Star Formation Histories, Abundances and Kinematics of Dwarf Galaxies in the Local Group

85 Pages·2014·28.01 MB·English

Star Formation Histories, Abundances  
and Kinematics of Dwarf Galaxies in the
Local Group
Eline Tolstoy, Kapteyn Astronomical Institute, University of Groningen
Science With The Hubble Space Telescope IV, Rome, March 2014
star by star
Milky Way from Paranal credit: ESO/Yuri Beletsky
star by star
Galileo Galilei
"... congeries stellularum...."
Sidereus Nuncius, 1610
Milky Way from Paranal credit: ESO/Yuri Beletsky
What can we Learn?
We have the most ancient objects in the Universe sitting
relatively nearby in the Milky Way and in the Local Group.
What can we Learn?
We have the most ancient objects in the Universe sitting
relatively nearby in the Milky Way and in the Local Group.
We understand stellar evolution well enough to make stars reliable
clocks to track back the evolutionary history of star formation & in
dwarf galaxies we see the whole picture more easily.
What can we Learn?
We have the most ancient objects in the Universe sitting
relatively nearby in the Milky Way and in the Local Group.
OLD (FAINT) STARS
We understand stellar evolution well enough to make stars reliable
clocks to track back the evolutionary history of star formation & in
dwarf galaxies we see the whole picture more easily.
What can we Learn?
We have the most ancient objects in the Universe sitting
relatively nearby in the Milky Way and in the Local Group.
OLD (FAINT) STARS
We understand stellar evolution well enough to make stars reliable
clocks to track back the evolutionary history of star formation & in
dwarf galaxies we see the whole picture more easily.
SMALL GALAXIES - NEARLY COMPLETE COVERAGE
Colour-Magnitude Diagram Analysis
e
d
u
t
in
g
a
m
colour
Tosi et al. 1991; Aparicio et al. 1996; Tolstoy & Saha 1996; Dolphin 1997, 2002; Hernandez et al. 2000;
Ikuta & Arimoto 2002; Gallart et al. 2005; Cignoni & Tosi 2010; de Boer et al. 2012
Colour-Magnitude Diagram Analysis
e
d
u
t
in
g
a
m
colour
Tosi et al. 1991; Aparicio et al. 1996; Tolstoy & Saha 1996; Dolphin 1997, 2002; Hernandez et al. 2000;
Ikuta & Arimoto 2002; Gallart et al. 2005; Cignoni & Tosi 2010; de Boer et al. 2012
Colour-Magnitude Diagram Analysis
e
d
u
t
in
g
a
m
colour
Tosi et al. 1991; Aparicio et al. 1996; Tolstoy & Saha 1996; Dolphin 1997, 2002; Hernandez et al. 2000;
Ikuta & Arimoto 2002; Gallart et al. 2005; Cignoni & Tosi 2010; de Boer et al. 2012