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class="offcanvas__section-link" >System Throughputs</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/acs/data-analysis/zeropoints' class="offcanvas__section-link" >Zeropoints</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/acs/data-analysis/photometric-transformations' class="offcanvas__section-link" >Photometric Transformations</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/acs/calibration' class="offcanvas__section-link" >Calibration</a><button class="offcanvas__section-toggle" id="Calibration_22_control" type="button" aria-label="Calibration submenu" aria-controls="Calibration_22_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use 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class="offcanvas__section-link" >Cycle 28 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-27-calibration-plan' class="offcanvas__section-link" >Cycle 27 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-26-calibration-plan' class="offcanvas__section-link" >Cycle 26 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-25-calibration-plan' class="offcanvas__section-link" >Cycle 25 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-24-calibration-plan' class="offcanvas__section-link" >Cycle 24 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-23-calibration-plan' class="offcanvas__section-link" >Cycle 23 Calibration Plan</a></li><li class="offcanvas__item 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href='/hst/instrumentation/stis/observing-strategies/available-modes/high-contrast-coronagraphy-at-small-inner-working-angles-with-bar5' class="offcanvas__section-link" >High Contrast Coronagraphy at Small Inner Working Angles with BAR5</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/stis/observing-strategies/available-modes/stis-bar5' class="offcanvas__section-link" >STIS BAR5</a></li></ul></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/stis/data-analysis-and-software-tools' class="offcanvas__section-link" >Data Analysis and Software Tools</a><button class="offcanvas__section-toggle" id="Data_Analysis_and_Software_Tools_40_control" type="button" aria-label="Data Analysis and Software Tools submenu" aria-controls="Data_Analysis_and_Software_Tools_40_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use 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Handbook</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='https://hst-docs.stsci.edu/stisdhb' class="offcanvas__section-link" target='_blank' >STIS Data Handbook</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/stis/flux-recalibration' class="offcanvas__section-link" >Flux Recalibration</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3' class="offcanvas__section-link" >Wide Field Camera 3</a><button class="offcanvas__section-toggle" id="Wide_Field_Camera_3_42_control" type="button" aria-label="Wide Field Camera 3 submenu" aria-controls="Wide_Field_Camera_3_42_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Wide_Field_Camera_3_42_section" class="offcanvas__list" data-level="4" aria-labelledby="Wide_Field_Camera_3_42_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/instrument-design' class="offcanvas__section-link" >Instrument Design</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/performance' class="offcanvas__section-link" >Performance</a><button class="offcanvas__section-toggle" id="Performance_43_control" type="button" aria-label="Performance submenu" aria-controls="Performance_43_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Performance_43_section" class="offcanvas__list" data-level="5" aria-labelledby="Performance_43_control"><li 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aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Monitoring_44_section" class="offcanvas__list" data-level="6" aria-labelledby="Monitoring_44_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/wfc3/performance/monitoring/complete-anneal-history' class="offcanvas__section-link" >Complete Anneal History</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/performance/throughputs' class="offcanvas__section-link" >Throughputs</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/performance/cal-subsystem' class="offcanvas__section-link" >Cal Subsystem</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/proposing' class="offcanvas__section-link" >Proposing</a><button class="offcanvas__section-toggle" id="Proposing_45_control" type="button" aria-label="Proposing submenu" aria-controls="Proposing_45_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Proposing_45_section" class="offcanvas__list" data-level="5" aria-labelledby="Proposing_45_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/proposing/dithering-strategies' class="offcanvas__section-link" >Dithering Strategies</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/proposing/exception-reports' class="offcanvas__section-link" >Exception Reports</a></li></ul></li><li class="offcanvas__item hasChildren"><a 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href='/hst/instrumentation/wfc3/data-analysis/full-well-depth' class="offcanvas__section-link" >Full Well Depth</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources' class="offcanvas__section-link" >Grism Spectroscopy</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis/ir-flats' class="offcanvas__section-link" >IR Flats</a><button class="offcanvas__section-toggle" id="IR_Flats_47_control" type="button" aria-label="IR Flats submenu" aria-controls="IR_Flats_47_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="IR_Flats_47_section" class="offcanvas__list" data-level="6" aria-labelledby="IR_Flats_47_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/ir-flats/blob-delta-flats-from-earth-flat-calibration-images' class="offcanvas__section-link" >Blob Delta-flats from Earth Flat Calibration Images</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/ir-persistence' class="offcanvas__section-link" >IR Persistence</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration' class="offcanvas__section-link" >Photometric Calibration</a><button class="offcanvas__section-toggle" id="Photometric_Calibration_48_control" type="button" aria-label="Photometric Calibration submenu" aria-controls="Photometric_Calibration_48_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Photometric_Calibration_48_section" class="offcanvas__list" data-level="6" aria-labelledby="Photometric_Calibration_48_control"><li class="offcanvas__item hasChildren firstInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-photometric-calibration' class="offcanvas__section-link" >UVIS Photometric Calibration</a><button class="offcanvas__section-toggle" id="UVIS_Photometric_Calibration_49_control" type="button" aria-label="UVIS Photometric Calibration submenu" aria-controls="UVIS_Photometric_Calibration_49_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="UVIS_Photometric_Calibration_49_section" class="offcanvas__list" data-level="7" aria-labelledby="UVIS_Photometric_Calibration_49_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-photometric-calibration/quad-filter-photometry' class="offcanvas__section-link" >Quad Filter Photometry</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-photometric-calibration/uv-filter-modified-keywords' class="offcanvas__section-link" >UV Filter Modified Keywords</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-photometric-calibration/previous-uvis-photometric-calibrations' class="offcanvas__section-link" >Previous UVIS Photometric Calibrations</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-encircled-energy' class="offcanvas__section-link" >UVIS Encircled Energy</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/ir-photometric-calibration' class="offcanvas__section-link" >IR Photometric Calibration</a><button class="offcanvas__section-toggle" id="IR_Photometric_Calibration_50_control" type="button" aria-label="IR Photometric Calibration submenu" aria-controls="IR_Photometric_Calibration_50_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="IR_Photometric_Calibration_50_section" class="offcanvas__list" data-level="7" aria-labelledby="IR_Photometric_Calibration_50_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/ir-photometric-calibration/previous-ir-photometric-calibrations' class="offcanvas__section-link" >Previous IR Photometric Calibrations</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/ir-encircled-energy' class="offcanvas__section-link" >IR Encircled Energy</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/pixel-area-maps' class="offcanvas__section-link" >Pixel Area Maps</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis/psf' class="offcanvas__section-link" >PSF</a><button class="offcanvas__section-toggle" id="PSF_51_control" type="button" aria-label="PSF submenu" aria-controls="PSF_51_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="PSF_51_section" class="offcanvas__list" data-level="6" aria-labelledby="PSF_51_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/psf/psf-search' class="offcanvas__section-link" >PSF Search</a></li></ul></li><li class="offcanvas__item noChildren"><a href='http://archive.stsci.edu/hst/index.html' class="offcanvas__section-link" target='_blank' >Retrieving Data</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/should-i-recalibrate' class="offcanvas__section-link" >Should I Recalibrate?</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/uvis-flats' class="offcanvas__section-link" >UVIS Flats</a></li><li class="offcanvas__item noChildren"><a href='/hst/observing/post-observation' class="offcanvas__section-link" >Post-Observation</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/uvis-and-ir-distortion-calibration' class="offcanvas__section-link" >UVIS and IR Distortion Calibration</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/calibration-plan' class="offcanvas__section-link" >Calibration Plan</a><button class="offcanvas__section-toggle" id="Calibration_Plan_52_control" type="button" aria-label="Calibration Plan submenu" aria-controls="Calibration_Plan_52_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Calibration_Plan_52_section" class="offcanvas__list" data-level="5" aria-labelledby="Calibration_Plan_52_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/calibration-plan/tv3-results' class="offcanvas__section-link" >TV3 Results</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/calibration-plan/tv2-results' class="offcanvas__section-link" >TV2 Results</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/calibration-plan/tv1-results' class="offcanvas__section-link" >TV1 Results</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/calibration-plan/old-versions' class="offcanvas__section-link" >Old Versions</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/software-tools' class="offcanvas__section-link" >Software Tools</a><button class="offcanvas__section-toggle" id="Software_Tools_53_control" type="button" aria-label="Software Tools submenu" aria-controls="Software_Tools_53_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Software_Tools_53_section" class="offcanvas__list" data-level="5" aria-labelledby="Software_Tools_53_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/software-tools/crosstalk' class="offcanvas__section-link" >Crosstalk</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/software-tools/cte-tools' class="offcanvas__section-link" >CTE Tools</a></li><li class="offcanvas__item noChildren"><a 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section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Grism_Resources_55_section" class="offcanvas__list" data-level="6" aria-labelledby="Grism_Resources_55_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/grism-data-analysis' class="offcanvas__section-link" >Grism Data Analysis</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/wfc3-ir-grism-data-reduction-cookbook' class="offcanvas__section-link" >WFC3 IR Grism Data Reduction Cookbook</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/grism-frequently-asked-questions' class="offcanvas__section-link" >Grism Frequently Asked Questions</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/ir-grism-sky-images' class="offcanvas__section-link" >IR Grism Sky Images</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/wfc3-g141-calibrations' class="offcanvas__section-link" >WFC3 G141 Calibrations</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/wfc3-g280-calibrations' class="offcanvas__section-link" >WFC3 G280 Calibrations</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/wfc3-g102-calibrations' class="offcanvas__section-link" >WFC3 G102 Calibrations</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/uvis-grism-sky-images' class="offcanvas__section-link" >UVIS Grism Sky Images</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/documentation/conference-posters' class="offcanvas__section-link" >Conference Posters</a></li></ul></li><li 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href='/hst/instrumentation/focus-and-pointing/focus' class="offcanvas__section-link" >Focus</a><button class="offcanvas__section-toggle" id="Focus_57_control" type="button" aria-label="Focus submenu" aria-controls="Focus_57_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Focus_57_section" class="offcanvas__list" data-level="5" aria-labelledby="Focus_57_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/focus-and-pointing/focus/secondary-mirror-moves' class="offcanvas__section-link" >Secondary Mirror Moves</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/focus-and-pointing/focus/hst-focus-model' class="offcanvas__section-link" >HST Focus Model</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/focus-and-pointing/focus/tiny-tim-hst-psf-modeling' class="offcanvas__section-link" >Tiny Tim HST PSF Modeling</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/focus-and-pointing/pointing' class="offcanvas__section-link" >Pointing</a><button class="offcanvas__section-toggle" id="Pointing_58_control" type="button" aria-label="Pointing submenu" aria-controls="Pointing_58_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Pointing_58_section" class="offcanvas__list" data-level="5" aria-labelledby="Pointing_58_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/focus-and-pointing/pointing/jitter-file-format-definition' class="offcanvas__section-link" >Jitter File Format Definition</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/focus-and-pointing/pointing/determining-an-observations-orientation' class="offcanvas__section-link" >Determining an Observation鈥檚 Orientation</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/focus-and-pointing/fov-geometry' class="offcanvas__section-link" >FoV Geometry</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/focus-and-pointing/documentation' class="offcanvas__section-link" >Documentation</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/legacy' class="offcanvas__section-link" >Legacy Instruments</a><button class="offcanvas__section-toggle" id="Legacy_Instruments_59_control" type="button" aria-label="Legacy Instruments submenu" aria-controls="Legacy_Instruments_59_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Legacy_Instruments_59_section" class="offcanvas__list" data-level="4" aria-labelledby="Legacy_Instruments_59_control"><li class="offcanvas__item hasChildren firstInLevel"><a href='/hst/instrumentation/legacy/nicmos' class="offcanvas__section-link" >NICMOS</a><button class="offcanvas__section-toggle" id="NICMOS_60_control" type="button" aria-label="NICMOS submenu" aria-controls="NICMOS_60_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="NICMOS_60_section" class="offcanvas__list" data-level="5" aria-labelledby="NICMOS_60_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/legacy/nicmos/instrument-science-reports-isrs' class="offcanvas__section-link" >Instrument Science Reports (ISRs)</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/legacy/wfpc2' class="offcanvas__section-link" >WFPC2</a><button class="offcanvas__section-toggle" id="WFPC2_61_control" type="button" aria-label="WFPC2 submenu" aria-controls="WFPC2_61_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="WFPC2_61_section" class="offcanvas__list" data-level="5" aria-labelledby="WFPC2_61_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/legacy/wfpc2/instrument-science-reports-isrs' class="offcanvas__section-link" >Instrument Science Reports (ISRs)</a></li></ul></li></ul></li><li class="offcanvas__item hasChildren lastInLevel"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools' class="offcanvas__section-link" >Reference Data for Calibration and Tools</a><button class="offcanvas__section-toggle" id="Reference_Data_for_Calibration_and_Tools_62_control" type="button" aria-label="Reference Data for Calibration and Tools submenu" aria-controls="Reference_Data_for_Calibration_and_Tools_62_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Reference_Data_for_Calibration_and_Tools_62_section" class="offcanvas__list" data-level="4" aria-labelledby="Reference_Data_for_Calibration_and_Tools_62_control"><li class="offcanvas__item noChildren firstInLevel"><a href='https://hst-crds.stsci.edu/' class="offcanvas__section-link" target='_blank' >Calibration Reference Data System (CRDS)</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/file-and-table-structures' class="offcanvas__section-link" >File and Table Structures</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/reference-file-retreival-instructions' class="offcanvas__section-link" >Reference File Retrieval Instructions</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/legacy-instrument-reference-files' class="offcanvas__section-link" >Legacy Instrument Reference Files</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/synphot-throughput-tables' class="offcanvas__section-link" >Synphot Throughput Tables</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs' class="offcanvas__section-link" >Astronomical Catalogs</a><button class="offcanvas__section-toggle" id="Astronomical_Catalogs_63_control" type="button" aria-label="Astronomical Catalogs submenu" aria-controls="Astronomical_Catalogs_63_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Astronomical_Catalogs_63_section" class="offcanvas__list" data-level="5" aria-labelledby="Astronomical_Catalogs_63_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/the-agn-atlas' class="offcanvas__section-link" >The AGN Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/atmo-2020-atmosphere-models' class="offcanvas__section-link" >ATMO 2020 Atmosphere Models</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/brown-dwarfs-and-substellar-objects' class="offcanvas__section-link" >Brown Dwarfs and Substellar Objects</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/bruzual-atlas' class="offcanvas__section-link" >Bruzual Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/the-bruzual-charlot-atlas' class="offcanvas__section-link" >The Bruzual-Charlot Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/bruzual-and-charlot-2003' class="offcanvas__section-link" >Bruzual and Charlot 2003</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/bruzual-persson-gunn-stryker-atlas-list' class="offcanvas__section-link" >Bruzual-Persson-Gunn-Stryker Atlas list</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/buser-kurucz-atlas' class="offcanvas__section-link" >Buser-Kurucz Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/calobs' class="offcanvas__section-link" >CALOBS</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/calspec' class="offcanvas__section-link" >CALSPEC</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/castelli-and-kurucz-atlas' class="offcanvas__section-link" >Castelli and Kurucz Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/composite-qso-spectra-for-nir' class="offcanvas__section-link" >Composite QSO Spectra for NIR</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/the-galactic-emission-line-object-atlas' class="offcanvas__section-link" >The Galactic Emission Line Object Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/gunn-stryker-atlas-list' class="offcanvas__section-link" >Gunn-Stryker Atlas list</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/interstellar-extinction-curves' class="offcanvas__section-link" >Interstellar Extinction Curves</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/jacoby-hunter-christian-atlas' class="offcanvas__section-link" >Jacoby-Hunter-Christian Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/the-kinney-calzetti-spetral-atlas' class="offcanvas__section-link" >The Kinney-Calzetti Spectral Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/kinney-models' class="offcanvas__section-link" >Kinney Models</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/kurucz-1993-models' class="offcanvas__section-link" >Kurucz 1993 Models</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/non-stellar-spectra' class="offcanvas__section-link" >Non-Stellar Spectra</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/novae-models' class="offcanvas__section-link" >Novae Models</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/phoenix-models-available-in-synphot' class="offcanvas__section-link" >Phoenix Models available in Synphot</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/planetary-nebula-spectra' class="offcanvas__section-link" >Planetary Nebula Spectra</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/pickles-atlas' class="offcanvas__section-link" >Pickles Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/simple-stellar-population-atlas' class="offcanvas__section-link" >Simple Stellar Population Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/solar-system-objects-spectra' class="offcanvas__section-link" >Solar System Objects Spectra</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/swire-galaxies' class="offcanvas__section-link" >SWIRE Galaxies</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/the-trds-brown-atlas' class="offcanvas__section-link" >The TRDS Brown Atlas</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/trds-brown19-spectra-of-agns' class="offcanvas__section-link" >TRDS Brown19 Spectra of AGNs</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/modewave-data' class="offcanvas__section-link" >Modewave Data</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/documentation' class="offcanvas__section-link" 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section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Science_Operations_Design_Reference_Mission_-SODRM-_69_section" class="offcanvas__list" data-level="5" aria-labelledby="Science_Operations_Design_Reference_Mission_-SODRM-_69_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/jwst/about-jwst/history/science-operations-design-reference-mission-sodrm/solar-system-programs' class="offcanvas__section-link" >Solar System Programs</a></li><li class="offcanvas__item noChildren"><a href='/jwst/about-jwst/history/science-operations-design-reference-mission-sodrm/exoplanet-programs' class="offcanvas__section-link" >Exoplanet Programs</a></li><li class="offcanvas__item noChildren"><a href='/jwst/about-jwst/history/science-operations-design-reference-mission-sodrm/galactic-programs' class="offcanvas__section-link" >Galactic Programs</a></li><li class="offcanvas__item noChildren"><a 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href='/jwst/about-jwst/history/science-operations-design-reference-mission-sodrm/statistical-summary' class="offcanvas__section-link" >Statistical Summary</a></li></ul></li></ul></li><li class="offcanvas__item noChildren"><a href='/jwst/about-jwst/stsci-and-jwst' class="offcanvas__section-link" >STScI and JWST</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/jwst/about-jwst/science-themes' class="offcanvas__section-link" >Science Themes</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/jwst/news-events' class="offcanvas__section-link" >News & Events</a><button class="offcanvas__section-toggle" id="News_and_Events_70_control" type="button" aria-label="News and Events submenu" aria-controls="News_and_Events_70_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close 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