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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 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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 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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 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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 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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 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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 </a></li><li class=""><a href="/public/teles-instr/alma/transporters/"> Transporters </a></li><li class=""><a href="/public/teles-instr/alma/interferometry/"> Interferometry </a></li><li class=""><a 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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"> <ul id="submenu-aim-436" class="submenu-aim"> <li class=""><a href="/public/events/press-evt/"> Press Events </a></li><li class="submenu"><a href="/public/events/special-evt/"> Special Events <span 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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><a class="anchor" name="Top"></a>FAQ ESO</h1> <ol> <li><a href="#1">What kind of advantages does membership of ESO bring?</a></li> <li><a href="#2">What is ESO's relationship with Chile?</a></li> <li><a href="#3">Do ESO observatories only see the southern skies?</a></li> <li><a href="#4">Is light pollution a serious problem for astronomical observations?</a></li> <li><a href="#5">How much do the Member States pay to run ESO annually?</a></li> <li><a href="#6">Is it possible to visit ESO? Can you tell me more about virtual tours of ESO sites?</a></li> <li><a href="#7">How can I work or volunteer at ESO?</a></li> <li><a href="#8">Can I use ESO videos and images?</a></li> <li><a href="#9">Does ESO offer educational material for teachers, students or the general public?</a></li> <li><a href="#10">Are the colours in the astronomical images real?</a></li> <li><a href="#11">Can you give a couple of examples of the latest discoveries made at ESO?</a></li> <li><a href="#12">How long is the average life-time of a telescope?</a></li> <li><a href="#13">How many proposals for observing time does ESO get?</a></li> <li><a href="#14">Why don't we always build the astronomical observatories on the highest mountains, so that the height of the atmosphere is less above the telescopes?</a></li> <li><a href="#15">What is the theoretical maximum resolution of a single telescope?</a></li> <li><a href="#16">What is the origin of the reddish or greenish glow in the sky that appears in night pictures and time lapse videos taken at exceptional sites such as ESO’s Paranal Observatory?</a></li> <li><a href="#17">Is it possible to visit any ESO sites other than the observatories?</a></li> <li><a href="#18">How can I receive the latest ESO news?</a></li> <li><a href="#19">Is it possible for our organisation to become an ESO partner in astronomy outreach?</a></li> <li><a href="#20">How can I subscribe/unsubscribe to The Messenger or notify you of a change of address?</a></li> <li><a href="#21">Is it possible to see a list of scientific publications based on ESO data?</a></li> <li><a href="#22">Is it possible to get data from the ESO science archive?</a></li> <li><a href="#23">Can non-scientists ask to point ESO telescopes to specific objects?</a></li> <li><a href="#24">Is it possible to buy or name a star?</a></li> </ol> <hr /> <h3><a class="anchor" name="1"></a><strong>Q:</strong> What kind of advantages does membership of ESO bring?</h3> <p><strong>A:</strong> The main advantage for the community of professional astronomers and astrophysicists of an ESO Member State is the availability of observing time on the most advanced ground-based telescopes in the world, as well as access to the southern sky from one of the best observing sites on Earth — the Atacama Desert. Moreover, ESO is the most suitable organisation for conducting mega-science projects in astronomy, and for fostering international astronomical collaborations.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="2"></a><strong>Q:</strong>What is ESO's relationship with Chile?</h3> <p><strong>A: </strong>ESO built its observatories in Chile because of the exceptional observing conditions to be found in the north of the country which are unequalled anywhere else in the southern hemisphere. There has been a long and fruitful collaboration between ESO and the host country, Chile, that is celebrating its 60th anniversary in late 2023. More details are available here: ESO & Chile (<a href="https://www.eso.org/public/about-eso/eso-and-chile/">English</a>) / ESO y Chile (<a href="https://www.eso.org/public/chile/about-eso/eso-and-chile/?lang">Español</a>).</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="3"></a><strong>Q:</strong> Do ESO observatories only see the southern skies?</h3> <p><strong>A:</strong> The region of the sky visible from the Earth changes with latitude. If we could stand at the South Pole, we would only see the southern sky. As we move north towards the equator, the pole goes down from the zenith to the horizon and a larger part of the northern sky becomes visible. ESO observatories are located at a latitude of about 23°S, making the northern sky theoretically visible up to 67°N. Thus 95% of the whole sky is visible from the ESO sites in Chile. As the telescopes cannot point down to the horizon, 87% of the whole sky can be observed by ESO telescopes.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="4"></a><strong>Q:</strong> Is light pollution a serious problem for astronomical observations?</h3> <p><strong>A:</strong> Yes it is, for optical astronomy. Only the brightest stars are visible from a city, whilst from very dark places like the ESO sites in Chile, it is even possible to see your shadow cast by the brightest stars on a clear moonless night. While visible light pollution does not disturb astronomical observations in other bands of the electromagnetic spectrum such as radio waves, radio astronomy can be affected by terrestrial signals emitted at the same frequencies as those detected by the telescopes.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="5"></a><strong>Q:</strong> How much do the Member States pay to run ESO annually?</h3> <p><strong>A:</strong> The <a href="http://www.eso.org/public/about-eso/memberstates/">ESO Member State contributions</a> totalled 192 million euros in 2021.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="6"></a><strong>Q:</strong> Is it possible to visit ESO? Can you tell me more about virtual tours of ESO sites?</h3> <p><strong>A:</strong> ESO's La Silla and Paranal Observatories in Chile offer regular scheduled public visits. Media visits to ESO Headquarters in Germany and to the observatories in Chile need to be arranged in advance. The ESO Supernova Planetarium and Visitor Centre, next to the ESO Headquarters in Garching, Germany, is open to the public. For more information, please see: <a href="http://www.eso.org/public/about-eso/visitors/index.html">http://www.eso.org/public/about-eso/visitors/index.html</a> and <a href="https://supernova.eso.org/">https://supernova.eso.org/</a>.</p> <p>Please note that virtual tours of our Paranal and La Silla Observatories are offered every month, in both English and Spanish. They take place on Saturdays. If you are interested in joining them, we encourage you to keep an eye on the ESO Facebook and Twitter (now X) channels, where we announce them a few days in advance.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="7"></a><strong>Q:</strong> How can I work or volunteer at ESO?</h3> <p><strong>A:</strong> To find out more about working at ESO, please see the <a href="https://recruitment.eso.org/">ESO Recruitment Portal</a>.</p> <p>Please note that ESO does not currently offer volunteering opportunities. For possible volunteering opportunities in science outreach, and in particular as a translator to contribute to sharing astronomy in multiple languages, you can reach out to the national members of the ESO Science Outreach Network (<a href="https://www.eso.org/public/outreach/partnerships/eson/%20">ESON</a>): <a href="https://www.eso.org/public/outreach/partnerships/translators/">https://www.eso.org/public/outreach/partnerships/translators/</a>.</p> <p>For opportunities at the ESO Supernova Planetarium & Visitor Centre, please visit this page: <a href="https://supernova.eso.org/join-us/">https://supernova.eso.org/join-us/</a>. </p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="8"></a><strong>Q:</strong> Can I use ESO videos and images?</h3> <p><strong>A:</strong> Yes. ESO <a href="https://www.eso.org/public/images/">images</a> and <a href="https://www.eso.org/public/videos/">videos</a> are released under the Creative Commons Attribution 4.0 International License for easy re-use. Read more about the use of ESO videos and images in our copyright notice: <a href="/public/outreach/copyright.html">http://www.eso.org/public/outreach/copyright.html</a></p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="9"></a><strong>Q:</strong> Does ESO offer educational material for teachers, students or the general public?</h3> <p><strong>A:</strong> You can find a list of downloadable ESO education and Public Outreach products at: <a href="http://www.eso.org/public/outreach/products/">http://www.eso.org/public/outreach/products/</a>. Some products can be ordered in printed form which is free for educators and the media. Please see <a href="http://www.eso.org/public/shop/freeorder/">http://www.eso.org/public/shop/freeorder/</a>. For more specific educational material, please see: <a href="http://www.eso.org/public/products/education/">http://www.eso.org/public/products/education/</a>.</p> <p>For more opportunities available for educators, please check: <a href="https://supernova.eso.org/education/">https://supernova.eso.org/education/</a>.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="10"></a><strong>Q:</strong> Are the colours in the astronomical images real?</h3> <p><strong>A:</strong> Unlike commercial digital cameras, the cameras on research telescopes take greyscale images through filters. These are the images used for scientific analysis. For presentation to the general public, observations through multiple individual filters are often combined to produce colour images. For observations made with visible light, we often try to match the colours that our eyes can see. However, often the light that is observed is invisible to our limited human vision, for example, infrared light, and has to be represented with a visible colour instead. Often the shortest wavelength is represented with blue and the longest with red and this choice of colours is called "chromatic". Observations through narrowband filters are usually assigned colours in "chromatic order", although sometimes the ordering is, for aesthetic purposes, not kept chromatic and this leads images known as "enhanced colour images".</p> <p><a href="#Top">Top</a></p> <h3><a class="anchor" name="11"></a><strong>Q: </strong>Can you give a couple of examples of the latest discoveries made at ESO?</h3> <p><strong>A: </strong>The list is long and we invite you to have a look at all the ESO <a href="/public/news/">press releases</a> and at the <a href="/public/science/top10.html">Top 10 ESO Discoveries</a>.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="12"></a><strong>Q: </strong>How long is the average life-time of a telescope?</h3> <p><strong>A: </strong>It depends very much on the project, its design, objectives and funding. For the whole of ESO’s existence, the most ambitious astronomical projects have demanded ever larger investments that cannot be afforded only by a single country. In order to “recover” such important investments, a facility should operate for at least a couple of decades at the forefront of astronomy, before the next generation of telescopes takes over. After that, the telescopes continue operating, typically with new instruments and often dedicated to specific observing programmes. This is the case with the ESO 3.6-metre telescope, commissioned in 1977. It was for many years the largest European telescope and one of the largest telescopes in the southern hemisphere. It is now home to the world’s foremost exoplanet hunter: HARPS (High Accuracy Radial velocity Planet Searcher).</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="13"></a><strong>Q: </strong>How many proposals for observing time does ESO get?</h3> <p><strong>A: </strong>Each year, about 2000 proposals are made for the use of ESO telescopes, requesting between four and six times more nights than are available. ESO is the most productive observatory in the world, which annually results in an impressive number of peer-reviewed publications: more than two every day of the year.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="14"></a><strong>Q: </strong>Why don't we always build the astronomical observatories on the highest mountains, so that the height of the atmosphere is less above the telescopes?</h3> <p><strong>A: </strong>The quality of an astronomical site does not necessarily always improve with altitude, as there can be many different meteorological factors involved. These include the stability of the atmosphere, which can, for example, be affected by the terrain and other local conditions. So, while higher altitudes are often good, they are not always better. More practically, at very high altitudes, such as on the 5000-metre Chajnantor plateau where ALMA is being constructed, environmental factors make it difficult to build and operate an observatory. At very high observatory sites, engines lose power in the reduced air pressure, materials must withstand extreme weather conditions, and the low pressure and lack of oxygen affect the human body. Therefore, real scientific benefits are needed to justify the challenges of building an observatory on a higher site.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="15"></a><strong>Q: </strong>What is the theoretical maximum resolution of a single telescope?</h3> <p><strong>A: </strong>For a single telescope, its resolution (the finest details it can distinguish) is limited by the diffraction of light as it passes through the telescope's aperture. The resolution is improved if the wavelength of the light gets shorter or the telescope diameter gets larger. Since the wavelength may be fixed by the kind of astrophysical observations that are needed, this is one reason why astronomers try to build larger telescopes. This fundamental limit on the sharpness of a telescope's vision is called the diffraction limit, and telescopes that reach it are diffraction-limited.</p> <p>The sharpness of a telescope's vision may be worse in practice than this ideal value. For example, at visible light wavelengths, atmospheric turbulence will further degrade the telescope resolution. Technology such as adaptive optics can allow telescopes to overcome atmospheric turbulence and approach diffraction-limited resolution.</p> <p>Telescope resolution can be measured by the angular size of the smallest details that can be distinguished. Objects separated by less than this angle are blurred together and cannot be separated. The angle, represented by the symbol θ (measured in radians), is related to the wavelength of the light, λ, and the telescope diameter D by θ≈λ/D. Small angles θ represent finer details and hence better resolution. For example, ESO’s optical and infrared Very Large Telescope on Cerro Paranal has Unit Telescopes with mirror diameters of 8.2 metres. At infrared wavelengths of about 2 micrometres, they have a diffraction-limited resolution of about 50 milliarcseconds (a little over ten millionths of a degree).</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="16"></a><strong>Q: </strong>What is the origin of the reddish or greenish glow in the sky that appears in night pictures and time lapse videos taken at exceptional sites such as ESO’s Paranal Observatory?</h3> <p><strong>A: </strong>In most cases, the diffuse red or green light is due to a natural faint glow of the atmosphere called airglow. This faint airglow is invisible to the naked eye, but it can be recorded photographically when using long exposure times. However, faint glows in photos and video footage can also be produced by a mix of other sources, both natural and artificial.</p> <p>Among the natural sources are: sunlight illuminating the high atmosphere a long time after sunset or before sunrise, moonlight from a tiny crescent or waning moon or the zodiacal light, which is sunlight scattered by interplanetary dust inside the Solar System.</p> <p>Moreover, even at exceptional sites such as ESO’s Paranal Observatory, clouds may occasionally appear. A very thin layer of high altitude clouds can produce a diffuse veil of light originating from the Sun and Moon.</p> <p>Besides these natural sources, artificial light can also contribute to the glow. Even from isolated sites such as Paranal Observatory, light pollution from very distant cities or mines can be spotted in long exposure pictures or videos. Fortunately it is a small effect, visible only along the horizon.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="18"></a><strong>Q:</strong> How can I receive the latest ESO news?</h3> <p><strong>A:</strong> The ESO Department of Communication offers journalists and the public a number of ways to keep up with the latest ESO news. For more information, please see <a href="http://www.eso.org/public/outreach/newsletters.html">http://www.eso.org/public/outreach/newsletters.html</a>. You can also follow ESO on <a href="http://www.facebook.com/pages/ESO-Astronomy/10867667494" target="_blank" rel="noopener">Facebook</a>, <a href="http://twitter.com/ESO_Observatory" target="_blank" rel="noopener">Twitter (now X)</a> and <a href="https://www.instagram.com/esoastronomy/?hl=en">instagram</a>, and you can even follow our <a href="https://www.eso.org/public/blog/">blog</a>.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="19"></a><strong>Q:</strong> Is it possible for our organisation to become an ESO partner in astronomy outreach?</h3> <p><strong>A:</strong> For more information about the opportunities available for collaborations, please see: Partnerships <a href="http://www.eso.org/public/outreach/partnerships.html">http://www.eso.org/public/outreach/partnerships.html</a>.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="20"></a><strong>Q:</strong> How can I subscribe/unsubscribe to <em>The Messenger</em> or notify you of a change of address?</h3> <p><strong>A:</strong> The Messenger is ESO’s journal for science and technology. Since mid 2023, the Messenger is a digital publication only, published twice a year. It's available for free download as a PDF and via the digital publishing platform Scribd. For more information, check: <a href="https://messenger.eso.org/">https://messenger.eso.org/</a>.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="21"></a><strong>Q:</strong> Is it possible to see a list of scientific publications based on ESO data?</h3> <p><strong>A:</strong> A list of scientific publications based on ESO data, as well as all the publications available in ESO's libraries can be found at: <a href="http://www.eso.org/sci/libraries/">http://www.eso.org/sci/libraries/</a>.</p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" style="background-image: url('img/anchor.gif');" name="22"></a><strong>Q:</strong> Is it possible to get data from the ESO science archive?</h3> <p><strong>A:</strong> Yes, for more information about the distribution of ESO science data, please see: Science Archive <a href="http://www.eso.org/public/science/archive.html">http://www.eso.org/public/science/archive.html</a>. </p> <p><small><a href="#Top">Top</a></small></p> <h3><a class="anchor" name="23"></a><strong>Q:</strong> Can non-scientists ask to point ESO telescopes to specific objects?</h3> <p><strong>A:</strong> Due to the limited amount of available observing time, ESO telescopes can generally only be used by professional astronomers. Nevertheless, the data collected is publicly available through the ESO archive.</p> <p><small><a href="#Top">Top</a></small></p> <h3><strong>Q:</strong> Is it possible to buy or name a star?</h3> <p><strong><a class="anchor" name="24"></a>:</strong> The International Astronomical Union is the internationally recognised authority for naming celestial bodies and surface features on them. Names are not sold, but assigned according to internationally accepted rules. For more information on this topic, please see: <a href="http://www.iau.org/public/buying_star_names/" target="_blank" rel="noopener">http://www.iau.org/public/buying_star_names/</a>.</p> <p><small><a href="#Top">Top</a></small></p> </div> </div> </div> </div> </div>  <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>  <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/about-eso/faq/faq-eso/" 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/about-eso/faq/faq-eso/&text=FAQ ESO&via=ESO" target="_blank" rel="noopener noreferrer"><i class="fa-brands fa-x-twitter"></i></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/about-eso/faq/faq-eso/&media=&description=FAQ ESO" 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 — FAQ ESO&body=https://www.eso.org/public/about-eso/faq/faq-eso/" 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='n3ap6Qvw2ZERJoEbuRTbyz8hpcaMQs9ebsCInsSAn8BxTn4DsMGmMqac7eALNZFD' /> </body> </html>

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