Astronomers Are Repeating a Blue Shift Mistake
The story claims a star cluster is zooming toward us as if catapulted out of the M87 galaxy, perhaps by its SMBH.
Unfortunately this story reveals the same blue shift mistake as with M31 and M33. No one fixed that mistake so it is easily repeated. Even Hubble saw the problem (100 years ago) but his solution was placing the Local Group on an island separate from the Hubble Flow. I posted about this isolation on May 4.
M31 is infamous because it is predicted to eventually collide with Milky Way. A number of galaxies in the direction of M31 have blue shifts. Most galaxies in the universe do not have a blue shift.
M31 relative velocity = −301 ± 1 km/s
M33 relative velocity = -179 ± 3 km/s
excerpt from a paper titled 'The M31 Velocity Vector. III. Future Milky Way-M31-M33 Orbital Evolution, Merging, and Fate of the Sun'
possible collision of M31 (and possibly M33) with the MW is the next major cosmic event affecting the environment of our Sun and solar system that can be predicted with some certainty.
this 'predict[ion] with some certainty' is disturbing because the prediction of future doom is a mistake and not justified.
NASA excerpt ===
Below is the spectrum of M31. The laboratory-measured lines of calcium K and H lines are indicated in red, and the laboratory wavelengths for them are given below. The corresponding calcium H and K lines from M31 can be seen in absorption.
Calcium K laboratory wavelength, Ca K = 3934 angstrom
Calcium H laboratory wavelength, Ca H = 3969 angstrom
NASA uses calcium absorption lines to determine the relative velocities of these two galaxies.
Absorption lines are from intervening atoms. For M31 and M33 these lines are blue shifted indicating these atoms are moving toward Earth.
These intervening atoms are not necessarily associated with the galaxies behind them. Both galaxies have similar velocities indicating the atoms are moving toward the Milky Way at the same velocity as observed for both galaxies.
The concluding these two galaxies are moving at the same velocity as these intervening atoms cannot be justified.
However astronomers believe M31-M33 pair is gravitationally bound due to their similar blue shift; this is part of that merger story.
Back to this runaway cluster from M87.
The attached news story has a link to its source titled ' Globular Cluster Toward M87 with a Radial Velocity < -1000 km/s: The First Hypervelocity Cluster'
paper excerpt ===
The Hectospec spectrum of HVGC-1 shows strong lines of Ca II H&K, moderate strength Balmer lines, and a weak G-band. There are no emission lines, other than night-sky line residuals.
In fact, the unusual velocity does not appear to be consistent with the tail of the GC velocity distribution of any individual Virgo galaxy, including M87. For M87 in particular the velocity dispersion at this projected radius is about 300 km/s, so HVGC-1 would be [an] outlier. We must look for other mechanisms to explain its relative velocity of over 2300 km/s with respect to M87.
They must most certainly look elsewhere because they are the wrong path right now by not dealing with a mistake.
Astronomers are using the same calcium absorption lines for this cluster as used for M31: 'Ca II H&K, no emission lines'
As with M31 the intervening calcium atoms are moving toward us but those atoms between M87 and us are moving faster.
The assumption these intervening calcium atoms are moving at the same rate as the cluster behind them cannot be justified.
The astronomers recognize these velocities are unbelievable and even call this unusual and an outlier but they believe the data interpretation anyway. Their paper resulted in a sensational news story. They had no paper if the bad conclusion were discarded.
Mistakes with absorption lines lie at the root of many wrong interpretations of the universe with the expanding fabric of space as a very notable example.
Hit back to go to previous page in history.
Here is the list of topics in this Cosmology Topic Group .
Ctrl + for zoom in; Ctrl - for zoom out ; Ctrl 0 for no zoom;
triple-tap for zoom to fit; pinch for zoom change; pinched for no zoom