Williams College Team Observes Occultation of a Star by Pluto!

A team from the Williams College Department of Astronomy has successfully observed the occultation of a faint star by the planet Pluto. Professor Jay M. Pasachoff, Dr. Bryce Babcock, and David Ticehurst '03 travelled to Mauna Kea, Hawaii, in an expedition arranged by Prof. James Elliot of MIT. Their local collaborator was Dr. David Tholen of the University of Hawaii. The Williams College group used a high-speed CCD camera on the 2.2-meter University of Hawaii telescope. In the images below Pluto is the brightest object in the field. Its satellite Charon is just below and to the left of Pluto. The star being occulted (designated P131.1) is just below and to the right or above and to the left of Pluto, depending on the time of the observation. The Williams team is collaborating on occultation observations with Dr. Elliot. Drs. Elliot and Tholen were on adjacent telescopes taking data in the infrared, which will be compared with the Williams College optical data to distinguish between conflicting models of Pluto's atmosphere. Other members of the expedition group on Mauna Kea were Kelly Clancy, Sheng "Jing Jing" Wu, David Osip, and Michael Person, all of MIT.

The Williams College expedition was supported by a grant from Research Corporation with additional support from NASA through the New Horizons Program and from Williams College.

Also see the article in Sky and Telescope.

and photos from the Pluto occultation expeditions.


25 Minutes Before Occultation

16 Minutes Before Occultation

10 Minutes Before Occultation

15 Minutes After Occultation


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