After a PhD thesis in Darmstadt (Germany) and stays in Lyon and at CEA Bruyères-le-Châtel, Micaela Oertel joined the Laboratoire Univers et Théories (LUTH) in Meudon in 2005. Her research interests in nuclear astrophysics concern neutron stars, binary neutron star mergers and core-collapse supernovae. These objects are not only at the origin of some of the most energetic events in the Universe...
THE LMD GENERAL CIRCULATION MODELS : TOOLS FOR A BETTER
UNDERSTANDING OF ATMOSPHERIC PLANETARY PHYSICS. **A. Bierjon 1 , A. Delavois 1 , T. Pierron 1 , D. Bardet 1 , J. Naar 1 , A. Boissinot 1 , F. Forget 1 , E. Millour 1 , A. Spiga 1 , F. Hourdin 1 , T.Dubos 1 .
1 Laboratoire de Météorologie Dynamique, UMR CNRS 8539, Institut Pierre-Simon Laplace,
Sorbonne Universités, UPMC Univ Paris...
Introduction: Corroborating evidences in geomorphology and modeling has unveiled the presence of a subsurface latitude-dependent mantle (LDM) of water-ice-rich deposits down to 30° latitude in both martian hemispheres [1]. These layers appear to be less than ~ 2Myr and were possibly deposited as snowfall in response to climate change driven by shift in obliquity, similar to Earth...
50 ans après les premiers pas de l’Homme de sur la Lune, continuons à faire rêver et sensibilisons l’auditoire aux enjeux de la recherche spatiale. Nous avons lancé STAR’sUP en 2019 convaincus qu’un festival exigeant, mais résolument grand public et créatif est un outil fédérateur. STAR’s UP est le festival où se rencontrent les spécialistes – tant publics que privés - des sciences de l’espace...
Galaxy evolution from a star-forming active galaxy rich in gas, dust, and young blue stars to a passive, ‘dead’ galaxy, void of gas and filled with an old population of red stars depends mainly on the molecular gas reservoirs present inside a galaxy. Molecular gas plays an important role since it acts as a star formation fuel. Detecting and estimating the molecular gas content inside a galaxy...
The Schmidt-Kennicutt law links the star formation rate (SFR) of a galaxy or its subregions to the contained amount of gas, and remains true for a wide range of galaxies and redshifts. Understanding its origin is crucial to improve our knowledge of the star formation process. One main question is to determine which are the processes responsible of the regulation of the star formation rate,...
Cepheids represent a fundamental tool for measuring the distances in the Universe thanks to the Leavitt law (period-luminosity) relation. In order to calibrate this relation accurately, precise distance measurements are required. The Gaia satellite monitors a large number of Galactic Cepheids, and will eventually provide extremely accurate parallaxes to hundreds of them. This will considerably...
Using GeMS-Gemini high angular AO-aided imaging in the near-IR, together with a radiative transfer code, we study the population of Super Stellar Clusters (SSCs) in terms of age, extinction, mass and luminosity. We detect with a fair degree of confidence 54 SSCs of mKs between 15 mag and 22 mag with a median photometric accuracy of 0.14 mag. When plotted on a color-color diagram and a...
The X-ray light-curves of gamma-ray burst afterglows commonly feature phases of shallowly decaying or constant flux lasting from hundreds of seconds to a day, known as plateaus. Correlations exist between observable properties of the plateau and of the prompt emission for bursts with plateaus. Over the years, the origin of these plateaus has been tentatively traced to various mechanisms. These...
Far more than an association serving solely its own members, the Association Française d'Astronomie (AFA), recognised as promoting the public interest, acts to enable and motivate the public to take an interest in the sciences of the Universe. By discovering and sharing knowledge, it aims to help citizens play an active role in their education. Through astronomy, it tries...
Since the first exoplanet detection in 1995, more than 4000 planets have been discovered. In the past tweny five years, the observations tools have greatly improved, increasing the statistics and revealing the diversity of planets. With the upcoming space telescopes such as James Webb and Ariel, detailed knowledge of exoplanet atmospheres will become possible. This opens up new challenges in...
Q U Bolometric Interferometer for Cosmology (QUBIC) is a new ground-based experiment aiming to detect the Cosmic Microwave Background (CMB) B modes. QUBIC is based on bolometric interferometry, a new instrument architecture. This combines together the well known control of systematic effects from interferometers with the high sensitivity of bolometric detectors. It will observe the...
Ultra-long Gamma-Ray Bursts (ulGRBs) are Gamma-Ray Bursts (GRBs) with an unusually long emission in X and gamma rays, reaching durations of thousands of seconds. They could form a specific class of high-energy transient events, whose origin is still under discussion. The current sample of known ulGRBs consists of a few 10s of events which have been detected so far by the Burst Alert Telescope...
Despite plenty of evidence for the existence of Dark Matter (DM), no experiment has ever managed to capture it directly. In the last decades, the Weakly Interacting Massive Particle (WIMP) paradigm, the most popular among the DM models, has proven unsuccessful experimentally in a variety of detection methods in the GeV-TeV mass range. DAMIC-M (DArk Matter In CCDs at Modane) will aim to...
Among the unexpected features revealed by MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER) mission on the surface of Mercury, geological units named hollows are the most surprising and least understood. Possibly related to volatile components, hollows are small depressions, surrounded by bright halo, never observed on other body in our Solar System. The multispectral...
Anthony Challinor
Institute of Astronomy, University of Cambridge, Cambridge, Royaume-Uni
« Backlighting the dark universe with the cosmic microwave background »
Invited by : BOUCHET François and CODIS Sandrine
http://www.iap.fr/vie_scientifique/seminaires/resumes.php?nom_seminaire=Seminaire_IAP&numero=3521
Gravitational waves from binary neutron star (BNS) coalescence, in association to short gamma-ray burst, opened a new era of multi-messenger astronomy. The identification of the counterpart and its multi-wavelength observations improved our understanding of the physics of strong-field gravity and put some constraints on astrophysical models related to matter during the merger and post-merger...
Jets and outflows are observed in a diverse range of accreting systems such as young stellar objects, galactic X-ray binaries and active galatic nuclei. The formation of jets, their propagation and their association with accretion processes are still largely unclear. However, their feedback on their immediate environment is now starting to be quantified, as their interaction with the...
FIRST (Fibered Imager foR a Single Telescope) is an original instrument dedicated to imaging substellar companions at high contrast and high angular resolution in the visible. Its principle is based on the pupile remapping technique, which turns a monolithic telescope into an interferometer. Thanks to the monomode filtering operated by the optical fibers and an appropriate beam recombination...
SpaceBus France est une association Loi 1901 à but non lucratif créée en 2017 et gérée bénévolement par des docteur.e.s en astronomie. Les objectifs de notre association sont de :
- faire découvrir l'astronomie et la science de manière ludique au grand public grâce à des animations ludiques et interactives,
- former à la démarche scientifique et créer des vocations,
- créer un lien...
Water ice clouds have been observed in the Martian atmosphere since 1972, but as recent studies have shown their important role in the martian climate there is a growing need to better characterize the properties of water ice aerosols with observational constraints.
The Atmospheric Chemistry Suite (ACS) instrument onboard the ExoMars Trace Gas Orbiter (TGO) ESA-Roscosmos mission began...
