Thursday February 25, 2021 at 6:30pm, the Science-Actions association invites you to discuss astronomy and astrophysics. The Café science " Mystères dans le ciel " is offered as a videoconference(instructions for use).
[Watch the webconference replay].
Mysteries in the sky
Observing the sky (astronomy) and explaining the phenomena observed by physics (astrophysics) often confuses our common sense as human beings, because the orders of magnitude and physical laws involved are extraordinarily far removed from what we know in our daily lives as bipedal terrestrials. What's more, scientists can't explain, with today's physical theories at any rate, what are still enigmas, for example, to name but a few:
- What is dark energy?
- What is this invisible "missing" matter, dark matter?
- What happened to the visible matter of our everyday lives (whose elementary constituents are called baryons) that we should be seeing in greater quantities in the universe?
- Why is the Sun's surface so hot?
- Why isn't the surprising antimatter as widespread in the universe as the matter we know?
- Why is the solar system made up of so many different planets?
But knowledge is progressing, and attempts are being made to explain these enigmas. For example, using recordings of very brief bursts of radio waves (FRB, Fast Radio Burst) from space, it has been possible to extrapolate that the space between stars and galaxies contains minute quantities of matter (1 baryon per m3). Is this matter, which until now has eluded our observations due to its rarity, the dark matter we've been looking for? And do we have any idea what is emitting these phenomenally energetic FRBs? Very recently, the Gran Sasso underground observatory in Italy reported the recording of a signal corresponding to a hypothetical extremely light particle, the axion, which could explain part of the missing dark matter: extraordinary discovery or measurement artefact? Even closer to home, observation of the planets in our solar system reveals some extraordinary phenomena: for example, the small planet Ceres, orbiting Jupiter, has volcanoes of ice on its surface, leaking brine in the same way as the lava in terrestrial volcanoes.
Come and discuss this topic with speakers specializing in this field:
- Damir Buskulic, professor atUniversité Savoie Mont Blanc, gravitational waves, LAPP laboratory (CNRS/USMB), Annecy le Vieux, France
- Elisabeth Maris, president of the Céphée 73 astronomy club, Chambéry
- Gilles Maurin, lecturer atUniversité Savoie Mont Blanc, gamma-ray astronomy, LAPP laboratory (CNRS/USMB), Annecy le Vieux, France
- Pierre Salati, professor atUniversité Savoie Mont Blanc, physicist, astrophysics, LAPTH laboratory (CNRS/USMB), Annecy le Vieux
- Bernard Schmitt, CNRS Research Director, Planetology, Grenoble Institute of Planetology and Astrophysics
SCIENCE CAFÉS
The Cafés Science are an opportunity for the general public to discuss a wide range of topics, often of topical interest, with experts, researchers and professionals in a convivial atmosphere. They are organized by the Science-Actions association, in collaboration with :
- l'Université Savoie Mont Blanc
- the city of Chambéry
- Astrée cinema
- Chambéry MJC