The Face Behind The Veil. Titan is a little larger than Mercury--the smallest major planet inhabiting our Solar System. Indeed, Titan would have been classified as a major planet in its own right if it orbited our Sun instead of Saturn. The Huygens Probe images lifted the veil from the face of this distant moon-world, revealing a youthful surface that is both smooth and relatively free of impact craters. Huygens also found that this icy, hydrocarbon-saturated moon's climate includes those heavy rains of gasoline, as well as raging, roaring winds. Some of Titan's surface features were found to be hauntingly akin to certain surface features on Earth. Makemake, like Pluto, shows a red hue in the visible part of the electromagnetic spectrum. The near-infrared spectrum is marked by the existence of the broad methane absorption bands--and methane has also been observed on Pluto. Spectral analysis of Makemake's surface shows that its methane must be present in the form of large grains that are at least one centimeter in size. In addition to methane, there appears to be large quantities of ethane and tholins as well as smaller quantities of ethylene, acetylene, and high-mass alkanes (like propane)--most likely formed as a result of the photolysis of methane by solar radiation. The tholins are thought to be the source of the red color of the visible spectrum. Even though there is some evidence for the existence of nitrogen ice on Makemake's frozen surface, at least combined with other ices, it is probably not close to the same abundance of nitrogen seen on Pluto and on Triton. Triton is a large moon of the planet Neptune that sports a retrograde orbit indicating that it is a captured object. Many astronomers think that Triton is a wandering refugee from the Kuiper Belt that was captured by the gravity of its large, gaseous planet. It is possible that eventually the doomed Triton will plunge into the immense, deep blue world that it has circled for so long as an adopted member of its family. Nitrogen accounts for more than 98 percent of the crust of both Pluto and Triton. The relative lack of nitrogen ice on Makemake hints that its supply of nitrogen has somehow been depleted over the age of our Solar System. "Titan is a very active moon. We already know that about its geology and exotic hydrocarbon cycle. Now we can add another analogy with Earth and Mars: the active dust cycle, in which organic dust can be raised from large dune fields around Titan's equator," Dr. Sebastien Rodriguez explained in a September 24, 2018 NASA Jet Propulsion Laboratory (JPL) Press Release. Dr. Rodriguez is an astronomer at the Universite Paris Diderot, France, and the paper's lead author. The JPL is in Pasadena, California.