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.
"We don't know how long the Dagwood-sandwich structure would exist. This structure represents a stable state, but various factors could mean the moon doesn't reach this stable state," Dr. Christophe Sotin said in a May 1, 2014 statement. Dr. Sotin is of the JPL.
The discovery of a moon for Makemake may have solved one perplexing puzzle concerning this distant, icy object. Earlier infrared studies of the dwarf planet showed that while Makemake's surface is almost entirely frozen and bright, some areas seem to be warmer than other areas. Astronomers had suggested that this discrepancy may be the result of our Sun warming certain dark patches on Makemake's surface. However, unless Makemake is in a special orientation, these mysterious dark patches should cause the ice dwarf's brightness to vary substantially as it rotates. But this amount of variability has not been observed.