Contatto di riferimento: Cristian Vignali
Partecipanti: Gisella Clementini (INAF, Osservatorio Astronomico di Bologna)
Abstract
After a few months commissioning spent scanning the two ecliptic poles,Gaia, the European Space Agency cornerstone mission successfully launchedon 19 December 2013, entered into nominal mission in July 2014,and it has been regularly scanning the sky in every directionto a faint limit of G=20.7 mag since then.Gaia is expected to observe thousands of variable sources.Discovery of several thousands (~ 9,000) new Galactic Cepheids andmeasure of parallax for more than a thousand of them, along with thousandsof the Cepheids in the Magellanic Clouds, are expected from Gaia.Similarly, Gaia is expected to observe about 70,000 RR Lyrae stars in theGalactic halo and about 15,000-40,000 in the MW bulge (most of which willbe new discoveries) and to provide parallax measurements with a few$\mu$as uncertainty (standard error) for those brighter than V ~ 12mag.This will allow the absolute calibration via parallaxes of these "primary"standard candles and, in turn, a total re-assessment of the whole cosmicdistance ladder.Status and activities of the satellite since launch will be brieflypresented with emphasis on preliminary results obtained for RR Lyrae starsand Cepheids observed during the commissioning phase and in light of thefirst Gaia data release which is less than one year away.
See you on thursday in the seminars’ room, floor -1, via Ranzani 1, on time at 14h.
Next seminars:
- Thursday October 1st, at 17:00, Aula della Specola (Via Zamboni 33) Roberto Battiston (Università di Trento)
- Thursday October 8th, at 14:00 Elio Antonello (INAF, Osservatorio Astronomico di Brera)
- Thursday October 15th, at 14:00 Mara Salvato (MPE, Garching, DE)
The complete list of seminars is available at: http://davide2.bo.astro.it/?page_id=4531
The organizers of seminars: