Compact Elliptical Galaxy with Dark Matter
The NASA Chandra team just released on June 3 an image of a compact elliptical galaxy in both light and X-ray.
They claim the 'galaxy is brimming with dark matter.'
My interpretation of the image:
The visual image is an oval galaxy of the elliptical type with its brighter core similarly elongated.
The X-ray image shows the galaxy's core has an intense X-ray source at the center with weaker X-ray emissions coming from the surrounding area, in a non-symmetric shape. The release uses 'heart' for this shape.
From the story:
. To test this idea [dark matter] for the first time, a pair of astronomers studied the X-ray brightness and temperature of hot gas at different distances from Mrk 1216's center, so they could "weigh" how much dark matter exists in the middle of the galaxy.
"When we compared the Chandra data to our computer models, we found a much stronger concentration of dark matter was required than we find in other galaxies of similar total mass," said David Buote of the University of California at Irvine. "This tells us the history of Mrk 1216 is very different from the typical galaxy. Essentially all of its stars and dark matter was assembled long ago with little added in the past 10 billion years."
'Hot gas' means plasma. To measure its temperature like a gas one would be trying to measure the kinetic energy in the plasma as if its motion is caused by heat (though electric and magnetic fields are present to affect its motion). X-rays are being emitted from the core and beyond. When plasma moves as an electric current and bends in a magnetic field this results in synchrotron radiation; this can cover the spectrum from radio to X-ray.
This elliptical has a diffuse X-ray source indicating much plasma is in motion.
These 2 astronomers are looking for dark matter affecting a hot gas to cause a temperature capable of X-rays.
I am not surprised the Chandra data did not match their model. The assumptions are wrong so observations are interpreted wrong.
Using the scientific method, this model must be fixed because it does not follow observations. Instead dark matter is assumed to cause the observed deviation and the model continues until the next try. This is not good science.
This is the recent Chandra press release.
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