Just trying to get some sort of credit for the assignment! Trying to finish out the rest of my assignments because at the moment I have no time. Feel free to message me with any questions regarding the assignment.

An occultation occurs when a planet blocks the light from a more distant object. pPluto_Charone.JPG The image above shows how such an occultation occurs when Charon passes in front of Pluto. 1. The first contact occurs when the limb of Charon just touches the limb of Pluto. 2. Second contact occurs at the moment when the moon is completely in front of Pluto. 3. Third contact occurs when Charon is just beginning to emerge from in front of Pluto. 4. Fourth contact is when Charon is completely away from Pluto again. The length of time between the first and second contacts is a function of the velocity of the Charon and its diameter. The time between the first contact and the third contact is also a function of Charon's velocity and the diameter of Pluto. We can measure these time intervals and assuming we know the velocity of Charon we can estimate the diameter of both Pluto and Charon. But it is impossible to actually see Charon and Pluto separately except in really large telescopes. Instead one can observe the amount of light that was received from the Pluto-Charon system. When both Pluto and Charon are side-by-side, telescopes will receive a relatively large amount of light. When Pluto passes in front of Charon or when Charon passes in front of Pluto, the amount of light decreases. By attaching light sensitive instruments- photomoeters - to telescopes, astronomers could measure the changes in light during the occultations. A graph of the intensity of light versus time could then be plotted, from the point when one edge of Charon touches Pluto, to when Charon is entirely in front of Pluto, to when Charon just begins to re-emerge from in front of Pluto, and finally to when Charon completely moves away from being in front of Pluto (the figure above is an idealized depiction of such an event). These four different events are marked by distinct changes in the light from the two objects, and the pattern of change in light is made obvious when you construct a light curve from the photometric data. By determining the (time) length of the occultation from the light curve, we can then calculate the diameters of the planet and moon from the elapsed times and the known velocity of Charon in its orbit. (distance = velocity x time ) Pluto_Charon_LabPreview the document Estimating Charon's diameter assuming we know Pluto's Diameters You need to enter time as decimals (ex. 14:30 is 2.5 and 14:45 is 2.75).