Speckle observations of 145 double stars and suspected double stars are presented and discussed. On the basis of multiple observations, a total of 280 position angle and separation measures are determined, as well as 23 high-quality nondetections. All observations were taken with the (unintensified) Rochester Institute of Technology fast-readout CCD camera mounted on the Lowell-Tololo 61 cm telescope at the Cerro Tololo Inter-American Observatory during 1999 October. We find that the measures, when judged as a whole against ephemeris positions of binaries with very well-known orbits, have root mean square deviations of (1.8+/- 0.3) degrees in position angle and (13+/-2) mas in separation. Eleven double stars discovered by Hipparcos were also successfully observed, and the change in position angle and/or separation since the Hipparcos observations was substantial in three cases (Refer to PDF file for exact formulas).

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Article may also be accessed on publisher's website at: http://www.journals.uchicago.edu/AJ/journal/contents/v120n5.html We are grateful to R. Millis of Lowell Observatory for his support of this project ; C. Enterline, O. Saa, and D. Maturana of CTIO for their help before and during the observing run; R. Argyle of the Institute for Astronomy, Cambridge, UK, for advice on the target list ; R. Easton of RIT for a timely loan of equipment; and the referee for comments regarding a few objects in Table 2. This work was funded by a grant from NASA administered by the American Astronomical Society and JPL subcontract 1201846 from the Preparatory Science Program for the Space Interferometry Mission.ISSN:1538-3881 Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

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Department, Program, or Center

Chester F. Carlson Center for Imaging Science (COS)


RIT – Main Campus