On March 18, the MMT recorded the occultation of the bright star P445.3 by Pluto. The above three frames, out of a sequence of 20,000, illustrate that sequence of events as recorded by the PISCES camera operating at 2.5 Hz in the H-band (1.6 microns). The observations were obtained at low elevation angle (20-35 deg., 3 airmasses) and illustrate the excellent atmospheric seeing characteristic of the MMT site. Individual frames easily resolve Pluto and its moon Charon with an angular separation of 0.7 arcsec. These exceptionally high signal-to-noise images revealed numerous unexpected scintillations as the starlight traversed Pluto's atmospheric layers. This work was part of a dual wavelength (H,V) experiment conducted by Arizona (Hubbard, Kulesa, McCarthy) and MIT (Elliot, Kern, Person). Shawn Callahan and the entire MMT staff provided extensive logistical support to make these observations successful. Images courtesy of Dr. Craig Kulesa, Steward Observatory.
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