Project description DEENESFRITPL Uncovering the nature of dark matter with stellar streams Dark matter has never been detected, yet gives itself away by its gravitational pull on stars and galaxies. Stellar streams, remnants of smaller galaxies that have been torn apart by the gravitational force of the Milky Way, are particularly susceptible to the effects of dark matter. The EU-funded project GREATDIGINTHESKY will develop analysis techniques to enable scientists to combine data from all relevant astronomical surveys with Gaia’s future data releases. The aim is to identify 100 galactic star streams throughout the project duration. These ground-breaking studies will help scientists test gravity and dark matter theories and probe dark matter substructure and distribution in our galaxy. Show the project objective Hide the project objective Objective Why most of the matter in the Universe appears to be dark, and constituted of some unknown particles, is one of the most important open questions in physics today. Here we propose to investigate the relative merits of different possibilities for the nature of this dark matter, as well as alternative proposals for the nature of the gravitational interaction, by comparing their predictions to new high spatial resolution measurements of the 3D acceleration field in the Milky Way. These measurements will be achieved primarily by finding and analysing the many stellar streams that criss-cross our Galaxy. We have already built a stream-finding prototype that we have used with the Gaia mission’s second data release (DR2) to detect 13 new beautiful phase-space streams in the Milky Way. This project aims to develop analysis techniques that will allow us to combine data from all relevant sky surveys together with future Gaia releases to identify many other Galactic star streams. It is plausible that 100 or more streams may be identified by the end of our project. The conjoint analysis of these interwoven structures will provide us with the means to derive, for the very first time, the three-dimensional acceleration field on scales of 1-100 kpc. The streams will be used to probe the granularity of the dark matter distribution, testing whether their kinematics and sub-structure are consistent with interaction with the expected sub-halos of the standard Λ Cold Dark Matter (ΛCDM) paradigm. We will also simulate star streams in several alternative scenarios, including fuzzy dark matter, dipolar dark matter, superfluid dark matter, and modified Newtonian dynamics, and quantify their relative merits to simulations in ΛCDM. Together, these studies will test theories of gravity and dark matter theories, place the best constraints on the distribution of dark matter in our Galaxy, and probe the substructure of the dark matter, thereby setting the state of the art for the next decade. Fields of science natural sciencesphysical sciencesastronomyastrophysicsdark matter Programme(s) H2020-EU.1.1. - EXCELLENT SCIENCE - European Research Council (ERC) Main Programme Topic(s) ERC-2018-ADG - ERC Advanced Grant Call for proposal ERC-2018-ADG See other projects for this call Funding Scheme ERC-ADG - Advanced Grant Coordinator CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS Net EU contribution € 2 370 250,50 Address Rue michel ange 3 75794 Paris France See on map Region Ile-de-France Ile-de-France Paris Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 0,00 Beneficiaries (2) Sort alphabetically Sort by Net EU contribution Expand all Collapse all CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS France Net EU contribution € 2 370 250,50 Address Rue michel ange 3 75794 Paris See on map Region Ile-de-France Ile-de-France Paris Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 0,00 Third-party Legal entity other than a subcontractor which is affiliated or legally linked to a participant. The entity carries out work under the conditions laid down in the Grant Agreement, supplies goods or provides services for the action, but did not sign the Grant Agreement. A third party abides by the rules applicable to its related participant under the Grant Agreement with regard to eligibility of costs and control of expenditure. UNIVERSITE DE STRASBOURG France Net EU contribution € 102 487,50 Address Rue blaise pascal 4 67081 Strasbourg See on map Region Grand Est Alsace Bas-Rhin Activity type Higher or Secondary Education Establishments Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 0,00