... The first is the pointing accuracy of the FOC. The second is the internal geometric accuracy of an FOC image itself, including the correctness of the distortion model, the plate scale, and the image rotation. ... The accuracy with which HST places a target in the FOC field of view depends in a complex way on the target coordinate uncertainty, the positions of the guide stars in the FGS fields of view, and the alignment of the FOC imaging aperture with respect to the FGS reference frame. ...

... The science from both these missions contributed to three of the Nobel Prizes ­ Giacconi (2002), Mather, and Smoot (2006) - awarded for NASA-based science. ... We encourage NASA to seek new launch capabilities to fill this strategic gap in moderate lift rockets to enable the Explorer program to continue launching missions with significant science payoff but reduced costs and timescales compared to large strategic missions. ... 18 Appendix B: Explorer Missions 1989-present (From PILMSS) No . ...

ST-ECF Instrument Science Report ACS 2001-003 ACS Grism Simulations using SLIM 1.0 N. Pirzkal, A. Pasquali, J. R. Walsh, R. N. Hook, W. Freudling, R. Albrecht, R.A.E. Fosbury April 4, 2001 ABSTRACT We introduce SLIM, a slitless spectroscopy simulator written in Python which can be used to simulate the ACS grism and prism modes. ... We have thus developed a simulator called SLIM which is able to disperse an input spectrum in a well-controlled manner. ... Can simulate multiple order grism observations. ...

... 70 · Winter 2007 www.astrosociety.org/uitc © 2007, Astronomical Society of the Pacific 390 Ashton Avenue, San Francisco, CA 94112 Hubble Observations of Ceres and Pluto: A Closer Look at the "Ugly Ducklings" of the Solar System by Max Mutchler Space Telescope Science Institute Introduction regret that my 4th Grade teacher, Mrs. Hadley, doesn't know that she provided me with the very first astronomy book that I ever read, because it had a profound impact on me. ... Planet count 7 6 7 11 12 13 8 9 9? ...