dipper@utastro.UUCP (Debbie Byrd) (10/25/84)
The planet Pluto is located directly behind the sun today. More on why astronomers will be looking for Pluto to come out of the sun -- right after this. October 25 Eclipses of Pluto and Charon On Thursday, the little planet Pluto will be directly behind the sun as seen from Earth. That means we can't see this outer world in our sky right now. But in the next month or so Pluto will come out of the sun -- into the morning sky -- and it's a sure bet some astronomers will be waiting to observe it. That's because Pluto and its tiny moon Charon are due soon to begin a series of eclipses of each other -- if they haven't started already. The eclipses will take place every 3.2 days for several years. By timing and studying eclipses of Pluto and its moon, astronomers will get much more information about the exact sizes and shapes of these two worlds. On that subject, it's interesting that Pluto rotates in about six days, and Charon takes the same length of time to travel once around Pluto. So a single hemisphere of Pluto permanently stares toward Charon, just as one face of our moon continually stares toward Earth. Because of this, it's thought that Pluto and Charon may not be round -- instead, they may be elongated in the direction of each other. Astronomers using eclipse data also hope to learn more about an atmosphere for Pluto -- which may sublime from ices on the surface of the planet only when Pluto is nearest the sun. And that's the case now. Pluto is now closer to the sun than Neptune -- and will be until the year 1999. Script by Deborah Byrd. (c) Copyright 1983, 1984 McDonald Observatory, University of Texas at Austin