Pluto Occultation 20/21 August 2002
Occultation Sequence Pluto Charon P :33 UT 6:26 UT7:03 UT 7:31 UT
Occultations by Pluto 2002 P131.1 Pluto + Star Pluto only Williams’s light curve from August 2002, taken at University of Hawaii 2.2-m telescope Pasachoff, Jay M., Steven P. Souza, Bryce A. Babcock, David R. Ticehurst (Williams College); James L. Elliot, M. J. Person, and Kelly B. Clancy (MIT); Lewis C. Roberts, Jr., and Doyle T. Hall (Boeing Co., Maui); and David J. Tholen (U. Hawaii) 2005, "The Structure of Pluto's Atmosphere from the 2002 August 21 Stellar Occultation," Astron. J., 129,
Occultation by Pluto 2002 P131.1 Pluto + Star Pluto only Williams’s light curve from August 2002, taken at University of Hawaii 2.2-m telescope Pasachoff, Jay M., Steven P. Souza, Bryce A. Babcock, David R. Ticehurst (Williams College); James L. Elliot, M. J. Person, and Kelly B. Clancy (MIT); Lewis C. Roberts, Jr., and Doyle T. Hall (Boeing Co., Maui); and David J. Tholen (U. Hawaii) 2005, "The Structure of Pluto's Atmosphere from the 2002 August 21 Stellar Occultation," Astron. J., 129, Pluto + Star Pluto only
Time (seconds after 8/21 06:40:00 UT) Normalized Flux UH 2.2-m/Williams CCD Light Curve
Half-light immersion time: : UT Half-light emersion time: : UT Duration: 5.15 minutes
Observations: Mauna Kea, 20 August 2002 Telescope: University of Hawaii 2.2 m f/10.14 CCD: Princeton Instruments (Roper Scientific) TE/CCD-576EFT frame-transfer CCD Frame Capture Rate = 2 Hz Resolution: 0.2 arc sec pixels unbinned for astrometric images binned 5x5 for 20-min occultation run Seeing: 0.4 arc sec Support: Research Corporation Technical Details
Zoom in of UH 2.2-m/Williams CCD Light Curve
Spikes, ingress and egress (flipped)
Haleakala data, I-band AEOS Telescope/Boeing LTS
Comparison of Light Curves Distance from Shadow Center (in units of half-light radius) Normalized Stellar Flux –0.5– –1.5
Changes in Pluto’s Atmospheric Pressure Emersion (2002) Emersion (1988) Pressure ( bar) Radius (km)
Papers published "High-Time-Resolution White-Light Observations of Pluto's Occultation of P131.1 in 2002 August” Elliot et al. "The recent expansion of Pluto's atmosphere," Nature 424, , July 10, Pasachoff et al. Astronomical Journal paper on our data. Person et al. Meeting paper on the shape of Pluto’s atmosphere.