A&A 445, 493-501 (2006)
DOI: 10.1051/0004-6361:20053254
Open clusters in the Third Galactic Quadrant
II. The intermediate age open clusters NGC 2425 and NGC 2635
A. Moitinho1, G. Carraro2, 3, 4, G. Baume5 and R. A. Vázquez51 CAAUL, Observatório Astronómico de Lisboa, Tapada da Ajuda, 1349-018 Lisboa, Portugal
e-mail: andre@oal.ul.pt
2 Departamento de Astronómia, Universidad de Chile, Casilla 36-D, Santiago, Chile
3 Yale University, Department of Astronomy, PO Box 208101, New Haven, CT 06520-8101, USA
4 Dipartimento di Astronomia, Università di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy
5 Facultad de Ciencias Astronómicas y Geofísicas de la UNLP, IALP-CONICET, Paseo del Bosque s/n, La Plata, Argentina
(Received 16 April 2005 / Accepted 29 July 2005 )
Abstract
We analyse CCD broad band (
) photometric
data obtained in the fields of the poorly studied open clusters
NGC 2425
and
NGC 2635
. Both clusters are found
to be of intermediate age thus increasing the population of open
clusters known to be of the age of, or older than, the Hyades.
More explicitly, we find that
NGC 2425
is a 2.2 Gyr old
cluster, probably of solar metallicity, located at 3.5 kpc from
the Sun.
NGC 2635
is a Hyades age (600 Myr) cluster
located at a distance of 4.0 kpc from the Sun. Its Colour
Magnitude Diagram reveals that it is extremely metal poor for its
age and position, thus making it a very interesting object in the
context of Galactic Disk chemical evolution models.
Key words: Galaxy: open clusters and associations: individual: NGC 2425 , NGC 2635
SIMBAD Objects
Tables at the CDS
© ESO 2005

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