A black hole is a region of spacetime exhibiting gravitational acceleration so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary of the region from which no escape is possible is called the event horizon. Although the event horizon has an enormous effect on the fate and circumstances of an object crossing it, no locally detectable features appear to be observed. In many ways, a black hole acts like an ideal black body, as it reflects no light. Moreover, quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is on the order of billionths of a kelvin for black holes of stellar mass, making it essentially impossible to observe.
Each of the little Space eggs resides within its own ring arc--which is a fragmentary ring of Saturn. One hypothesis states that glittering ice crystals swarming around in the ring arc might be floating down to the surface of Methone, filling in its impact craters or other rough topography. This is something that is thought to have occurred on two other small, icy moons of Saturn--Atlas and Pan. Icy stuff swarming around in Saturn's rings apparently piled up around each moonlet's equator.
"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.
Organic dust forms when organic molecules, resulting from the interaction of sunlight with methane, grow large enough to tumble down to the surface of Titan. Dr. Roderiguez continued to explain that, even though this is the first-ever observation of a dust storm on Titan, the discovery is not especially surprising.