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par une source d’arri&amp;#232;re-plan (&amp;#233;toile ou galaxie) et re&amp;#231;ue sur Terre. En l’absence de d&amp;#233;viation,
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(microlensing) pour calculer la masse d’une lentille pr&amp;#233;sente dans notre Galaxie.</langstring><langstring xml:lang=""/></description><keyword><langstring xml:lang="fr">demonstrator</langstring><langstring xml:lang="fr"> cosmologie</langstring><langstring xml:lang="fr"> relativite generale</langstring><langstring xml:lang="fr"> lentille gravitationnelle</langstring><langstring xml:lang="fr"> galaxies</langstring><langstring xml:lang="fr"> etoiles</langstring><langstring xml:lang="fr"> magnitude</langstring></keyword></general><lifecycle><status><source>LOM v1.0</source><value>final</value></status><version><langstring xml:lang="en">1.0</langstring></version><contribute><role><source>LOM v1.0</source><value>author</value></role><date><datetime>2012-09-27</datetime><description/></date><centity><vcard/></centity></contribute><contribute><role><source>LOM v1.0</source><value>publisher</value></role><date><datetime>2012-09-27</datetime><description/></date><centity><vcard/></centity></contribute></lifecycle><metametadata><language>fr</language><metadatascheme>LOM v1.0</metadatascheme><contribute><role><source>LOM v1.0</source><value>creator</value></role><date><datetime>2012-09-27</datetime><description/></date><centity><vcard/></centity></contribute><contribute><role><source>LOM v1.0</source><value>validator</value></role><date><datetime/><description/></date><centity><vcard/></centity></contribute></metametadata><technical><duration><datetime/><description/></duration><requirement><type><source>LOM v1.0</source><value>browser</value></type><name><source>LOM v1.0</source><value>any</value></name><minimumversion/><maximumversion/></requirement><requirement><type><source>LOM v1.0</source><value>os</value></type><name><source>LOM v1.0</source><value>any</value></name><minimumversion/><maximumversion/></requirement><installationremarks/><otherplatformrequirements/><size></size><format>text/html</format><location>http://portal.discoverthecosmos.eu/node/187677</location></technical><rights><cost><source>LOM v1.0</source><value>no</value></cost><copyrightandotherrestrictions><source>LOM v1.0</source><value>no</value></copyrightandotherrestrictions><description/></rights><educational><interactivitytype><source>LOM v1.0</source><value>active</value></interactivitytype><interactivitylevel><source>LOM v1.0</source><value>high</value></interactivitylevel><semanticdensity><source/><value/></semanticdensity><difficulty><source>LOM v1.0</source><value>medium</value></difficulty><learningresourcetype><source>LOM v1.0</source><value>exercise</value></learningresourcetype><learningresourcetype><source>LOM v1.0</source><value>video</value></learningresourcetype><learningresourcetype><source>LOM v1.0</source><value>narrative text</value></learningresourcetype><learningresourcetype><source>LOM v1.0</source><value>Inquiry-Based Teaching</value></learningresourcetype><context><source>LOM v1.0</source><value>2 didactic hours</value></context><typicalagerange><langstring xml:lang="en">12-15</langstring><langstring xml:lang="en">15-18</langstring><langstring xml:lang="en">18-25</langstring></typicalagerange></educational><classification><purpose><source>LOM v1.0</source><value>Discipline</value></purpose><taxonpath><source><langstring xml:lang="en">Science</langstring></source><taxon><id/><entry><langstring xml:lang="en">Astronomy: Cosmology</langstring><langstring xml:lang="en">Astronomy: Einstein ring</langstring><langstring xml:lang="en">Astronomy: Galaxies</langstring><langstring xml:lang="en">Astronomy: Gravitational lenses</langstring><langstring xml:lang="en">Astronomy: Quasars</langstring><langstring xml:lang="en">Astronomy: Stars</langstring><langstring xml:lang="en">Astronomy: Theory of relativity</langstring></entry></taxon></taxonpath><description/></classification></lom>
