the planet as it orbits.
[133][135][138] Studies of dunes' composition in May 2008 revealed that they possessed less water than the rest of Titan, and are thus most likely derived from organic soot like hydrocarbon polymers clumping together after raining onto the surface. Even so, despite saying that a non-biological catalytic explanation would be less startling than a biological one, McKay noted that the discovery of a catalyst effective at 95 K (−180 °C) would still be significant. Titan’s veiling haze is probably composed of an aerosol of complex organic solids that are continuously produced by solar ultraviolet light falling on the nitrogen-methane atmosphere. The longitudinal (or linear) dunes were initially presumed to be formed by moderately variable winds that either follow one mean direction or alternate between two different directions. This is proposed to have been sufficient time for simple life to spawn on Earth, though the presence of ammonia on Titan would cause chemical reactions to proceed more slowly. Novemeber of 1980 and tried to take photographs, Titan's atmosphere is mostly nitrogen (about 95 percent) and methane (about 5 percent), with small amounts of other carbon-rich compounds. Titan’s atmosphere is similar to Earth’s both in the predominance of nitrogen gas and in surface pressure, which is about 1.5 bars, or 50 percent higher than sea-level pressure on Earth. Alternatively, the lineaments may be liquid-formed channels, suggesting old terrain that has been cut through by stream systems. Some of the compounds produced by that splitting and recycling of methane and nitrogen create a kind of smog—a thick, orange-colored haze that makes the moon's surface difficult to view from space.
When the probe arrived in the Saturnian system in 2004, it was hoped that hydrocarbon lakes or oceans would be detected from the sunlight reflected off their surface, but no specular reflections were initially observed.
[182] Heat transfer between the interior and upper layers would be critical in sustaining any subsurface oceanic life.
Further reactions have been studied extensively. A Discovery Program contestant for its mission #13 is Journey to Enceladus and Titan (JET), an astrobiology Saturn orbiter that would assess the habitability potential of Enceladus and Titan.
[33] Further supporting evidence for a liquid layer and ice shell decoupled from the solid core comes from the way the gravity field varies as Titan orbits Saturn. New analysis of data from NASA's Cassini spacecraft finds auroras at Saturn's poles may keep its atmosphere warm. They do know it is not homogeneous diameter of 5150 km (3,200 miles), There were indications that this situation would reverse, at least in part, as an equinox approached in 2010 and clouds in the northern temperate zones appeared for the first time. Subsequent observations showed the same feature better. Amanda Barnett It was first identified in infrared images from the Hubble Space Telescope in 1994, and later viewed by the Cassini spacecraft. [47], On October 24, 2014, methane was found in polar clouds on Titan. [47] Titan spends 95% of its time within Saturn's magnetosphere, which may help shield it from the solar wind. [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.
It is second in terms of relative diameter of moons to a gas giant; Titan being 1/22.609 of Saturn's diameter, Triton is larger in diameter relative to Neptune at 1/18.092. Global map of Titan – with IAU labels (August 2016). In March 2007, NASA, ESA, and COSPAR decided to name the Huygens landing site the Hubert Curien Memorial Station in memory of the former president of the ESA.[156]. a surface catalyst accepting hydrocarbons or hydrogen), or flaws in the current models of material flow. [119] No similar features have been identified as of 2010. [134] Dunes of this type are always aligned with average wind direction. [63] Conversely, haze in Titan's atmosphere contributes to an anti-greenhouse effect by reflecting sunlight back into space, cancelling a portion of the greenhouse effect and making its surface significantly colder than its upper atmosphere. The continent-size region Xanadu Regio shows as the large bright patch on the right, while bright methane clouds appear near Titan's south pole. 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.
[198] A life form whose solvent was a hydrocarbon would not face the risk of its biomolecules being destroyed in this way. The mountainous ridges observed in some regions can be explained as heavily degraded scarps of large multi-ring impact structures or as a result of the global contraction due to the slow cooling of the interior. Titan’s surface, like Earth’s, is sculpted by wind and probably also rain (in the form of liquid methane). On the other hand, the hotter the atmosphere, the more likely it is that the molecule will be lost to space. With its liquids (both surface and subsurface) and robust nitrogen atmosphere, Titan's methane cycle is analogous to Earth's water cycle, at the much lower temperature of about 94 K (−179.2 °C; −290.5 °F). [32] Surface features were observed by the Cassini spacecraft to systematically shift by up to 30 kilometers (19 mi) between October 2005 and May 2007, which suggests that the crust is decoupled from the interior, and provides additional evidence for an interior liquid layer. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox.