Measuring galaxy black hole masses

May 27, 2011
The galaxy NGC 4151 seen in a multi-color composite. The size of the massive black hole in its nucleus has been measured using a new infrared technique. Credit: X-ray (blue): NASA/CXC/CfA/J.Wang et al.; Optical (yellow): Isaac Newton Group of Telescopes, La Palma/Jacobus Kapteyn Telescope; Radio (red): NSF/NRAO/VLA

( -- Black holes, one of the most amazing and bizarre predictions of Einstein's theory of gravity, are irresistible sinks for matter and energy. They are so dense that not even light can escape from their gravitational clutches.

Massive black holes, containing millions to billions of of material, reside at the centers of most galaxies including our own Milky Way.

Although black holes are dark, their masses can be measured quite precisely from their on stars and other matter.

Astronomers have done just that over the past few decades by looking at the way gas around a nucleus moves under the influence of the .

The results on dozens of galaxies so far have shown that black hole sizes can be reliably estimated with this technique.

It is not always easy, however, to separate the light around the nuclear region from the rest of a galaxy's starlight in order to measure this moving gas.

SAO astronomers Martin Elvis and Margarita Karovska, together with five colleagues, have devised a new technique that takes advantage of the fact that the infrared of the gas also depends on its motion, and so also provides a measure of the black hole mass.

They find from a sample of fourteen previously measured galaxies that the infrared observations give very good agreement with other techniques.

Since infrared observations can in many situations be easier to obtain, the new technique will allow black hole measurements to be extended to many other galaxies.

Explore further: Computer Finds Massive Black Hole in Nearby Galaxy

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1.3 / 5 (14) May 27, 2011
Thanks for the news report on black holes (BH).

BH seemed reasonable before neutron repulsion was reported [1,2].

Now it seems more likely that our cyclic universe is controlled by competition between the attractive force of gravity and the repulsive force between neutrons [3].

1. "Attraction and repulsion of nucleons: Sources of stellar energy"
Journal of Fusion Energy 19, 93-98 (2001)

2. "Neutron Repulsion", The APEIRON Journal, in press, 19 pages (2011)

3."Is the Universe Expanding?", The Journal of Cosmology 13, 4187-4190 (2011)


With kind regards,
Oliver K. Manuel

5 / 5 (1) May 27, 2011
If there was a black hole made of dark matter, would you be able to measure it the same way?
5 / 5 (4) May 27, 2011
Only if there were 'dark neutron repulsion', right Ollie?

Don't be silly. There is no such thing as 'Dark Neutron Repulsion'.

It's 'Anti-Neutron Repulsion' and it is as real as the ingrown hair inside my nose.

1 / 5 (2) May 29, 2011
Gravitational worlds, they are moving or changing the orbit with their all family members depending on the nuclear of each other. Circumstantial evidence: cluster of galaxies and galaxy or stars, this there are the black holes in the deep of gravitational world, they are moving or changing the orbit with their all family members depending on the nuclear of each other. In this way; seeing, all of the family members combining by the gravitation power and finally super massive black holes depending on the nuclear fusion of the universe through that dark energy or black body.

not rated yet Jul 22, 2011
Now it seems more likely that our cyclic universe is controlled by competition between the attractive force of gravity and the repulsive force between neutrons [3].

To you and your crazy friend hilton of yours. Not even your students who worked with you on studying the nuclear rest masses you base your crazy theory off support your interpetation of the evidence. Get real oliver.

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