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Notes for object MESSIER 032

18 note(s) found in NED.

1. 2009MNRAS.397.2148G
Ferrarese et al. (2006a) suggest that M32 may contain both a nuclear star
cluster (Smith 1935; Burbidge 1970; Worthey 2004) and a BH (Verolme et al. 2002,
M_BH_= 2.5^+0.5^_-0.5_* 10^6^ M_{sun}_). In Fig. A3, we present an I-band light
profile which we have fitted with an inner nuclear component, plus a Sersic
bulge and an outer exponential envelope/disc (see Graham 2002). The inner
component and the main spheroid component have an apparent F814W magnitude of
10.0 and 7.5 mag, respectively. The Sersic index n of the inner component is 2.3
(the effective half-light radius is 1.65 arcsec, equal to ~6 pc). Together with
the Milky Way's nuclear star cluster, this paper presents the first clear
evidence/statement that nuclear excesses do not all have a Gaussian-like
structure (i.e. n= 0.5).
Although we initially excluded M32 due to the somewhat unknown nature of its
central excess, spectroscopy has revealed that the inner region of M32 does
possess a different mean chemistry and age (e.g. Worthey 2004; Rose et al. 2005)
to the main spheroid, although no obvious transitional radius is apparent. This
difference has most recently been quantified by Coelho, Mendes de Oliveira & Cid
Fernandes (2009), using an inner 1.5 arcsec slit to sample the nuclear region.
Using the spread of ages and metallicties from their table 3 gives an I-band,
stellar M/L ratio of 0.75 +/- 0.17 and 0.92 +/- 0.18 for the nucleus and
main spheroid of M32.
Exclusion of M32 from the analysis has no significant effect on any of the

2. 2009ApJ...703.1034Y
M 32. The X-ray spectrum is well fitted by a jet. The dot-dashed line shows our
best fit by an ADAF; the fit is only marginally acceptable. However, the
required accretion rate at the Bondi radius is ~8 * 10^-6^M_sun_ yr^-1^, which
is about 10 times larger than the Bondi rate M_Bondi_ ~ (3-10) x 10^-7 M_sun_
yr^-1^ estimated by Ho et al. (2003) from Chandra observations. This situation
is very similar to the cases of M 31 and the quiescent state of the black hole
X-ray binary XTE J1118+480 (YC05). In the case of M 31, Garcia et al. (2005)
estimated the Bondi accretion rate from Chandra observations to be M_Bondi_ ~ 6
x 10^-6 M_Edd_. However, the X-ray luminosity produced by an ADAF with such an
accretion rate would be four orders of magnitude lower than the observed L_X_.
For XTE J1118+480, from optical observations together with disk instability
theory for the outburst, the mass accretion rate is estimated to be M ~
10^-6^M_Edd_ (McClintock et al. 2003). Again, an ADAF with such an accretion
rate would underpredict the X-ray luminosity by nearly four orders of magnitude
(YC05). If the X-ray radiation is dominated by a jet, on the other hand, this
will not be a problem at all. Taking M 32 as an example, the mass accretion rate
at the innermost region of the ADAF, say at 5 R_S_, is about
M_Bondi_(5R_S_/R_Bondi_)^0.3^ ~ 6 x 10^-7M_Edd_. So we only require 10^-8^/6 *
10^-7^ ~ 2% of the accretion matter transferred into the jet to produce the
correct X-ray flux. The physical reason is that the radiative efficiency of the
jet is much higher than that of an ADAF.

3. 2008MNRAS.386.2242H
Re:NGC 0221
NGC 221 (M32) - It is a small, low-luminosity elliptical, has a main
body of Sersic profile with index n < 4 and extra light near the
centre above the inward extrapolation of the outer Sersic function
(Kormendy 1999).

4. 2008MNRAS.386.2242H
Re:NGC 0221
NGC 221 (M32) - It is a small, low-luminosity elliptical, has a main body of
Sersic profile with index n < 4 and extra light near the centre above the inward
extrapolation of the outer Sersic function (Kormendy 1999).

5. 2007MNRAS.382.1552L
Re:NGC 0221
NGC 221 - M 32: Spectral synthesis by Bica et al. (1990) shows that the nuclear
spectra are dominated by an old (>10 Gyr) stellar population with solar
metallicities, although an intermediate-age population (~5 Gyr) is also
significant. These values agree very well with our results.

6. 2002ApJ...574..740T
The velocity dispersion is obtained from van der Marel et al. (1994),
and the black hole mass, M_BH_ = (2.5 +/- 0.5) x 10^6^ M_sun_, is from
Verolme et al. (2002). In estimating the dispersion, we have excluded
the region near the center that is strongly perturbed by the black
hole (see Fig. 6). Other recent mass estimates, by van der Marel
et al. (1998) and Joseph et al. (2001), give similar results:
(3.9 +/- 0.8) x 10^6^ and (3 +/- 1) x 10^6^ M_sun_, respectively.

7. 2001MNRAS.322..702M
M32 Our models use the minor-axis velocity dispersion profile obtained by
van der Marel et al. (1994) and the 15 PNe radial velocities measured by
Nolthenius & Ford (1986). These data are insufficient to place any
interesting constraints on whether M32 has a halo or not: the v_c_(r) and
{UPSILON}(r) profiles of our models are both consistent with being flat.
The results plotted are for models where we have subtracted a heliocentric
systemic velocity of -203 km s^-1^ (Tully 1988) from the PNe velocities.
Assuming systemic velocities of -195 km s^-1^ or -185 km s^-1^
(Nolthenius & Ford 1986) yields almost identical results.

8. 2001ApJS..132..129M
Re:NGC 0221
NGC 221 (M32). - A satellite to M31, M32 is a compact dwarf elliptical
galaxy noted for its high optical surface brightness. The UV images show a
compact, centrally concentrated source projected onto the disk of M31.
Enlarged UV images of M32 are shown in Figure 4a, while the full-field
versions from which these were extracted are shown in the NGC 224/M31
mosaics in Figures 5a-5b. M32 is the bright object near the left hand
(eastern) edge of the M31 UIT 25 mosaic, just below the overlap region.
OB stars in the M31 disk adjacent to M32 produce a complex background
which has been modeled and removed from our photometry, but which produces
greater uncertainty in the integrated UV magnitudes. M32 exhibits a good
fit to a de Vaucouleurs r^0.25^ profile for r <~ 40" in both the FUV and
MUV bands. Axial ratios of the UV isophotes match those of the optical
bands; this is true in general for the normal ellipticals in our sample.
M32 has the reddest central (FUV-MUV) color (after extinction corrections)
of any of the five normal early-type systems (M32, NGC 1399, NGC 1404, and
the bulges of M31 and M81) included in our sample. This is consistent with
results from IUE (Burstein et al. 1988; O'Connell et al. 1992). The R-band
photometry plotted in Figure 4b was interpolated from the major axis
profile data taken from Kent (1987). The sharp central rise in the R-band
flux with respect to the UV flux is partially an artifact of mismatched
spatial resolution.
There are strong radial gradients in both the (FUV-MUV) and (FUV-B)
colors. The colors become bluer with
increasing radius, contrary to the UV color gradients observed in other
dynamically hot systems (O'Connell et al. 1992; Ohl et al. 1998). As in the
case of M31 (below), individual massive stars hotter than B1 V would be
detectable in our UV images if they were present. No isolated point sources
are visible within M31 in the UV imagery. Instead, the UV light
distribution shows an azimuthally smooth, radial decline. This UV
morphology is typical of other normal E galaxies and spiral bulges and is
evidence that the far-UV light originates in low-mass stars (reviewed in
O'Connell 1999). HST UV imagery of the central region of M32 has been
presented by Bertola et al. (1995); Cole et al. (1998); and Brown et al.
(1998) with the FOC and WFPC2 cameras, and more recently by Brown et al.
(2000) with STIS. These images confirm the absence of luminous, massive OB
stars. The STIS images of Brown et al. (2000) are sufficiently deep to
resolve the horizontal branch (HB) and to confirm that the UV light in M32
is produced by a mixture of evolved hot HB stars and more luminous, but
shorter-lived, post-HB stars. The absence of a UV-bright nucleus is notable
since M32 is the densest resolvable extragalactic system (Lauer et al.
1998). Evidently, high stellar density alone is not sufficient to produce
an active nucleus or a nuclear population of UV-bright stars.

9. 2001AJ....122..653R
Re:NGC 0221
NGC 221 (M32): The significantly positive B_4_ values within r ~ 5"
suggest that a disky component is present in M32, although the residual
image does not show clear evidence for it. As in the optical
(Lauer et al. 1998), the galaxy is remarkably smooth and featureless in
the NIR.

10. 2000MNRAS.319...17L
Re:NGC 0221
NGC 221 (M 32): A strong off-nuclear source in NGC 221 has been found with
the HRI on both Einstein and ROSAT. The flux reported here is consistent
with the Einstein measurements F_X_ = 9.1 x 10^-13^ erg s^-1^ cm^-2^ in
the 0.5-4.0 keV bandpass (Fabbiano et al. 1992)]. The X-ray source lies
~7 arcsec away from the NGC 221 nucleus and has no optical counterpart.
ASCA observations of this source, reported by (Loewenstein et al. 1998)
reveal a hard spectrum and a flux decrease of 25 per cent in two weeks,
favouring the identification of the source as a single X-ray binary (XRB).
Variability by a factor of 3 has also been detected during ROSAT PSPC
observations (Supper et al. 1997). An upper limit for the nuclear X-ray
emission is given in Table 5. The position of the aperture used to compute
the upper limit was shifted slightly from the exact position of the
galactic nucleus to avoid contamination from the off-nuclear source.
Dynamical studies of the stellar rotation velocities in this galaxy have
revealed the presence of a central dark massive object, probably a black
hole, with mass 3 x 10^6^ M_sun_ (Bender, Kormendy & Dehnen 1996;
Van Der Marel, De Zeeuw & Rix 1997), which corresponds to an Eddington
luminosity of ~10^44^ erg s^-1^. The X-ray upper limit in Table 5 shows
that the central object is emitting at most 10^-8^L_Edd_.

11. 1999ApJ...519...89C
Re:NGC 0221
NGC 221 (M32).-M32 is the other normal dwarf elliptical
galaxy that is a companion to M31. Eskridge, White, & Davis (1996)
analyzed the ROSAT PSPC data for M32 and concluded that the emission
from the central source could be due to either low-mass X-ray binaries
or accretion onto a massive central black hole. Loewenstein et al.
(1998) argue that the central source is most likely a single X-ray
binary rather than an AGN, based on the presence of an offset of the
compact X-ray source (offset = 33.6 pc, from our HRI image) with respect
to the nucleus and extremely large intensity variations (from ASCA
observations). Previous evidence for a central black hole of mass
10^6.5^ M_sun_ comes from dynamical evidence (e.g., Bender, Kormendy, &
Dehnen 1996).

12. 1994CAG1..B...0000S
Re:NGC 0221
Local Group
Aug 19/20, 1950
103aE + Wr #25
90 min
M32, a companion to M31 (Sb; Hubble Atlas, p. 18; panel 149
here), has had an important historical role in understanding the
stellar content of E galaxies. As late as 1935, it was not known if
early-type galaxies were composed of stars or were structures with a
luminous central region surrounded by nonluminous particles which
scatter the central light (ten Bruggencate 1930). If the latter is the
case, polarization should occur. Polarization of the outer envelope
light was looked for by Sinclair Smith (1935) using the Mount Wilson
100-inch telescope, but was not found. For this and other reasons,
Smith favored the idea that E galaxies are composed of stars fainter
than the brightest stars resolved in later-type spiral galaxies, a
correct conjecture but not proved at the time.
The proof was achieved by Baade (1944a) upon his resolution of
M32 into stars with the Mount Wilson 100-inch Hooker reflector. The
resolution is well shown in the print here, made from a Palomar
200-inch plate. The individual stars are just beginning to resolve out
of the general background luminosity. A color-magnitude diagram of
these brightest stars is given by Freedman (1989).
The absolute magnitude of M32 is faint at M_T_ = -15.5, yet the
surface brightness is high, unlike in other dwarf E galaxies in this
luminosity range (Binggeli, Sandage, and Tarenghi 1984, Fig. 8). The
high surface brightness, among the highest known for any E galaxy
(Kormendy 1986), supports the view that M32 has been stripped of an
extensive outer envelope by the tidal action of M31. Following the
tidal stripping, the center of M32 became of even higher surface
brightness owing to partial collapse (dynamical cooling).
Morphologically, regardless of the process of formation, M32 is
the prototype of compact, low-luminosity cE galaxies of high surface
brightness, called class cE.

13. 1994CAG1..B...0000S
Re:NGC 0221
Local Group
Sep 3/4, 1921
Seed 30
multiple times
M32, a companion to M31 (Hubble Atlas, p. 18; panel 149 here), is
the prototype galaxy for the highly compact E galaxy form (cE
types). The effective surface brightness of galaxies of this type is
higher than normal at the relevant absolute magnitude (Sandage and
Perelmutter 1990, Fig. 11).
The print here contains five images made in a series of exposures
on the same plate taken by Hubble with the Mount Wilson 100-inch
Hooker Telescope.
The compactness of M32 extends to the central regions, as shown
by the nearly starlike fifth image in the print here.

14. 1976RC2...C...0000d
Re:NGC 0221
= Messier 032
= Arp 168
Pair with NGC 0224 in M 31 Group.
Description and Nucleus:
Bull. A.A.S., 3, 445, 1971.
P.A.S.P., 78, 495, 1966.
Ap. J. (Letters), 183, L73, 1973.
Photometry: (12 Color)
Ap. J., 145, 36, 1966.
Photometry: (5 Color)
A.J., 73, 313, 1968.
Photometry: (UBV)
Ap. J., 157, 55, 1969.
M.N.R.A.S., 162, 359, 1973.
Photometry: (10 Color)
Ap. J., 179, 731, 1973.
Photometry: (I.R. 2-10 microns)
Ap. J. (Letters), 175, L95, 1972.
M.N.R.A.S., 162, 359, 1973.
Spectrum and Systemic Velocity Dispersion:
IAU Symp. No. 15, 112, 1962.
Ap. J., 176, 91, 1972.
IAU Symp. No.58, 20, 1974.
Ap. J., 139, 532, 1964.
Ap. J., 141, 109, 1965.
Ap. J., 154, 212, 1968.
Ap. J., 164, 11, 1971.
Ap. J., 175, 649, 1972.
Mem. S. A. Ital., 43, 263, 1972.
Population Models:
Ap. J. Suppl., 22, No. 193, 1971.
Ap. J., 171, 463, 1972.
Astr. Ap., 20, 361, 1972.
Univ. of Texas Dissert., Austin, 1972.
Astrofizika, 4, 409, 1968.
Dynamics, Mass Determination and M/L:
Ap. J., 139, 284, 1964.
Ap. J., 176, 91, 1972.
Ap. J., 179, 423, 1973.
HII Regions and Planetary Nebulae:
Bull. A.A.S., 5, 13, 1973.
Ap. J. (Letters), 183, L73, 1973.
HI 21cm: (upper limit)
Observatory, 83, 245, 1963.
Astr. Ap., 29, 335, 1973.
M.N.R.A.S., 169, 607, 1974.
Radio Observations: (upper limit)
Astrophys. Lett., 11, 73, 1972.
Astrophys. Lett., 13, 65, 1973.
Astr. Ap., 34, 173, 1974.

15. 1975ByuO...47....1A
Re:ARK 012
(= NGC 0221)
Elliptical galaxy,
Red color.
One of the satellites of M31, Andromeda.

16. 1973UGC...C...0000N
Re:UGC 00452
Arp 168
E2 (de Vaucouleurs), E (Holmberg)
Companion to UGC 00454 = Messier 31 at 24, 1
`Faint diffuse plume curved away from M 31 disk' (Arp)
Main body 4 x 3
Sharp transition to a transparent envelope superimposed on M 31 disk, very
uncertain diameter

17. 1964RC1...C...0000d
Re:NGC 0221
= Messier 032
P(a?) with NGC 0224
In the M31 (Local) Group.
(B-V) constant, interperolated value.
Ap. J., 64, 325, 1926.
Ap. J., 71, 235, 1930.
(see also reference to NGC 0224).
Ap. J., 82, 192, 1935.
Ap. J., 100, 137, 1944.
Ap. J., 50, 384, 1919.
Ap. J., 71, 231, 1930.
Ap. J., 83, 424, 1936.
Ap. J., 108, 415, 1948.
Ap. J., 120, 439, 1954.
M.N.R.A.S., 96, 601, 1936.
Medd. Lund, II, 128, 1950.
Sov. A.J., 20, 54, 1943.
L'Astronomie, 76, 359, 1962.
Ap. J., 74, 36, 1931.
Ap. J., 83, 15, 1936.
Ap. J., 135, 732, 1962.
Ap. J., 136, 695, 1962.
A.J., 61, 97, 1956.
Bull. Abastumani, No. 18, 15, 1955.
Rotation and Mass:
Ap. J., 133, 393, 1961.
Ap. J., 133, 1092, 1961.
Ap. J., 134, 272, 1961.
Ap. J., 134, 910, 1961.
Ap. J., 136, 695, 1962.
A.J., 59, 273, 1954.
HI Emission:
Ap. J., 126, 471, 1957. (not confirmed).

18. 1918PLicO..13....9C
Re:NGC 0221
The well-known companion south of the nebula in Andromeda. Exceedingly
bright. In the long exposures it appears as a "burnt-out" oval 2.6' x 1.8',
with no trace of sphiral character in the outer portions. It lies in p.a.
150^deg^ +/-. The shortest exposures show a nucleus which is nebulous,
surrounded by bright nebular matter far brighter than the brightest parts of the
Nebula in Andromeda. The nucleus and inner nebular matter show strongly in 1m on

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