NGC 7142
Cr 442, C 2144+655 | |
---|---|
Associations | |
Constellation | Cepheus |
NGC 7142 is an open cluster about 6,200 light-years away in the constellation Cepheus.
Due to the observational difficulties NGC 7142 presents, it has been an infrequent topic of research. Current known studies include only work being done at the University of Kansas.
Description
NGC 7142 is located near the reflection nebula NGC 7129, which is a first indication that the cluster may be obscured by an interstellar cloud. Many studies have demonstrated this to be true dating back to the earliest investigations of this cluster. A thorough study of the Cepheus region concluded "that no part of the field may be considered unobscured."[2]
Other astronomers have noted that the
Due to the uncertain amount of interstellar reddening, precise determination of age for this cluster has been especially difficult. Based on NGC 7142's
Although thought to be an old cluster, NGC 7142 contains a surprisingly high number of blue stars.[3] This runs contrary to the standard model of cluster evolution which predicts that old clusters should be devoid of such stars since bluer stars are more massive and thus evolve and die off faster, which should prevent them from still being present. Such stars are said to be blue stragglers.
The distance to this cluster has also been difficult to determine, again, owing to the absorption. Estimates for the distance modulus range from 12.5[4] to 14.5.[6]
Due to the similarities between NGC 7142 and
References
- ^ a b c "NGC 7142". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-02-04.
- doi:10.1086/144523.
- ^ Bibcode:1965SvA.....8..780S.
- ^ Bibcode:1970A&A.....9..209V.
- doi:10.1086/132850.)
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: CS1 maint: multiple names: authors list (link - ^ doi:10.1086/132850.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - Bibcode:1961LowOB...5..133J.
- Bibcode:1991IBVS.3657....1S.
External links
- NGC 7142 on