+ Visit NASA.gov + Contact NASA   + Home Collection > NASA  Author > Abercromby, Kira J.  Author > Barker, Ed  Author > Foreman, Gary  Author > Horstman, Matt  Author > Rodriguez-Cowardin, Heather M.  Author > Seitzer, Patrick  NASA Center > Johnson Space Center  Publication Year > 2001-2010 > 2009  Subject > A-C > Astronomy  Availability Options > Order From CASI > CD-ROM, DVD, Print  Item/Media Type > Conference Paper  Note: Start a new navigation search by selecting a link above     Previous Record | Next Record + Back to Results   + Printer Friendly Title: Photometric Studies of Orbital Debris at GEO Author(s): Seitzer, Patrick; Abercromby, Kira J.; Rodriguez-Cowardin, Heather M.; Barker, Ed; Foreman, Gary; Horstman, Matt Abstract: We report on optical observations of debris at geosynchronous Earth orbit (GEO) using two telescopes simultaneously at the Cerro Tololo Inter-American Observatory (CTIO) in Chile. The University of Michigan s 0.6/0.9-m Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope) was used in survey mode to find objects that potentially could be at GEO. Because GEO objects only appear in this telescope s field of view for an average of 5 minutes, a full six-parameter orbit can not be determined. Interrupting the survey for follow-up observations leads to incompleteness in the survey results. Instead, as objects are detected with MODEST, initial predictions assuming a circular orbit are done for where the object will be for the next hour, and the objects are reacquired as quickly as possible on the CTIO 0.9-m telescope. This second telescope follows-up during the first night and, if possible, over several more nights to obtain the maximum time arc possible, and the best six parameter orbit. Our goal is to obtain an initial orbit and calibrated colors for all detected objects fainter than R = 15th in order to estimate the orbital distribution of objects selected on the basis of two observational criteria: magnitude and angular rate. One objective is to estimate what fraction of objects selected on the basis of angular rate are not at GEO. A second objective is to obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. NASA Center: Johnson Space Center Publication Date: January 2009 Document Source: CASI No Digital Version Available: Go to Tips On Ordering Document ID: 20090001317 Publication Information: Number of Pages = 2 Price Code: A01 Meeting Information: 5th European Conference on Space Debris, 30 Mar. - 2 Apr. 2009, Darmstadt, Germany Keywords: GEOSYNCHRONOUS ORBITS; SCHMIDT TELESCOPES; VISUAL OBSERVATION; FIELD OF VIEW; SPACE DEBRIS; CIRCULAR ORBITS; ASTRONOMY; SURVEYS; MAGNITUDE; Accessibility: Unclassified; Copyright; Unlimited; Publicly available; Updated/Added to NTRS: 2009-01-15 + Back to Top + Sponsored by the NASA Scientific and Technical    Information Program + 2004 Vision for Space Exploration + Freedom of Information Act + NASA Web Privacy Policy and Important Notices + NASA Disclaimers, Copyright Notice,    and Terms and Conditions of Use NASA Official: Calvin Mackey Page Curator: NASA Center for AeroSpace Information (help@sti.nasa.gov) Last Updated: July 5, 2007