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Post Info TOPIC: NGC 1277


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RE: NGC 1277
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NGC 1277 (also MCG 7-7-64, CGCG 540-104 and PGC 12434) is a magnitude +13.8 lenticular galaxy located approximately 220 million light years away in the constellation of Perseus. It is a member of the Perseus Cluster of galaxies. The galaxies NGC 1273, 1274, 1276, 1278, 1281 and PGC 12405 are located in the same celestial area.

On November 28, 2012, astronomers discovered a huge black hole in the galaxy; the second largest ever discovered. The galaxy has a black hole 4,000 times larger than the center of the Milky Way and whose mass is 17 billion times the mass of the Sun and makes up 14% of the mass of that galaxy.

In 2018 it was discovered by means of spectroscopic research that there is no more star formation in the galaxy. The galaxy consists only of old stars that were created more than 10 billion years ago.

The galaxy was discovered by the Irish astronomer Lawrence Parsons, 4th Earl of Rosse, using a 182.88 cm (72 inch) speculum reflector at Birr Castle on December 4, 1875.

Right ascension 03h 19m 51.5s, Declination +41° 34' 25"

NGC 1277 has been called a "relic of the early universe" due to its stars being formed during a 100 million year interval about 12 billion years ago.
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Hubble Finds Relic Galaxy Close to Home

The very rare and odd assemblage of stars has remained essentially unchanged for the past 10 billion years. This wayward stellar island provides valuable new insights into the origin and evolution of galaxies billions of years ago.

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Title: The over-massive black hole in NGC 1277: New constraints from molecular gas kinematics
Author: J. Scharwächter, F. Combes, P. Salomé, M. Sun, M. Krips

We report the detection of CO(1-0) emission from NGC 1277, a lenticular galaxy in the Perseus Cluster, which has been proposed to host a (1.3-1.7) x 1010 solar mass black hole (BH) based on stellar kinematic measurements. The CO(1-0) emission, observed with the IRAM Plateau de Bure Interferometer (PdBI) using both, a more extended (~1-arcsec resolution) and a more compact (~2.5-arcsec resolution) configuration, is likely to originate from the dust lane encompassing the galaxy nucleus at a distance of 0.9 arcsec (~320 pc). The spatially-unresolved double-horned CO(1-0) profile found at 2.5-arcsec resolution is likely to trace gas orbiting in the dust lane with rotational velocities of ~520 km s-1, indicative of an enclosed mass of ~2 x 1010 solar masses. Based on models with realistic mass distributions, the CO(1-0) kinematics is found to be consistent with a ~1.7 x 1010 solar mass BH, while a less massive BH is still possible assuming a large stellar mass-to-light ratio. The strongest CO(1-0) component, centred at ~+500 km s-1, is detected at 1-arcsec resolution. It shows an offset from the underlying continuum peak and may originate from a gas clump near the eastern orbital node of the dust lane. The extended 2.6-mm continuum emission is likely associated with a weak AGN, possibly characterized by an inverted radio-to-millimetre spectral energy distribution. Literature radio and X-ray data indicate that an ultra-massive BH in NGC 1277 would not only be over-massive with respect to the BH scaling relations, but also with respect to the fundamental plane of BH activity.

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Title: NGC1277: a massive compact relic galaxy in the nearby Universe
Author: Ignacio Trujillo, Anna Ferre-Mateu, Marc Balcells, Alexandre Vazdekis, Patricia Sanchez-Blazquez

As early as 10 Gyr ago, galaxies with more than 10^11 Msun in stars already existed. While most of these massive galaxies must have subsequently transformed through on-going star formation and mergers with other galaxies, a small fraction (<0.1%) may have survived untouched till today. Searches for such relic galaxies, useful windows to explore the early Universe, have been inconclusive to date: galaxies with masses and sizes like those observed at high redshift (M*>10^11 Msun; Re10 Gyr) with no evidence for more recent star formation episodes. The metallicity of their stars is super-solar ([Fe/H]=0.20+-0.04) and alpha enriched ([alpha/Fe]=0.4+-0.1). This suggests a very short formation time scale for the bulk of stars of this galaxy. This object also rotates very fast (Vrot~300 km/s) and has a large velocity dispersion (sigma>300 km/s). NGC1277 will allow future explorations in full detail of properties such as the structure, internal dynamics, metallicity, dust content and initial mass function at around 10-12 Gyr back in time when the first massive galaxies were built.

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Title: Is the black hole in NGC1277 really over-massive?
Authors: Eric Emsellem (ESO)

A claim has been made by van den Bosch et al. (2012) that NGC1277 hosts an over-massive BH with a mass larger than half its spheroid mass. We revisit this claim by examining the predictions from dynamical realisations based on new MGE models of NGC1277. We present realisations which fit the observed photometry. M/L is fixed following scaling relations which predict a Salpeter-like IMF. A model without a BH provides a surprisingly good fit of the observed kinematics outside the unresolved central region, but not, as expected, of the central dispersion and h4 values. A model with a MBH of 5 10^9 solar masses allows to fit the dispersion profile, consistently with models of the same mass and M/L in vdB+12. It departs from the central h4 values by only about twice the given uncertainty. A slightly varying M/L or the addition of high velocity stars would further lower the need for a very massive BH. These results do not rule out the presence of an over-massive BH at the centre of NGC1277. However, they lead us to advocate the use of 3-sigma confidence intervals for derived MBH as better, more conservative, guidelines for such studies. We caution for the use of ill-defined spheroidal components as an input for scaling relations, and emphasise the fact that a MBH in the range 2-5 10^9 solar masses would represent less than 5% of the spheroid mass of our models. This would make the BH in NGC1277 consistent or just twice as large as what a recent version of the MBH-sigma relation predicts. We examine the impact of the presence of a bar by running simulations from the same MGE model but with extreme anisotropies. An inner small bar forms, and an end-on view gets closer to fitting the central dispersion profile without the need for a central BH, while adding a black hole of 2.5 10^9 solar masses, in line with the prediction from scaling relations, allows to fit the dispersion peak and h3 profiles.

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Title: A Captured Runaway Black Hole in NGC 1277?
Authors: G. A. Shields, E. W. Bonning

Recent results indicate that the compact lenticular galaxy NGC 1277 in the Perseus Cluster contains a black hole of approximately 10 billion solar masses. This far exceeds the expected mass of the central black hole in a galaxy of the modest dimensions of NGC 1277. We suggest that this giant black hole was ejected from the nearby giant galaxy NGC 1275 and subsequently captured by NGC 1277. The ejection was the result of gravitational radiation recoil when two large black holes merged following the merger of two giant ellipticals that helped to form NGC 1275. The black hole wandered in the cluster core until it was captured in a close encounter with NGC 1277. The migration of black holes in clusters may be a common occurrence.

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Title: X-ray emission from the Ultramassive Black Hole candidate NGC1277: implications and speculation on its origin
Authors: A. C. Fabian, J. S. Sanders, M. Haehnelt, M. J. Rees, J. M. Miller

We study the X-ray emission from NGC1277, a galaxy in the core of the Perseus cluster, for which van den Bosch et al. have recently claimed the presence of an UltraMassive Black Hole (UMBH) of mass 1.7 times 10^10 solar masses, unless the IMF of the stars in the stellar bulge is extremely bottom heavy. The X-rays originate in a power-law component of luminosity 1.3 times 10^40 erg/s embedded in a 1 keV thermal minicorona which has a half-light radius of about 360 pc, typical of many early-type galaxies in rich clusters of galaxies. If Bondi accretion operated onto the UMBH from the minicorona with a radiative efficiency of 10 per cent, then the object would appear as a quasar with luminosity 10^46 erg/s, a factor of almost 10^6 times higher than observed. The accretion flow must be highly radiatively inefficient, similar to past results on M87 and NGC3115. The UMBH in NGC1277 is definitely not undergoing any significant growth at the present epoch. We note that there are 3 UMBH candidates in the Perseus cluster and that the inferred present mean mass density in UMBH could be 10^5 solar masses/Mpc³, which is 20 to 30 per cent of the estimated mean mass density of all black holes. We speculate on the implied growth of UMBH and their hosts, and discuss the possibility that extreme AGN feedback could make all UMBH host galaxies have low stellar masses at redshifts around 3. Only those which end up at the centres of groups and clusters later accrete large stellar envelopes and become Brightest Cluster Galaxies. NGC1277 and the other Perseus core UMBH, NGC1270, have not however been able to gather more stars or gas owing to their rapid orbital motion in the cluster core.

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Black hole upsets galaxy models

A group headed by Remco van den Bosch from the Max Planck Institute for Astronomy has discovered a black hole that shakes the foundations of current models of galaxy evolution. This monster has 17 billion solar masses and is thus significantly heavier than the models predict. And even more significantly: the object could be the most massive black hole known to date.
In order to determine the mass of the black hole, van den Bosch and his colleagues produced a dynamic model of the galaxy that includes all possible stellar orbits. Systematic comparisons of model and observation data then showed which orbits in combination with which mass value for the black hole provided the best explanation for the observations.
In the case of the NGC 1277 disk galaxy, the astronomers arrived at around 17 billion solar masses. This meant that the black hole could be the largest known object of this class. Researchers estimate the mass of the current record holder to be between 6 and 37 billion solar masses; if the true value is at the lower end, NGC 1277 breaks this record
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Giant black hole in tiny galaxy confounds astronomers

Astronomers have spotted an enormous black hole - the second most massive ever - but it resides in a tiny galaxy.
The galaxy NGC 1277, just a quarter the size of our own Milky Way, hosts a black hole 4,000 times larger than the one at the Milky Way's centre.
A report in Nature shows it has a mass some 17 billion times that of our Sun.

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Title: An Over-Massive Black Hole in the Compact Lenticular Galaxy NGC1277
Authors: Remco C. E. van den Bosch (1), Karl Gebhardt (2), Kayhan Gültekin (3), Glenn van de Ven (1), Arjen van der Wel (1), Jonelle L. Walsh (2) ((1) MPIA (2) UT (3) UMich)

All massive galaxies likely have supermassive black holes at their centers, and the masses of the black holes are known to correlate with properties of the host galaxy bulge component. Several explanations have been proposed for the existence of these locally-established empirical relationships; they include the non-causal, statistical process of galaxy-galaxy merging, direct feedback between the black hole and its host galaxy, or galaxy-galaxy merging and the subsequent violent relaxation and dissipation. The empirical scaling relations are thus important for distinguishing between various theoretical models of galaxy evolution, and they further form the basis for all black hole mass measurements at large distances. In particular, observations have shown that the mass of the black hole is typically 0.1% of the stellar bulge mass of the galaxy. The small galaxy NGC4486B currently has the largest published fraction of its mass in a black hole at 11%. Here we report observations of the stellar kinematics of NGC 1277, which is a compact, disky galaxy with a mass of 1.2 x 10^11 solar masses. From the data, we determine that the mass of the central black hole is 1.7 x 10^10 solar masses, or 59% its bulge mass. Five other compact galaxies have properties similar to NGC 1277 and therefore may also contain over-sized black holes. It is not yet known if these galaxies represent a tail of a distribution, or if disk-dominated galaxies fail to follow the normal black hole mass scaling relations.

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