The Imaging Performance of the Hubble Space Telescope

<!DOCTYPE html>     <html class="no-js" lang="en">  <head> <title>The Imaging Performance of the Hubble Space Telescope - NASA/ADS</title>  <link rel="apple-touch-icon" sizes="180x180" href="//styles/favicon/apple-touch-icon.png" /> <link rel="icon" type="image/png" sizes="32x32" href="//styles/favicon/favicon-32x32.png" /> <link rel="icon" type="image/png" sizes="16x16" href="//styles/favicon/favicon-16x16.png" /> <link rel="manifest" href="//styles/favicon/site.webmanifest" /> <link rel="mask-icon" href="//styles/favicon/safari-pinned-tab.svg" color="#5bbad5" /> <meta name="apple-mobile-web-app-title" content="NASA ADS" /> <meta name="application-name" content="NASA ADS" /> <meta name="msapplication-TileColor" content="#ffc40d" /> <meta name="theme-color" content="#ffffff" />  <link rel="stylesheet" href="/styles/css/styles.css"> <meta name="robots" content="noarchive"> <link rel="canonical" href="http://ui.adsabs.harvard.edu/abs/1991ApJ...369L..21B/abstract"/> <meta name="description" content="Problems with the HST instantaneous imaging performance and pointing performance are discussed. Optical tests have clearly demonstrated that the HST suffers from spherical aberration. The top level specification was that 70 percent of the energy be focused in a 0.1 in. radius, but the present, and close to optimum, focus setting gives only about 16 percent. The pointing control system also is having problems with the results that the spacecraft achieves a stability of about 0.007 rms in quiescent periods, falling short of specification which requires that such performance be maintained for 24 hr. The finite guidance sensors are not guiding well on faint stars. There is a loss of sky coverage at high Galactic latitude, especially for the Wide-Field/Planetary Camera. 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There is a loss of sky coverage at high Galactic latitude, especially for the Wide-Field/Planetary Camera. The consequences of these defects for the scientific program are examined."> <meta property="og:url" content="https://ui.adsabs.harvard.edu/abs/1991ApJ...369L..21B/abstract"> <meta property="og:image" content="https://ui.adsabs.harvard.edu/styles/img/transparent_logo.svg"> <meta property="article:published_time" content="03/1991"> <meta property="article:author" content="Burrows, Christopher J."> <meta property="article:author" content="Holtzman, Jon A."> <meta property="article:author" content="Faber, S. M."> <meta property="article:author" content="Bely, Pierre Y."> <meta property="article:author" content="Hasan, Hashima"> <meta property="article:author" content="Lynds, C. 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There is a loss of sky coverage at high Galactic latitude, especially for the Wide-Field/Planetary Camera. 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<li class="author"><a href="/search/?q=author%3A%22Holtzman%2C+Jon+A.%22">Holtzman, Jon A.</a> </li>; <li class="author"><a href="/search/?q=author%3A%22Faber%2C+S.+M.%22">Faber, S. M.</a> </li>; <li class="author"><a href="/search/?q=author%3A%22Bely%2C+Pierre+Y.%22">Bely, Pierre Y.</a> </li>; <li class="author"><a href="/search/?q=author%3A%22Hasan%2C+Hashima%22">Hasan, Hashima</a> </li>; <li class="author"><a href="/search/?q=author%3A%22Lynds%2C+C.+R.%22">Lynds, C. R.</a> </li>; <li class="author"><a href="/search/?q=author%3A%22Schroeder%2C+Daniel%22">Schroeder, Daniel</a> </li> </ul> </div> <div class="s-abstract-text"> <h4 class="sr-only">Abstract</h4> <p> Problems with the HST instantaneous imaging performance and pointing performance are discussed. Optical tests have clearly demonstrated that the HST suffers from spherical aberration. The top level specification was that 70 percent of the energy be focused in a 0.1 in. radius, but the present, and close to optimum, focus setting gives only about 16 percent. The pointing control system also is having problems with the results that the spacecraft achieves a stability of about 0.007 rms in quiescent periods, falling short of specification which requires that such performance be maintained for 24 hr. The finite guidance sensors are not guiding well on faint stars. There is a loss of sky coverage at high Galactic latitude, especially for the Wide-Field/Planetary Camera. The consequences of these defects for the scientific program are examined. </p> </div> <br> <dl class="s-abstract-dl-horizontal"> <dt>Publication:</dt> <dd> <div id="article-publication">The Astrophysical Journal</div> </dd> <dt>Pub Date:</dt> <dd>March 1991</dd> <dt>DOI:</dt> <dd> <span> <a href="/link_gateway/1991ApJ...369L..21B/doi:10.1086/185950" target="_blank" rel="noopener">10.1086/185950</a> <i class="fa fa-external-link"></i> </span> </dd> <dt>Bibcode:</dt> <dd> <a href="/abs/1991ApJ...369L..21B/abstract"> 1991ApJ...369L..21B </a> <i class="icon-help" title="The bibcode is assigned by the ADS as a unique identifier for the paper."></i> </dd> <dt>Keywords:</dt> <dd> <ul class="list-inline"> <li>Hubble Space Telescope;</li> <li>Mirrors;</li> <li>Pointing Control Systems;</li> <li>Spaceborne Photography;</li> <li>Aberration;</li> <li>Asphericity;</li> <li>Astronomical Photometry;</li> <li>Diffraction Limited Cameras;</li> <li>Astronomy;</li> <li>ANALYTICAL METHODS;</li> <li>IMAGE PROCESSING;</li> <li>INSTRUMENTS;</li> <li>NUMERICAL METHODS;</li> <li>PHOTOMETRY;</li> <li>SKY PHOTOGRAPHS;</li> <li>ULTRAVIOLET: GENERAL</li> </ul> </dd> </dl> </article> </div> <div data-widget="ShowCitations"></div> <div data-widget="ShowReferences"></div> <div data-widget="ShowCoreads"></div> <div data-widget="ShowSimilar"></div> <div data-widget="ShowTableofcontents"></div> <div data-widget="ShowGraphics"></div> <div data-widget="ShowExportcitation" data-origin="abstract"></div> <div data-widget="ShowMetrics" data-allow-redirect="false"></div> <div data-widget="MetaTagsWidget"></div> </div> </div> </div> <div class="s-right-col-container col-xs-12 col-sm-12 col-md-3 col-lg-2 s-right-column" id="right-col-container" > <div data-widget="ShowResources"> <div data-reactroot="" class="s-right-col-widget-container" style="padding: 10px" > <div> <div class="resources__container"> <div class="resources__full__list"> <div class="resources__header__row"> <i class="fa fa-file-text-o" 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// Add class "autocomplete-active": x[currentFocus].classList.add("autocomplete-active"); } function removeActive(x) { // Remove the "active" class from all autocomplete items: for (var i = 0; i < x.length; i++) { x[i].classList.remove("autocomplete-active"); } } function closeAllLists(elmnt) { // Close all autocomplete lists in the document, except the one passed as an argument: var x = document.getElementsByClassName("autocomplete-items"); for (var i = 0; i < x.length; i++) { if (elmnt != x[i] && elmnt != searchBox) { x[i].parentNode.removeChild(x[i]); } } } // Any other clicks in the document: document.addEventListener("click", function (e) { closeAllLists(e.target); }); } var autoList = [ { value: 'author:""', label: 'Author', match: 'author:"' }, { value: 'author:"^"', label: 'First Author', match: 'first author' }, { value: 'author:"^"', label: 'First Author', match: 'author:"^' }, { value: 'bibcode:""', label: 'Bibcode', desc: 'e.g. bibcode:1989ApJ...342L..71R', match: 'bibcode:"' }, { value: 'bibstem:""', label: 'Publication', desc: 'e.g. bibstem:ApJ', match: 'bibstem:"' }, { value: 'bibstem:""', label: 'Publication', desc: 'e.g. bibstem:ApJ', match: 'publication (bibstem)' }, { value: 'arXiv:', label: 'arXiv ID', match: 'arxiv:' }, { value: 'doi:', label: 'DOI', match: 'doi:' }, { value: 'full:""', label: 'Full text search', desc: 'title, abstract, and body', match: 'full:' }, { value: 'full:""', label: 'Full text search', desc: 'title, abstract, and body', match: 'fulltext' }, { value: 'full:""', label: 'Full text search', desc: 'title, abstract, and body', match: 'text' }, { value: 'year:', label: 'Year', match: 'year' }, { value: 'year:1999-2005', label: 'Year Range', desc: 'e.g. 1999-2005', match: 'year range' }, { value: 'aff:""', label: 'Affiliation', match: 'aff:' }, { value: 'abs:""', label: 'Search abstract + title + keywords', match: 'abs:' }, { value: 'database:astronomy', label: 'Limit to papers in the astronomy database', match: 'database:astronomy' }, { value: 'database:physics', label: 'Limit to papers in the physics database', match: 'database:physics' }, { value: 'title:""', label: 'Title', match: 'title:"' }, { value: 'orcid:', label: 'ORCiD identifier', match: 'orcid:' }, { value: 'object:', label: 'SIMBAD object (e.g. object:LMC)', match: 'object:' }, { value: 'property:refereed', label: 'Limit to refereed', desc: '(property:refereed)', match: 'refereed' }, { value: 'property:refereed', label: 'Limit to refereed', desc: '(property:refereed)', match: 'property:refereed' }, { value: 'property:notrefereed', label: 'Limit to non-refereed', desc: '(property:notrefereed)', match: 'property:notrefereed' }, { value: 'property:notrefereed', label: 'Limit to non-refereed', desc: '(property:notrefereed)', match: 'notrefereed' }, { value: 'property:eprint', label: 'Limit to eprints', desc: '(property:eprint)', match: 'eprint' }, { value: 'property:eprint', label: 'Limit to eprints', desc: '(property:eprint)', match: 'property:eprint' }, { value: 'property:openaccess', label: 'Limit to open access', desc: '(property:openaccess)', match: 'property:openaccess' }, { value: 'property:openaccess', label: 'Limit to open access', desc: '(property:openaccess)', match: 'openaccess' }, { value: 'doctype:software', label: 'Limit to software', desc: '(doctype:software)', match: 'software' }, { value: 'doctype:software', label: 'Limit to software', desc: '(doctype:software)', match: 'doctype:software' }, { value: 'property:inproceedings', label: 'Limit to papers in conference proceedings', desc: '(property:inproceedings)', match: 'proceedings' }, { value: 'property:inproceedings', label: 'Limit to papers in conference proceedings', desc: '(property:inproceedings)', match: 'property:inproceedings' }, { value: 'citations()', label: 'Citations', desc: 'Get papers citing your search result set', match: 'citations(' }, { value: 'references()', label: 'References', desc: 'Get papers referenced by your search result set', match: 'references(' }, { value: 'trending()', label: 'Trending', desc: 'Get papers most read by users who recently read your search result set', match: 'trending(' }, { value: 'reviews()', label: 'Review Articles', desc: 'Get most relevant papers that cite your search result set', match: 'reviews(' }, { value: 'useful()', label: 'Useful', desc: 'Get papers most frequently cited by your search result set', match: 'useful(' }, { value: 'similar()', label: 'Similar', desc: 'Get papers that have similar full text to your search result set', match: 'similar(' }, ]; // initiate the autocomplete function on the "q" element, and pass along the operators array as possible autocomplete values: inputBox = document.getElementById("q") if (inputBox) { inputBox.focus() // autofucs inputBox.setSelectionRange(inputBox.value.length, inputBox.value.length); // bring cursor to the end autocomplete(inputBox, autoList); } </script> <script> (function() { // turn off no-js if we have javascript document.documentElement.className = document.documentElement.className.replace("no-js", "js"); function getCookie(cname) { var name = cname + "="; var decodedCookie = decodeURIComponent(document.cookie); var ca = decodedCookie.split(';'); for (var i = 0; i < ca.length; i++) { var c = ca[i]; while (c.charAt(0) == ' ') { c = c.substring(1); } if (c.indexOf(name) == 0) { return c.substring(name.length, c.length); } } return ""; } (function() { // looks for the cookie, and sets true if its 'always' const coreCookie = getCookie('core') === 'always'; // only load bumblebee if we detect the core cookie and we are on abstract page if (coreCookie || (!(/^\/abs\//.test(document.location.pathname)) && !coreCookie)) { return; 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The Imaging Performance of the Hubble Space Telescope - NASA/ADS