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4 Laser Guide Star Facility | ESO
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href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/vtl-test-cameras/"> VLT Test Cameras </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/visir/"> VISIR </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/x-shooter/"> X-shooter </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/paranal-observatory/vlt/vlt-names/"> VLT Unit Telescopes Names <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-288" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-names/antu/"> Antu </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-names/kueyen/"> Kueyen </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-names/melipal/"> Melipal </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-names/yepun/"> Yepun </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/paranal-observatory/vlt/vlti/"> VLT Interferometer <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-293" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/gravity+/"> GRAVITY+ </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/gravity/"> GRAVITY </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/matisse/"> MATISSE </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/naomi/"> NAOMI </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/pionier/"> PIONIER </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/amber/"> AMBER </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/midi/"> MIDI </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/vlt-instr/vinci/"> VINCI </a></li></ul></li><li class=""><a href="/public/teles-instr/paranal-observatory/vlt/auxiliarytelescopes/"> Auxiliary Telescopes </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/paranal-observatory/surveytelescopes/"> Survey Telescopes <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-303" class="submenu-aim sublevel"><li class="submenu"><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vista/"> VISTA <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-304" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vista/mirror/"> The VISTA mirror </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vista/camera/"> VIRCAM </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vista/4most/"> 4MOST </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vista/surveys/"> The VISTA surveys </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vista/consortium/"> The VISTA consortium </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vst/"> VST <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-310" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vst/mirror/"> The VST mirrors </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vst/camera/"> OmegaCAM </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/surveytelescopes/vst/surveys/"> The VST surveys </a></li></ul></li></ul></li><li class=""><a href="/public/teles-instr/paranal-observatory/speculoos/"> SPECULOOS </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/ngts/"> NGTS </a></li><li class=""><a href="/public/teles-instr/paranal-observatory/ctao/"> Cherenkov Telescope Array Observatory </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/"> La Silla Observatory <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-317" class="submenu-aim sublevel"><li class="submenu"><a href="/public/teles-instr/lasilla/swedish/"> Swedish–ESO Submillimetre Telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-318" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/swedish/simba/"> SIMBA </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/ntt/"> New Technology Telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-320" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/ntt/efosc2/"> EFOSC2 </a></li><li class=""><a href="/public/teles-instr/lasilla/ntt/emmi/"> EMMI </a></li><li class=""><a href="/public/teles-instr/lasilla/ntt/irspec/"> IRSPEC </a></li><li class=""><a href="/public/teles-instr/lasilla/ntt/sofi/"> SOFI </a></li><li class=""><a href="/public/teles-instr/lasilla/ntt/soxs/"> SOXS </a></li><li class=""><a href="/public/teles-instr/lasilla/ntt/susi2/"> SUSI and SUSI2 </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/36/"> ESO 3.6-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-327" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/36/adonis/"> ADONIS </a></li><li class=""><a href="/public/teles-instr/lasilla/36/caspec/"> CASPEC </a></li><li class=""><a href="/public/teles-instr/lasilla/36/irspec/"> IRSPEC </a></li><li class=""><a href="/public/teles-instr/lasilla/36/harps/"> HARPS </a></li><li class=""><a href="/public/teles-instr/lasilla/36/mefos/"> MEFOS </a></li><li class=""><a href="/public/teles-instr/lasilla/36/nirps/"> NIRPS </a></li><li class=""><a href="/public/teles-instr/lasilla/36/optopus/"> OPTOPUS </a></li><li class=""><a href="/public/teles-instr/lasilla/36/timmi2/"> TIMMI/2 </a></li><li class=""><a href="/public/teles-instr/lasilla/36/36-infrared-photometer-spectrophotometer/"> Infrared Photometer/Spectrophotometer </a></li><li class=""><a href="/public/teles-instr/lasilla/36/36-standard-photometer/"> Standard Photometer </a></li><li class=""><a href="/public/teles-instr/lasilla/36/infrared-specklegraph/"> Infrared Specklegraph </a></li><li class=""><a href="/public/teles-instr/lasilla/36/infrared-speckle-interferometer/"> Infrared Speckle Interferometer </a></li><li class=""><a href="/public/teles-instr/lasilla/36/efosc/"> EFOSC </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/mpg22/"> MPG/ESO 2.2-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-341" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/mpg22/feros/"> FEROS </a></li><li class=""><a href="/public/teles-instr/lasilla/mpg22/grond/"> GROND </a></li><li class=""><a href="/public/teles-instr/lasilla/mpg22/irac2/"> IRAC & IRAC2 </a></li><li class=""><a href="/public/teles-instr/lasilla/mpg22/pisco/"> PISCO </a></li><li class=""><a href="/public/teles-instr/lasilla/mpg22/wfi/"> WFI </a></li><li class=""><a href="/public/teles-instr/lasilla/mpg22/infrared-photometer-spectrophotometer/"> Infrared Photometer/Spectrophotometer </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/swiss/"> Swiss 1.2-metre Leonhard Euler Telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-348" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/swiss/coralie/"> CORALIE </a></li></ul></li><li class=""><a href="/public/teles-instr/lasilla/rem/"> Rapid Eye Mount telescope </a></li><li class=""><a href="/public/teles-instr/lasilla/trappist/"> TRAnsiting Planets and PlanetesImals Small Telescope–South </a></li><li class="submenu"><a href="/public/teles-instr/lasilla/danish154/"> Danish 1.54-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-352" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/danish154/coravel/"> CORAVEL </a></li><li class=""><a href="/public/teles-instr/lasilla/danish154/dfosc/"> DFOSC </a></li><li class=""><a href="/public/teles-instr/lasilla/danish154/ccd/"> CCD camera </a></li><li class=""><a href="/public/teles-instr/lasilla/danish154/hb-photometer/"> Hβ Photometer </a></li><li class=""><a href="/public/teles-instr/lasilla/danish154/two-channel-photometer/"> Two-Channel Photometer </a></li><li class=""><a href="/public/teles-instr/lasilla/danish154/four-channel-photometer/"> Four-Channel Photometer </a></li><li class=""><a href="/public/teles-instr/lasilla/danish154/six-channel-photometer/"> Six-Channel uvby-Hβ Photometer </a></li></ul></li><li class=""><a href="/public/teles-instr/lasilla/tarot/"> Télescope à Action Rapide pour les Objets Transitoires </a></li><li class=""><a href="/public/teles-instr/lasilla/1mschmidt/"> ESO 1-metre Schmidt telescope </a></li><li class="submenu"><a href="/public/teles-instr/lasilla/152metre/"> ESO 1.52-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-362" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/152metre/bandc/"> Boller and Chivens Spectrograph </a></li><li class=""><a href="/public/teles-instr/lasilla/152metre/coude/"> Coudé Spectrograph </a></li><li class=""><a href="/public/teles-instr/lasilla/152metre/echelec/"> ECHELEC </a></li><li class=""><a href="/public/teles-instr/lasilla/152metre/rv-cass-spectrograph/"> RV Cass Spectrograph </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/1metre/"> ESO 1-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-367" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/1metre/fideos/"> FIDEOS </a></li><li class=""><a href="/public/teles-instr/lasilla/1metre/infrared-photometer/"> Infrared Photometer </a></li><li class=""><a href="/public/teles-instr/lasilla/1metre/single-channel-photometer/"> Single-Channel Photometer </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/05metre/"> ESO 0.5-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-371" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/05metre/single-channel-photometer/"> Single-Channel Photometer </a></li><li class=""><a href="/public/teles-instr/lasilla/05metre/double-channel-photometer/"> Double-Channel Photometer </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/coude/"> Coudé Auxiliary Telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-374" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/coude/ces/"> CES </a></li></ul></li><li class=""><a href="/public/teles-instr/lasilla/marly/"> MarLy 1-metre telescope </a></li><li class="submenu"><a href="/public/teles-instr/lasilla/09metre/"> Dutch 0.9-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-377" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/09metre/walraven/"> Walraven Photometer </a></li></ul></li><li class=""><a href="/public/teles-instr/lasilla/t70/"> Swiss T70 telescope </a></li><li class="submenu"><a href="/public/teles-instr/lasilla/bochum/"> Bochum 0.61-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-380" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/bochum/bochum-scanner/"> Bochum Scanner </a></li><li class=""><a href="/public/teles-instr/lasilla/bochum/bochum-photometer/"> Bochum Photometer </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/lasilla/danish05/"> Danish 0.5-metre telescope <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-383" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/lasilla/danish05/danish-two-channel-hb-photometer/"> Two-Channel Hβ Photometer </a></li><li class=""><a href="/public/teles-instr/lasilla/danish05/danish-four-channel-uvby-photometer/"> Four-Channel uvby Photometer </a></li><li class=""><a href="/public/teles-instr/lasilla/danish05/danish-six-channel-uvby-hb-photometer/"> Six-Channel uvby–Hβ Photometer </a></li></ul></li><li class=""><a href="/public/teles-instr/lasilla/gpo/"> Grand Prisme Objectif telescope </a></li><li class=""><a href="/public/teles-instr/lasilla/swiss04/"> Swiss 0.4-metre telescope </a></li><li class=""><a href="/public/teles-instr/lasilla/marseille/"> Marseille 0.36-metre telescope </a></li><li class=""><a href="/public/teles-instr/lasilla/grb/"> GRB Monitoring System </a></li><li class=""><a href="/public/teles-instr/lasilla/mascara/"> MASCARA </a></li><li class=""><a href="/public/teles-instr/lasilla/blackgem/"> BlackGEM </a></li><li class=""><a href="/public/teles-instr/lasilla/extra/"> ExTrA </a></li><li class=""><a href="/public/teles-instr/lasilla/test-bed/"> Test-Bed Telescope </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/apex/"> APEX <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-395" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/apex/apex-2a/"> APEX–2A </a></li><li class=""><a href="/public/teles-instr/apex/artemis/"> ArTéMiS </a></li><li class=""><a href="/public/teles-instr/apex/aszca/"> ASZCa </a></li><li class=""><a href="/public/teles-instr/apex/champ-plus/"> CHAMP+ </a></li><li class=""><a href="/public/teles-instr/apex/concerto/"> CONCERTO </a></li><li class=""><a href="/public/teles-instr/apex/flash/"> FLASH </a></li><li class=""><a href="/public/teles-instr/apex/flash-plus/"> FLASH+ </a></li><li class=""><a href="/public/teles-instr/apex/laboca/"> LABOCA </a></li><li class=""><a href="/public/teles-instr/apex/mpi_11thz/"> MPI_1.1THz </a></li><li class=""><a href="/public/teles-instr/apex/p-artemis/"> P-ArTéMiS </a></li><li class=""><a href="/public/teles-instr/apex/pi230/"> PI230 </a></li><li class=""><a href="/public/teles-instr/apex/polka/"> PolKa </a></li><li class=""><a href="/public/teles-instr/apex/saboca/"> SABOCA </a></li><li class=""><a href="/public/teles-instr/apex/sepia/"> SEPIA </a></li><li class=""><a href="/public/teles-instr/apex/shefi/"> SHeFI </a></li></ul></li><li class="submenu"><a href="/public/teles-instr/alma/"> ALMA <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-411" class="submenu-aim sublevel"><li class=""><a href="/public/teles-instr/alma/antennas/"> Antennas 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href="#"> Black Holes <span class="desktop-children topmenu-arrow fa fa-angle-right"></span></a><span class="mobile-children"><span class="fa fa-angle-down"></span></span><ul id="submenu-aim-430" class="submenu-aim sublevel"><li class=""><a href="https://www.eso.org/public/science/event-horizon/"> First image of a black hole </a></li><li class=""><a href="https://www.eso.org/public/science/EHT-MilkyWay/"> First image of the Milky Way central black hole </a></li><li class=""><a href="https://www.eso.org/public/science/gc/"> More about the black hole at the galactic centre </a></li></ul></li><li class=""><a href="/public/science/grb/"> Gamma-Ray Bursts </a></li><li class=""><a href="/public/science/archive/"> Science Archive </a></li> </ul> </div> </div> </li> <li><a href="/public/events/">Events<span class="fa fa-angle-down level0-children-arrows"></span></a> <span class="mobile-children"> <span class="fa fa-angle-down"></span> </span> <div class="level1-wrapper"> <div class="level1"> 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href="/public/"> <div data-spy="affix" class="affix"> <div class="sprites-esologo"></div> <span>European<br>Southern<br>Observatory</span> </div> </a> </div> <div class="container " id="body"> <div class="row no-page"> <div class="col-md-12"> </div> </div> <div class="row page"> <div class="col-md-12 one-column"> <div id="edit-info-block"> <div id="page-edit-success" class="alert alert-success alert-dismissible" role="alert" style="display: none"> <button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">×</span></button> Page saved successfully </div> <div id="page-edit-failure" class="alert alert-danger alert-dismissible" role="alert" style="display: none"> <button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">×</span></button> Couldn't save page :( Please try again. </div> </div> <div class='page-content'> <div id="editable-content"> <h1>4 Laser Guide Star Facility</h1> <h2>Four new stars to defeat atmospheric turbulence</h2> <p><a href="/public/images/eso1613a/"><img src="/public/archives/static/teles-instr/vlt/images/eso1613a_pano.jpg" border="0" alt="eso1613a.jpg" width="970" height="264" style="border: 0px;"></a></p> <p><a href="/public/images/potw1225a/"><img src="/public/archives/images/potwmedium/potw1225a.jpg" border="0" alt="potw1225a.jpg" width="220" height="140" style="padding: 10px 20px 10px 0px; float: left; border: 0px;"></a>April 2016 saw the arrival of four new stars above the Paranal skies. After years of development, ESO has completed the installation of the 4 Laser Guide Star Facility or 4LGSF, a new subsystem of the <a href="/public/teles-instr/technology/adaptive_optics/">Adaptive Optics Facility (AOF)</a> at the <a href="/public/teles-instr/paranal/">Very Large Telescope</a> (VLT).</p> <p>The 4LGSF complements the Laser Guide Star Facility (LGSF). Instead of one laser, the 4LGSF sends four laser beams into the skies to produce four artificial stars by exciting sodium atoms located in the atmosphere at an altitude of 90 kilometres. Each laser delivers 22 watts of power — about 4000 times the maximum allowed for a laser pointer — in a beam with a diameter of 30 centimetres.</p> <p><a href="/public/images/eso1613d/"><img src="/public/archives/images/potwmedium/eso1613d.jpg" border="0" alt="eso1613d.jpg" width="220" height="140" style="padding: 10px 0px 10px 20px; float: right; border: 0px;"></a>Why is this new facility so important? This upgrade is necessary to support the new era of instruments at the Paranal Observatory, including <a href="/public/teles-instr/vlt/vlt-instr/hawk-i/">HAWK-I</a> (with GRAAL) and <a href="/public/teles-instr/vlt/vlt-instr/muse/">MUSE</a> (with <a href="/public/announcements/ann16025/">GALACSI</a>). In comparison to the LGSF, the 4LGSF is more stable, and will require less preventative maintenance and preparation times for observing runs will be shorter. It will also be the best laboratory to test devices for the <a href="/public/teles-instr/elt/">ELT</a>, which will have a similar adaptive optics system. The LGSF will continue to support <a href="/public/teles-instr/vlt/vlt-instr/sinfoni/">SINFONI</a>, the instrument mounted at the Cassegrain focal station of UT4, as SINFONI was designed to work with only one laser, on the same axis of the telescope.</p> <p dir="ltr">So, how do the lasers help to correct the images? The biggest barrier between ground-based telescopes and the stars is the Earth’s atmosphere. <a href="https://en.wikipedia.org/wiki/Astronomical_seeing" target="_blank">Atmospheric turbulence</a> causes a romantic but undesired effect in astronomy: twinkling stars, which result in blurred images.</p> <p>Adaptive optics (AO) solves this problem by combining the latest technologies to correct for distortions introduced by the atmosphere. To do this, the AO system needs the light from a sufficiently bright star that is close to the target in the sky as a reference, and for many targets there are no suitable stars close by.</p> <p><a href="/public/images/eso1613i/"><img src="/public/archives/images/potwmedium/eso1613i.jpg" border="0" alt="eso1613i.jpg" width="220" height="140" style="padding: 10px 20px 10px 0px; float: left; border: 0px;"></a>And this is where the lasers come in. Lasers can excite sodium atoms in the mesosphere, which is located 90–110 kilometres above the Earth’s surface. The fluorescent light that is emitted by the sodium atoms and collected by the telescope is affected by the atmosphere in the same way as the light emitted by real stars is. So, the fluorescent light from the sodium atoms can be used by the adaptive optics system to measure and compensate for the distortions introduced by the atmosphere.</p> <p>ESO and several European institutes and industries, including TOPTICA, Germany; TNO, the Netherlands; MPB Communications, Canada; Optec, Italy; Astrel, Italy; and Laseroptik, Germany and INAF–Osservatorio di Roma, have made significant contributions to the project. The new 4LGSF is based on several new technologies. One of these is fibre Raman laser technology, which was developed by ESO and transferred to industry, resulting in a Raman fibre amplifier laser that is lighter, more rugged, and represents a breakthrough in size and stability.</p> <p>All the operations at the 4LGSF will follow a protocol to avoid any risk to aircraft. The laser system is equipped with an automatic aircraft avoidance system that shuts down the lasers if an aircraft ventures too close to the beams.</p> <h3>Links:</h3> <ul> <li><a href="/public/news/archive/search/?published_until_year=0&published_until_day=0&description=&title=&instruments=74&subject_name=&published_since_day=0&published_since_month=0&published_until_month=0&id=&published_since_year=0">Press releaes with the instrument</a>.</li> </ul> </div> </div> </div> </div> </div> <!-- #body --> <div class="row footernote"> <div class="col-xs-12 col-md-3"> <a href="mailto:information@eso.org">Send us your comments!</a> </div> <div class="col-xs-12 col-md-3"> <a href="/public/outreach/newsletters/esonews/">Subscribe to receive news from ESO in your language</a> </div> <div class="col-xs-12 col-md-3"> <a href="https://www.cdn77.com">Accelerated by CDN77</a> </div> <div class="col-xs-12 col-md-3"> <a href="/public/about-eso/privacy/">Terms & Conditions</a> </div> </div> <link href="/public/archives/djp/css/extras.d3e54451ebbb.css" rel="stylesheet" type="text/css" /> <script type="text/javascript">var MEDIA_URL = "/public/archives/"</script> <script type="text/javascript" src="/public/archives/djp/js/main.86aaf133ddd1.js" charset="utf-8"></script> </div> <!-- content --> <div id="social-share" class="hidden-print"> <div class="link facebook" data-toggle="tooltip" data-placement="right" title="Share on Facebook"> <a href="https://www.facebook.com/sharer/sharer.php?u=https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/4lgsf/" target="_blank" rel="noopener noreferrer"><i class="fa-brands fa-facebook-f" aria-hidden="true"></i></a> </div> <div class="link twitter" data-toggle="tooltip" data-placement="right" title="Share on X/Twitter"> <a href="https://twitter.com/intent/tweet?url=https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/4lgsf/&text=4 Laser Guide Star Facility&via=ESO" target="_blank" rel="noopener noreferrer"><i class="fa-brands fa-x-twitter"></i><!-- <i class="fa fa-twitter" aria-hidden="true"> --></i></a> </div> <div class="link pinterest" data-toggle="tooltip" data-placement="right" title="Share on Pinterest"> <a href="https://pinterest.com/pin/create/button/?url=https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/4lgsf/&media=&description=4 Laser Guide Star Facility" target="_blank" rel="noopener noreferrer"><i class="fa-brands fa-pinterest-p" aria-hidden="true"></i></a> </div> <div class="link print" data-toggle="tooltip" data-placement="right" title="Print"> <a href="javascript:window.print()" target="_blank" rel="noopener noreferrer"><i class="fa fa-print" aria-hidden="true"></i></a> </div> <div class="link email" data-toggle="tooltip" data-placement="right" title="Share by email"> <a href="mailto:%20?subject=ESO — 4 Laser Guide Star Facility&body=https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/4lgsf/" target="_blank" rel="noopener noreferrer"><i class="fa-regular fa-envelope" aria-hidden="true"></i></a> </div> </div> <script> $('[data-toggle="tooltip"]').tooltip(); </script> <input type='hidden' name='csrfmiddlewaretoken' value='oW5CUJWIVOb4lwJg6WnfHHoyExBR1NrQtlxrZaCjizOaQCMBbVFnPtuuUfN9Hz4p' /> </body> </html>