Code for Early Brighter Hotter
There is a code to follow when reading astronomy news stories. This recent story is an example.
'early' means it has an extreme red shift which is assumed to have an extreme velocity and so then it is also at an extreme distance. Billions of light years away means that many years ago.
These are incorrect assumptions. Red shifts from galaxies are different than from quasars. A galaxy red shift is proportional to the density of intergalactic hydrogen atoms in the light path so intervening clouds anywhere in the path increase the red shift. Quasar red shifts come from hydrogen ions zooming at a relativistic velocity toward the core and indicate nothing about the quasar distance or velocity.
In the 1930's galaxy red shifts were known to be proportional to distance. This was fine for those nearby galaxies having the same density of intergalactic hydrogen. Some galaxies can have a different ratio. This red shift should never be associated with velocity or time.
'brighter' means the red shift indicates an extreme (wrong) distance for this object but the (wrong) conclusion is the observed brightness is wrong; it must be brighter at that distance. This 'brighter' can refer to any part of the spectrum from radio to infrared to light to X-ray.
'hotter' depends on the telescope. With Chandra:
'hot' means there are X-rays. X-rays from intergalactic space are assumed to come from an extremely hot gas; while those from a galactic core are assumed from material around a black hole. Each is wrong because X-rays are part of synchrotron radiation indicating there are electric and magnetic fields in action (an electric current bending in a magnetic field). The assumption for 'hot' is a hot gas behaves like a blackbody so its high temperature results in blackbody radiation in the X-ray band.
For a black hole a proposed accretion disk is assumed to have that blackbody temperature for X-rays.
Black-body radiation is the thermal electromagnetic radiation within or surrounding a body in thermodynamic equilibrium with its environment, emitted by a black body (an idealized opaque, non-reflective body).
A hot gas or plasma is not a blackbody so its temperature cannot be measured this way. These assumed 'hot' temperatures are invalid.
The donut observed in M87 is a plasmoid, emitting synchrotron radiation; when the magnetic field in the torus intermittently collapses it ejects material along its axis, as observed.
With the Spitzer or WISE telescopes, 'hotter' is stronger in the infrared.
Images of the M87 core in radio or in infrared show the same donut, generated by the plasmoid and its synchrotron radiation. Technically this 'heat' is electrical not thermal.
From the news story about Spitzer:
like the radiation that roils off actively feeding black holes at the center of galaxies
The assumption is the observed infrared is from an accretion disk exhibiting a blackbody temperature. That is wrong.
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