TY - JOUR
T1 - Visible and Near-IR Observations of the 2007 March 18 Occultation by Pluto
AU - Young, Leslie
AU - Bally, J.
AU - Bauer, J. M.
AU - Buie, M. W.
AU - Chanover, N. J.
AU - French, R. G.
AU - Hill, R. E.
AU - Hiriart, D.
AU - Holtzman, J. A.
AU - Howell, R. R.
AU - Jennings, D. E.
AU - Massey, P.
AU - Matthews, K. Y.
AU - Miko, L. R.
AU - Millis, R. L.
AU - Nicholson, P. D.
AU - Olkin, C. B.
AU - Owen, W. B.
AU - Plymate, C.
AU - Regester, J.
AU - Roe, H. G.
AU - Ruhland, C. R.
AU - Sada, P. V.
AU - Salas, L.
AU - Severson, S. A.
AU - Shoemaker, K.
AU - von Hippel, T.
AU - Young, E. F.
AU - Young, J. W.
AU - Zangari, A.
PY - 2007/10/1
Y1 - 2007/10/1
N2 - The predicted shadow path for the 2007 March 18 occultation of a 15.3
magnitude star by Pluto crossed western and central United States and
northern Mexico, including several large, fixed telescopes with infrared
instrumentation, with a slow sky-plane velocity (6.8 km/s, roughly three
times slower than typical). The PHOT (portable high-speed occultation
telescope) group used nineteen instruments at ten sites, with
wavelengths ranging from B to K. Our goal was multi-wavelength
observations to constrain atmospheric opacity, taking advantage of the
decrease of opacity with wavelength for photochemical hazes. We obtained
lightcurves from Red Buttes Observatory in Laramie WY (I), Lick
Observatory (H), Lowell Observatory (R, I, H), Palomar Observatory (I,
K), Mount Lemmon (I), Table Mountain Observatory (I), Kitt Peak National
Observatory (I, R, H, Ks), and San Pedro Martir (I, K). Weather
prevented observations at Apache Point Observatory and McDonald
Observatory. Our northernmost site, Red Buttes, was south of the central
line, but still reached the zero stellar flux level, and even our
southernmost site, San Pedro Martir, observed a grazing event. We see
little difference between visible and infrared observations. We see, for
the first time, well-defined high-altitude spikes caused by local
refocusing of starlight by small-scale density variations. We will
present the results of this varied dataset, including limits on or
evidence for hazes in Pluto's lower atmosphere.
AB - The predicted shadow path for the 2007 March 18 occultation of a 15.3
magnitude star by Pluto crossed western and central United States and
northern Mexico, including several large, fixed telescopes with infrared
instrumentation, with a slow sky-plane velocity (6.8 km/s, roughly three
times slower than typical). The PHOT (portable high-speed occultation
telescope) group used nineteen instruments at ten sites, with
wavelengths ranging from B to K. Our goal was multi-wavelength
observations to constrain atmospheric opacity, taking advantage of the
decrease of opacity with wavelength for photochemical hazes. We obtained
lightcurves from Red Buttes Observatory in Laramie WY (I), Lick
Observatory (H), Lowell Observatory (R, I, H), Palomar Observatory (I,
K), Mount Lemmon (I), Table Mountain Observatory (I), Kitt Peak National
Observatory (I, R, H, Ks), and San Pedro Martir (I, K). Weather
prevented observations at Apache Point Observatory and McDonald
Observatory. Our northernmost site, Red Buttes, was south of the central
line, but still reached the zero stellar flux level, and even our
southernmost site, San Pedro Martir, observed a grazing event. We see
little difference between visible and infrared observations. We see, for
the first time, well-defined high-altitude spikes caused by local
refocusing of starlight by small-scale density variations. We will
present the results of this varied dataset, including limits on or
evidence for hazes in Pluto's lower atmosphere.
M3 - Article
VL - 39
JO - American Astronomical Society, DPS meeting #50
JF - American Astronomical Society, DPS meeting #50
ER -