[{"command":"openDialog","selector":"#drupal-modal","settings":null,"data":"\u003Cdiv id=\u0022republish_modal_form\u0022\u003E\u003Cform class=\u0022modal-form-example-modal-form ecl-form\u0022 data-drupal-selector=\u0022modal-form-example-modal-form\u0022 action=\u0022\/en\/article\/modal\/9793\u0022 method=\u0022post\u0022 id=\u0022modal-form-example-modal-form\u0022 accept-charset=\u0022UTF-8\u0022\u003E\u003Cp\u003EHorizon articles can be republished for free under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence.\u003C\/p\u003E\n \u003Cp\u003EYou must give appropriate credit. We ask you to do this by:\u003Cbr \/\u003E\n 1) Using the original journalist\u0027s byline\u003Cbr \/\u003E\n 2) Linking back to our original story\u003Cbr \/\u003E\n 3) Using the following text in the footer: This article was originally published in \u003Ca href=\u0027#\u0027\u003EHorizon, the EU Research and Innovation magazine\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003ESee our full republication guidelines \u003Ca href=\u0027\/horizon-magazine\/republish-our-stories\u0027\u003Ehere\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003EHTML for this article, including the attribution and page view counter, is below:\u003C\/p\u003E\u003Cdiv class=\u0022js-form-item form-item js-form-type-textarea form-item-body-content js-form-item-body-content ecl-form-group ecl-form-group--text-area form-no-label ecl-u-mv-m\u0022\u003E\n \n\u003Cdiv\u003E\n \u003Ctextarea data-drupal-selector=\u0022edit-body-content\u0022 aria-describedby=\u0022edit-body-content--description\u0022 id=\u0022edit-body-content\u0022 name=\u0022body_content\u0022 rows=\u00225\u0022 cols=\u002260\u0022 class=\u0022form-textarea ecl-text-area\u0022\u003E\u003Ch2\u003ESearching the skies for the building blocks of life in the universe\u003C\/h2\u003E\u003Cp\u003ESince its 25 December 2021 launch aboard an Ariane 5 rocket from French Guiana and following 30 years in the making, the James Webb Space Telescope (JWST) is the Christmas Day gift to astronomers that keeps on giving.\u003C\/p\u003E\u003Cp\u003ELike many astronomers in Europe, Pierre-Olivier Lagage, an astrophysicist at the Paris-based French Alternative Energies and Atomic Energy Commission (CEA), has been preparing for JWST for years.\u003C\/p\u003E\u003Cp\u003EA joint project with NASA, the Canadian Space Agency (CSA) and the European Space Agency (ESA), JWST started beaming back its first images of the cosmos in July 2022 after arriving at its vantage point 1.5 million kilometres from the Earth and unfurling its distinctive giant sunshield.\u003C\/p\u003E\u003Cp\u003EA worthy successor to the iconic Hubble Space Telescope, the \u20ac10 billion JWST has big scientific goals. These include the study of the early universe shortly after the Big Bang, galaxies and star formation, black holes, our own solar system and the search for the building blocks of life in the universe.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EScientific goldmine\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\u2018An exoplanet is a planet orbiting a star other than the Sun,\u2019 Lagage said.\u003C\/p\u003E\u003Cp\u003ELagage is the principal investigator of the H2020-funded \u2018Exoplanet Atmosphere New Emission Transmission Spectra Analysis\u2019 or \u003Ca href=\u0022https:\/\/cordis.europa.eu\/project\/id\/776403\u0022\u003EExoplANETS A project\u003C\/a\u003E. He and his colleagues developed a data tool to exploit the wealth of existing spectroscopic data from \u003Ca href=\u0022https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2018\/08\/Exoplanet_mission_timeline\u0022\u003Eprevious missions\u003C\/a\u003E to study exoplanets.\u003C\/p\u003E\u003Cp\u003EFrom a standing start, exoplanet astronomy has discovered thousands of exoplanets in the past 20 years. Now JWST\u2019s spectroscopy instrumentation offers an unprecedented opportunity to study exoplanets for the chemical signatures of life in their atmosphere.\u003C\/p\u003E\u003Cp\u003ESpectroscopy of transiting exoplanets is one of the main techniques in exoplanet astronomy. When an orbiting planet moves in front of its star relative to the observer, the spectrum of light from the star changes as it passes through the planet\u2019s atmosphere. When the changes in the light are detected, they indicate the chemical composition of the planet\u2019s atmosphere and whether it is likely to support life or not.\u003C\/p\u003E\u003Cp\u003E\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003EIn the case of the TRAPPIST-1 planets, the mass of the planets is so small that the classical technique (of measuring the weight of planets) doesn\u2019t work.\r\n\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003EMartin Turbet, ESCAPE\u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\u003Cp\u003EThe Exoplanets A tool uses data analysis to enable astronomers to characterise a broad range of exoplanet atmospheres. Astronomers using JWST are likely to find this useful to help their own observations by indicating which information is likely to be useful, and what is likely to be noise.\u003C\/p\u003E\u003Cp\u003EOne drawback of spectroscopic observations is that while they are a goldmine of information, the signal is mixed up with a lot of noise. Useless information not related to the exoplanet\u2019s atmosphere can obscure the valuable data in the observation.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ESystematic noise\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EThis is because the signal created by the planetary atmosphere is tiny compared with the rest of the light coming from the star, according to Lagage. \u2018So, you have to develop tools to remove this systematic noise and get the right signal,\u2019 he said.\u003C\/p\u003E\u003Cp\u003EThe Exoplanets A project goes further. In order to model the atmosphere of an exoplanet, you also need to have a good understanding of its host star. To assist with this, the project created a database of the properties of stars with exoplanets. It was made with archived data from the \u003Ca href=\u0022https:\/\/www.esa.int\/Science_Exploration\/Space_Science\/XMM-Newton_overview\u0022\u003EESA\u2019s XMM-Newton\u003C\/a\u003E and \u003Ca href=\u0022https:\/\/www.esa.int\/Science_Exploration\/Space_Science\/Gaia_overview\u0022\u003EGaia space observatory\u003C\/a\u003E.\u003C\/p\u003E\u003Cp\u003E\u003Cfigure role=\u0022group\u0022\u003E\n\u003Cimg alt=\u0022This image shows the exoplanet HIP 65426 b in different bands of infrared light, as seen from the James Webb Space Telescope. Image Credit: NASA\/ESA\/CSA, A Carter (UCSC), the ERS 1386 team, and A. Pagan (STScI)\u0022 data-entity-type=\u0022file\u0022 data-entity-uuid=\u0022d292d43f-4ae8-4a7e-b248-35fec5e23d3a\u0022 src=\u0022\/sites\/default\/files\/hm\/IMCEUpload\/Body%20STSCI-J-p2022-HIP65426b-f-1528x1130-1.png\u0022\u003E\n\u003Cfigcaption class=\u0022tw-italic tw-mb-4\u0022\u003EThis image shows the exoplanet HIP 65426 b in different bands of infrared light, as seen from the James Webb Space Telescope. Image Credit: NASA\/ESA\/CSA, A Carter (UCSC), the ERS 1386 team, and A. Pagan (STScI)\u003C\/figcaption\u003E\n\u003C\/figure\u003E\n\u003C\/p\u003E\u003Cp\u003EJWST\u2019s initial exoplanet observations were of hot gas giant \u003Ca href=\u0022https:\/\/exoplanets.nasa.gov\/exoplanet-catalog\/5673\/wasp-39-b\/\u0022\u003Eplanet WASP-39b\u003C\/a\u003E, described as a \u2018hot Jupiter\u2019. It orbits a Sun-like star 700 light-years away. Last month, using spectroscopy, JWST made the \u003Ca href=\u0022https:\/\/www.nytimes.com\/2022\/08\/26\/science\/space\/webb-telescope-wasp-exoplanet.html\u0022\u003Efirst confirmed observation of carbon dioxide in an exoplanet\u003C\/a\u003E.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ECaught in a TRAPPIST-1\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EThe ESCAPE (Exploring Shortcuts for the Characterization of the Atmospheres of Planets similar to Earth) project has also been looking for shortcuts to help characterise the atmospheres of Earth-like exoplanets.\u003C\/p\u003E\u003Cp\u003EMartin Turbet, an astrophysicist at the \u003Ca href=\u0022https:\/\/www.cnrs.fr\/en\/cnrs\u0022\u003EFrench National Centre for Scientific Research (CNRS)\u003C\/a\u003E and principal investigator on \u003Ca href=\u0022https:\/\/cordis.europa.eu\/project\/id\/832738\u0022\u003Ethe H2020-funded ESCAPE project\u003C\/a\u003E, said that this required exploring novel observation techniques, using different ground- and space-based telescopes.\u003C\/p\u003E\u003Cp\u003EFor example, the astronomers have been developing new methods to calculate the density of the planets orbiting TRAPPIST-1, an ultra-cool red dwarf star around 40 light years from our solar system.\u003C\/p\u003E\u003Cp\u003EDiscovered initially in 2000, it was later announced in 2017 that the TRAPPIST-1 star hosts seven small exoplanets, orbiting in tight formation, at least some of which may be habitable.\u003C\/p\u003E\u003Cp\u003E\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003EWhat I am most interested in is the atmosphere of super-Earth and Earth-sized exoplanets.\r\n\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003EPierre-Olivier Lagage, Exoplanets A\u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\u003Cp\u003ETo calculate the density of a planet, you need to know its radius and mass. Sizing the planet can be done using spectroscopic observations. Mass can be calculated by observing the effect of the planet\u2019s gravitational pull on its host star.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EWeighing exoplanets\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\u2018This is the classical way to measure the weight of a planet,\u2019 said \u003Ca href=\u0022https:\/\/web.lmd.jussieu.fr\/~mturbet\/index.html\u0022\u003ETurbet\u003C\/a\u003E. \u2018But in the case of the TRAPPIST-1 planets, the mass of the planets is so small that the classical technique doesn\u2019t work.\u2019\u003C\/p\u003E\u003Cp\u003EHowever, the TRAPPIST-1 system is peculiar because the seven planets all orbit very close to each other and exert strong gravitational forces on each other, he said.\u003C\/p\u003E\u003Cp\u003EThis effects their orbits and means that they don\u2019t pass, or transit, in front of their host star at fixed time points.\u003C\/p\u003E\u003Cp\u003EMeasuring the deviations in these transit timings enabled the researchers to assess the strength of the gravitational forces between the planets and evaluate their masses, said Turbet.\u003C\/p\u003E\u003Cp\u003EThanks to this this technique, they say they are now able to make the most accurate predictions so far of \u003Ca href=\u0022https:\/\/iopscience.iop.org\/article\/10.3847\/PSJ\/abd022\u0022\u003Ethe water content of the seven known planets in the TRAPPIST-1 system\u003C\/a\u003E.\u003C\/p\u003E\u003Cp\u003EThe observations, and mass, density and water content calculations were made using ground-based telescopes \u2013 such as the SPECULOOS telescope at the European Southern Observatory (ESO) in Chile, space-telescopes, and novel theoretical work.\u003C\/p\u003E\u003Cp\u003ETurbet said that the JWST and the planned \u003Ca href=\u0022https:\/\/elt.eso.org\/\u0022\u003EExtremely Large Telescope\u003C\/a\u003E (ELT) could be able to detect potential signs of life, known as biomarkers, in exoplanet atmospheres.\u003C\/p\u003E\u003Cp\u003EHe cautioned, however, that these \u2018cannot be used as definitive proof that there is life on the planet\u2019. This is because recent work has shown that biomarkers, such as oxygen, can be formed without life.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EReflected starlight\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003ETurbet and his colleagues have also been investigating a newer spectroscopy technique, known as reflected light spectroscopy. Rather than analysing how a star\u2019s light changes as a planet passes in front of it, this method looks at how light from the star is reflected by the planet\u2019s atmosphere.\u003C\/p\u003E\u003Cp\u003EThe models of water content and planetary atmospheres will also assist observations from the JWST, Turbet said. They will enable astronomers to plan their observations to maximise the collection of data of genuine interest.\u003C\/p\u003E\u003Cp\u003EThat being said, exoplanet research isn\u2019t just about looking for alien life. Exoplanets could also provide us with information on the history of Earth and how its atmosphere developed, according to Lagage.\u003C\/p\u003E\u003Cp\u003E\u2018What I am most interested in is the atmosphere of super-Earth and Earth-sized exoplanets,\u2019 he said.\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EResearch in this article was funded via the EU\u0027s Marie Sk\u0142odowska-Curie Actions (MSCA). If you liked this article, please consider sharing it on social media.\u003C\/em\u003E\u003C\/p\u003E\u003C\/textarea\u003E\n\u003C\/div\u003E\n\n \u003Cdiv id=\u0022edit-body-content--description\u0022 class=\u0022ecl-help-block description\u0022\u003E\n Please copy the above code and embed it onto your website to republish.\n \u003C\/div\u003E\n \u003C\/div\u003E\n\u003Cinput autocomplete=\u0022off\u0022 data-drupal-selector=\u0022form-jaffvjjybeqv1n3n5uvdlrwt5uoinowkze-y97m4b-m\u0022 type=\u0022hidden\u0022 name=\u0022form_build_id\u0022 value=\u0022form-JafFvjJYBeQV1N3N5UvDlRwt5UoinowkzE_Y97m4b_M\u0022 \/\u003E\n\u003Cinput data-drupal-selector=\u0022edit-modal-form-example-modal-form\u0022 type=\u0022hidden\u0022 name=\u0022form_id\u0022 value=\u0022modal_form_example_modal_form\u0022 \/\u003E\n\u003C\/form\u003E\n\u003C\/div\u003E","dialogOptions":{"width":"800","modal":true,"title":"Republish this content"}}]