Lengths of cluster-type periods in Messier 22 and other globular clusters.
نویسندگان
چکیده
منابع مشابه
The Lower Main Sequence and Mass Function of the Globular Cluster Messier 4
The deepest optical image ever in a globular star cluster, a Hubble Space Telescope (HST) 123 orbit exposure (GO 8679, cycle 9) in a single field of Messier 4, was obtained in 2 filters (F606W – V, F814W – I) over a 10 week period in early 2001. A somewhat shallower image obtained in 1995 (GO 5461, cycle 4) allowed Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the ...
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ژورنال
عنوان ژورنال: The Astronomical Journal
سال: 1944
ISSN: 0004-6256
DOI: 10.1086/105812