NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-23 T03:23:08 PDT
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Notes for object MESSIER 030

2 note(s) found in NED.


1. 2001A&A...368..137V
Re:NGC 7099
3.55 NGC 7099/M 30
This cluster is the target of two PSPC observations, and in the field of
view of a much longer observation of the galaxy cluster MS 2137.3-2353. A
source in the globular cluster is detected in all three observations, at
countrates consistent with a constant value. The numbers given in Table 2
are from the combined image of the shorter observations directed at the
cluster. One new source, X13 not related to the cluster, is detected with
respect to the analysis by Johnston et al. (1994). The cluster source has
a countrate in channels 11-240 of 11.0 +/- 1.8 cts ksec^-1^, higher than
in the hard channels only (Table 2); this indicates a soft spectrum. With
N_H_ = 1.6 x 10^20^ cm^-2^, as estimated from the visual reddening of the
cluster, a bremsstrahlung spectrum of kT >~ 0.8 keV gives the observed
ratio of countrates.

2. 1918PLicO..13....9C
Re:NGC 7099
M. 30. Bright globular cluster 5' in diameter. 25 s.n.


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