Notte Europea dei Ricercatori 2023
In occasione della Notte Europea dei Ricercatori 2022, l’INAF-Osservatorio Astrofisico di Catania ha organizzato varie attività per il pubblico che si svolgeranno tra il 28 e il 30 settembre.
10 eventi trovato.
eventi-seminari
Studying the rotation of solar-type stars, from the surface to the core
Being able to constrain the rotation profile, both radial and latitudinal, of main-sequence solar-type stars, from the surface to the core, is a fundamental problem if we want to improve our understanding of stellar evolution (especially in order to get better constraints on stellar ages) and of the interactions of stars with their environment. As of today, the core rotation profile of the Sun and other main-sequence solar-type stars remains a mystery.
Cleaning RV time series from stellar activity: SN-fit and bp-method
The radial velocity (RV) technique is one of the most successful method for detecting exoplanets and it is based on measuring the Doppler reflex motion induced on a star by its orbiting planets. However, the stellar activity in the form of oscillations, granulations, spots or faculae also produces Doppler signals which may completely hide the Keplerian signal of an exoplanet.
Unveiling the atmospheric evolution of exoplanets: the PASTA tool
A thorough characterisation of an exoplanetary system includes also studying the evolution of planetary atmospheres. To this end, we developed a custom Python tool that we have dubbed PASTA: Planetary Atmospheres and Stellar roTation rAtes. The tool runs within a Bayesian framework and it adopts a MCMC scheme to estimate the atmospheric content of exoplanets at the dispersal of the protoplanetary disk accounting for the present day system observables. As a positive by-product, the evolution of the stellar rotation period is reconstructed as well. In detail, our tool relies on planetary evolutionary models relating mass, radius and equilibrium temperature with the expected atmospheric mass fraction and mass loss rate, the latter derived from hydrodynamic simulations. The atmospheric mass loss rate is significantly influenced by the stellar activity level, which is estimated from the stellar rotation period via empirical relations. In particular, gyrochronology and theoretical stellar evolutionary tracks are essential to evaluate the high-energy emission over time. We have successfully applied this framework to a number of recently discovered planets, including various CHEOPS targets. The synergy between CHEOPS and radial velocity spectrographs have already allowed us to identify different systems amenable to PASTA’s analysis, so to constrain the planet formation and stellar evolution.
Michelson-Morley Experiments: An Enigma for Physics and the History of Science
The “null result” of the original 1887 Michelson-Morley experiment represents a fundamental step for physics and the history of science. Since then, more and more precise measurements have apparently strengthened the original interpretation. However, in principle, if the two-way velocity of light in the interferometers is not exactly the same parameter “c” of Lorentz transformations, nothing would prevent a non-zero effect. For instance, in a gaseous medium the small fraction of refracted light could keep track of the motion of matter with respect to some preferred reference frame. Starting from this observation, there is now a new interpretation where the small irregular residuals always observed in laboratory show intriguing correlations with the direct CMB observations with satellites in space. This opens the possibility of linking the CMB to a fundamental reference system for relativity with substantial implications for cosmology and the interpretation of non-locality in the quantum theory. The talk will focus on the basics of this research with brief notes on some leading scientists involved in these measurements.
The Evolutionary Map of the Universe
EMU, the Evolutionary Map of the Universe, is an ongoing ASKAP survey of the Southern three-quarters of the sky, aiming to achieve rms noise levels of 20 μJy. EMU will support a broad range of science, spanning star formation and evolution in our own Galaxy, galaxy evolution and the links between star formation and supermassive black holes, to cosmology. EMU has been allocated approximately 1 year of time on ASKAP in the coming 5 year window. I will summarise the technical and scientific goals of the survey, the current status of and timeline for the survey, and highlight a selection of recent results from early science and pilot survey data.
Avvistamento lunare
Un incontro dedicato all’avvistamento, assistito con strumentazione astronomica, della Luna Nuova di Ramadan.
Comunicazione@INAF
Sede A. Riccò Via Santa Sofia 78, CataniaLa terza missione sta diventando sempre più cruciale per enti di ricerca e atenei, in particolare tutte quelle attività che vanno sotto il nome di Public Engagement o, se preferite, Comunicazione nel senso più ampio del termine. Attività che vedono coinvolti sempre più ricercatori e ricercatrici in prima persona. In questo incontro vorremmo fornirvi alcuni strumenti per orientarvi al meglio e per collaborare secondo le attitudini e le aspirazioni di ciascuno di voi, ma anche dirvi com’è articolata la Struttura per la comunicazione dell'INAF. Ma, soprattutto, vorremmo dare risposta alle tante domande che spesso ci ponete: cosa si intende per press release, news, conferenza stampa, embargo, comunicato congiunto, virgolettato e cose simili? A chi vi rivolgete? Cosa posso raccontare a bambini e bambine di sei anni? Perché a volte avete così fretta di contattarmi mentre sono impegnato in un meeting o una call? Perché non mi hanno accettato al festival della scienza? E, soprattutto, perché parlate di qualunque cosa tranne che delle mie ricerche?
Segnalati
Nati sotto il segno di Dike, cresciuti con quello della Bilancia – La storia della Space Law, tra gravità e giurisprudenza
Sede A. Riccò Via Santa Sofia 78, CataniaIn questo seminario pongo l'attenzione su quei particolari momenti in cui la scienza giuridica ha felicemente intersecato l’osservazione pre-scientifica della natura e, in seguito, le scienze fisiche propriamente dette, traendo da esse, specie nel passato, quando ispirazione, quando una maggiore forza argomentativa.
Si tratta di incroci che sembrano denunciare in modo chiaro un’origine comune dello sguardo del fisico e del giurista - un’origine di sicuro meritevole di uno studio storico e filosofico più attento che già sto conducendo – e che la presente ricerca evidenzia solo per la parte avente a che fare con la descrizione di come la nostra specie si è progressivamente impossessata dello spazio esplorabile: un concetto usato in una fase iniziale esclusivamente per indicare territori sulla terraferma e che, al progressivo crescere delle acquisizioni scientifiche, tecnologiche e di una parallela evoluzione giuridica, ha subito diverse modifiche che gli hanno fatto guadagnare pure il significato di distese marine, di spazi aerei al di sopra delle nazioni e, in tempi più recenti, quello di spazio esterno alla nostra atmosfera. Uno spazio oramai teatro di dispute di diritto internazionale e scenario di possibili scontri bellici del futuro.
Diagnostics of the solar corona expansion through Metis coronagraph observations
Sede A. Riccò Via Santa Sofia 78, CataniaThe solar corona has been investigated in the last decades through observations coming from several spacecraft. The Metis coronagraph, aboard the ongoing Solar Orbiter mission, extends the UVCS/SOHO spectrocoronagraph observations of the scattered ultraviolet emission of the coronal plasma performed during solar activity cycle 23, by simultaneously imaging the coronal visible light polarised brightness (VL pB), in the spectral bandpass 580-640 nm, and the coronal ultraviolet H I Lyα emission, in the spectral window 121.6 ± 10 nm. Here some specific observations are shown, such as those taken on May 15, 2020, from which important results about the solar wind outflow velocity were inferred by applying the Doppler dimming technique. Other results on the coronal solar wind velocity are presented, obtained by considering the data acquired during the first quadrature of the Solar Orbiter and the Parker Solar Probe (PSP) spacecraft with respect to the Sun. In particular, the same parcel of plasma on the East limb was remotely observed with Metis between 3.5 R⊙ and 6.3 R⊙ on January 17, 2021, during low-cadence synoptic mode observations, and was sampled in situ by PSP at about 22 R⊙ on January 18, 2021. In this case, information about several coronal parameters were inferred with unprecedented details, thanks to the high quality of Metis and PSP data. Finally, other results concerning the first coronal mass ejection observed with Metis on January 16-17, 2021 are reported. In this case, also considering data coming from instruments onboard Solar Orbiter and other spacecraft, a 3D reconstruction and detailed physical information about this structure were obtained. Therefore, Metis, even when operates in synoptic mode and in synergistic coupling with other instruments, allows to get novel and detailed information about the structure of the solar corona with an accuracy never reached until now.