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Date and Time of the Query: 2019-04-20 T13:28:37 PDT
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Notes for object NGC 2885

2 note(s) found in NED.


1. 1998A&A...332..449D
Re:NGC 2885
3.3. NGC 2885
NGC 2885 (Fig. 3) exhibits strong unresolved X-ray emission. A second source,
which was serendipitously detected ca. 13" south of it, has no visible optical
counterpart. Note that this is an image summed up from two observations.
NGC 2885, without the confusing second source, is visible in Fig. 7. Both
NGC 2885 and the southern source are highly variable in the X-ray regime.
Strong X-ray variability on timescales of months was detected in NGC 2885 =
RX J0927.3+2301 (Bade et al. 1995). The change in flux of the central source
from the first observation to the second is a factor of 2.15. The variability
of the bright unresolved central X-ray source indicates the existence of a
Seyfert nucleus. Thus, we determined the X-ray flux, f_x_, under the assumption
of an {alpha}=1 power law emission spectrum (attenuated only by Galactic
foreground gas). {alpha}=1 is close to the value determined by Bade et al.
(1995) of {alpha}=0.88+/-0.19.
Both our observations show a source (or sources) that are considerably brighter
than during the ROSAT All-sky Survey (RASS; Bade et al. 1995). At that time (the
second half of 1990), the PSPC count rate of RX J09237+2301 was 0.2
cts s^-1^. Comparing the PSPC energy conversion factor (ECF) listed by
Briel et al. (1994), of 0.55 10^11^ cts cm^2^ erg^-1^, with that for the HRI,
the PSPC count rate corresponds to an expected HRI count rate of 0.034
cts s^-1^. On 1994, Nov. 18 we measured 0.24 cts s^-1^ with the HRI.
Considering that the PSPC cannot resolve the two sources, we can also compare
the expected HRI count rate at the time of the RASS with the combined HRI count
rate of RX J09237+2300 and NGC 2885 in the 1995 Apr. 25 data of 0.353
cts s^-1^. This means that the variability from the RASS to our observations
exceeds factors of 7 and 10, respectively. The luminosity of NGC 2885 lies
around 10^43^ erg s^-1^, which is ca. 15-45 times higher than those of the
central parts of the E/S0 galaxies listed in Table 2. Note that even this
value of L_x_ is a lower limit because of the assumption of the absence of
intrinsic X-ray absorption. Optical imaging (DSS, see Fig. 3, and a B -band
image by N. Bade) suggests that NGC 2885 is an early-type spiral galaxy,
possibly of type Sa. The observed X-ray luminosity and variability confirm the
identification of NGC 2885 as a Seyfert galaxy from optical spectroscopy
(Bade et al. 1995). The galaxy's classification (NED; RC3) as an S0 galaxy is
doubtful, however.

2. 1973UGC...C...0000N
Re:UGC 05037
Brightest in group of 6
09 24.2 +23 12 at 3.2, 230, 0.45 x 0.25, m=15.5
09 24.5 +23 15 at 1.8, 69, 0.4 x 0.4, m=15.6, this is {not} IC 538
(UGC 05037 is identified as IC 538 in MCG {MCG is correct. H. Corwin})


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